Visual Basic for Android June11

Basic For Android Monday, 11 June 2012

Contents

1. B4A Cheatsheet ...................................................................................................... 4

Debug with a Toastmessage ............................................................................................. 4 Design resources and graphics ......................................................................................... 4 API Interfaces .................................................................................................................... 4 Dates ................................................................................................................................. 4 Getting Date from Sql database......................................................................................... 4 Read text file from External SD Card. ................................................................................ 4 Write text to a text file to SD Card. ..................................................................................... 4 How to open a webpage with WebView. ............................................................................ 4 Using Begin/End transaction - along with TransactionSuccessful greatly improves "writing" speed in SQL. .................................................................................................................... 4 "The application ... has stopped unexpectedly. Please try again." ..................................... 4 Adding menu items ............................................................................................................ 4 Use #Region ... #End Region. ........................................................................................... 5 Panel arrays ...................................................................................................................... 5 Ctrl + Space = auto complete ............................................................................................ 5 Tool tip information ............................................................................................................ 5 LogCat - logs ..................................................................................................................... 5 Open a PDF ...................................................................................................................... 5 Open an Excel file ............................................................................................................. 5 Running the Emulator through a proxy via the Command prompt ...................................... 5 Send data to Android calendar .......................................................................................... 6 Create a Glow, Blur, DropShadow effect on text ................................................................ 6 Built in buttons and images ................................................................................................ 6 Free database hosting ....................................................................................................... 6 Getting two lines in a listview ............................................................................................. 6 File Locations and working ................................................................................................ 6 Write / Read to files ........................................................................................................... 7

2. Project Download content using HTTP - dictionary ................................................. 8

HttpRequest ...................................................................................................................... 8 HttpResponse .................................................................................................................... 9

3. Project Metservice weather app ............................................................................ 10

Adding more cities to the weather app using Spinner. ..................................................... 13

4. Project The BikeFit calculator ................................................................................ 15

Create the Database ....................................................................................................... 15 SQL in the code ............................................................................................................... 17 Create the layout ............................................................................................................. 18 Activity Create code......................................................................................................... 21 Load the Database code.................................................................................................. 22 Listview Click Event ......................................................................................................... 23 Delete and Update - Database commands ...................................................................... 24 Add New Record to the Database ................................................................................... 24 Code for calculate............................................................................................................ 25 The Modules tab .............................................................................................................. 26 Easily find repeated code ................................................................................................ 26


The Results Activity ......................................................................................................... 27 The Results2 Activity ....................................................................................................... 28 The Results Layout using 2 panels .................................................................................. 29 The Help screen .............................................................................................................. 30

5. Project: Online Database Communication system................................................. 34

How to create an online Database ................................................................................... 34

Establish a connection string ........................................................................................... 36 Sending data to the database .......................................................................................... 37 Retrieving data from the database ................................................................................... 37 Uploading your PHP script ............................................................................................... 39

Android Communication Program Basic setup ................................................................. 40

Android Communication Program – Timestamp and Limit ............................................... 43

Using Timestamp ............................................................................................................ 43 Using Limit ...................................................................................................................... 44 Cutting out the unwanted text .......................................................................................... 44 Deleting data from your database. ................................................................................... 45

6. Project: GPS Program ........................................................................................... 49

Create the graphic Compass ........................................................................................... 49 Create the GPS ............................................................................................................... 50 GPS LocationChanged .................................................................................................... 52 Activity Pause and Resume code .................................................................................... 53 The Orientation_SensorChanged sub.............................................................................. 54 GPS on Google maps – using Intents .............................................................................. 55

7. Project: GPS and the net SQL: Record your position online ................................. 56

Create a new database table ........................................................................................... 56 Create a new PHP script ................................................................................................. 57 Getting satellites .............................................................................................................. 59 Retrieving data from the database and displaying distance to saved GPS location ......... 60

8. Project: Getting an address from a Geolocation using XML .................................. 63

Geolocation ..................................................................................................................... 66 XML parser ...................................................................................................................... 66

9. Getting an error in your hc_ResponseSuccess? Fix the taskID. ........................... 67

10. Project: Creating a Weather Widget ...................................................................... 68

The Service Module......................................................................................................... 69 Designing the Temperature Widget ................................................................................. 76

11. Project: Alarm scheduler sends email to contacts ................................................. 79

Date and Time ................................................................................................................. 80 Write to a file ................................................................................................................... 82 Read from a file to a list ................................................................................................... 82 Sending an SMS ............................................................................................................. 83

12. Project: Text to Speech Program........................................................................... 85

Text to speech – stripped for other programs .................................................................. 87

13. Project: Capture all SMS messages entering your phone ..................................... 88

Logs and Toastmessageshow are crucial to debugging .................................................. 88 Working with Service and Activity Modules ...................................................................... 89


Saving and Reading to files ............................................................................................. 89 The Activity (main) code .................................................................................................. 89 Code for the Service Activity(sms) ................................................................................... 94 The Activity(smstest) ....................................................................................................... 97 Designing the Widget ...................................................................................................... 98

14. Project: Voice Recognition program ...................................................................... 99

15. Project: Voice recognition in SMS messages program. ....................................... 101

Create a transparent layout – a floating button .............................................................. 101 The Voice Recognition Activity Module .......................................................................... 103

16. Maps – Hashmap for Java, Hashtables for .net ................................................... 107

17. Use Map to save multiple data to a single file ..................................................... 108

18. Project: Recipe selector using JSON................................................................... 109

JSON Overview ............................................................................................................. 109 Recipe Program construction ........................................................................................ 111 How to make a hyperlink that opens the web browser ................................................... 114


1. B4A Cheatsheet Debug with a Toastmessage

Toastmessage is a timed popup useful to

show you what’s happening in your code.

ToastMessageShow("message

here",false) ' true=3sec , false=2

sec

Design resources and graphics

http://developer.android.com

http://www.androidpatterns.com/

http://jgilfelt.github.com/android-actionbar

Nine patch images nine-patch-images-tutorial

API Interfaces

http://www.programmableweb.com/

http://cloudmade.com/

Dates

Dates values are stored as the number of

milliseconds since 1 January, 1970. This value

is too large for an Int. It must be saved in a

Long variable.

Dim now As Long

now = DateTime.Now

Getting Date from Sql database

The date from my SQL database comes in as

yyyy/MM/dd

Here is a simple way to display in the required

format.

Dim TheDate As Long

DateTime.DateFormat = "yyyy-MM-dd"

TheDate=

DateTime.DateParse(Cursor1.GetString(

"Dob"))

DateTime.DateFormat = "dd/MM/yyyy"

Text= DateTime.Date(TheDate)

Read text file from External SD Card.

Folder SDCARD/Android/data/ your app

name

Dim savedtext As String

savedtext =

File.ReadString(File.DirDefaultExtern

al, "mytextfile.txt")

Write text to a text file to SD Card.

File saved to SDCARD/Android/data/ your

com file name

File.WriteString(File.DirDefaultExter

nal, "mytextfile.txt", "text to

write")

How to open a webpage with WebView.

1. add Webview to designer.

2. add button to designer.

3. generate members.

Button1_Click

Dim UserURL As String

UserURL = "http://www.google.com.au/"

WebView1.LoadUrl(UserURL)

End Sub

Using Begin/End transaction - along with

TransactionSuccessful greatly improves

"writing" speed in SQL.

My code went from 12 seconds to

milliseconds in writing records.

SQL1.BeginTransaction

Try

'block of statements like:

For i = 1 to 1000

SQL1.ExecNonQuery("INSERT INTO table1

VALUES(...)

Next

SQL1.TransactionSuccessful

Catch

Log(LastException.Message) 'no

changes will be made

End Try

SQL1.EndTransaction

"The application ... has stopped

unexpectedly. Please try again."

Some errors are not caught by Basic4android

and then you see this message. To find the

cause of the error you should check the

unfiltered logs in the Logs tab (right pane).

The filtered logs will usually not show any

message about this error.

Adding menu items

Adding menu items to activity is done by

calling Activity.AddMenuItem or

AddMenuItem2.

http://developer.android.com/design/index.html

http://www.androidpatterns.com/

http://jgilfelt.github.com/android-actionbarstylegenerator

http://www.basic4ppc.com/forum/basic4android-getting-started-tutorials/14283-nine-patch-images-tutorial.html#post80908


http://cloudmade.com/

http://www.basic4ppc.com/android/help/views.html#activity_addmenuitem


Usually you will want to call it in Sub

Activity_Create.

Use #Region ... #End Region.

to create custom collapsible sections in your

code. Very handy for hiding a large blocks of

source code

#Region My collection of functions

Sub SomeThing()

End Sub

Sub Another()

End Sub

#End Region

Panel arrays

Dim panels(8) As Panel

Defines 8 Panels.

panels.Length = number of items, number of

Panels.

The Panel items go from

panels(0), panels(1), panels(2), panels(3),

panels(4), panels(5), panels(6),

panels(7) 8 items with indexes from 0 to 7 so

panels.Length - 1 .

So Dim panels(8) As Panel

For i = 0 To panels.Length – 1

is correct and necessary

Ctrl + Space = auto complete

Pressing Ctrl + Space activates the auto

complete feature which will then show you a

list with the available keywords, variables,

modules, methods, subs, properties and fields.

The list includes a description for most items.

Pressing Ctrl + Space after typing the first few

letters will usually select the required item

automatically.

Tool tip information

While writing methods parameters, a tool tip

will be opened with the method signature and

description.

The tool tip might hide some important code

that you now need.

LogCat - logs

The LogCat tab displays the device built-in

logs. These logs are very useful for debugging.

You can log messages with the Log keyword.

In order to start displaying the logs you press

on the Connect button.

Log(whatever you want)

Open a PDF

Sub OpenPDF(FileName As String)

Dim i As Intent 'Requires a reference to the Phone library

i.Initialize(i.ACTION_VIEW, FileName)

i.SetType("application/pdf")

i.WrapAsIntentChooser("Choose PDF Viewer")

StartActivity(i)

End Sub

Open an Excel file

Sub OpenExcel(FileName As String) Dim i As Intent 'Requires a reference to the Phone library i.Initialize(i.ACTION_VIEW, FileName) i.SetType("application/vnd.ms-excel") i.WrapAsIntentChooser("Choose Excel Viewer") StartActivity(i) End Sub

Running the Emulator through a proxy via

the Command prompt

c:\Android\android-sdk\tools>emulator.exe -avd test -http-proxy http://Username:[email protected]:3128

This c:\Android\android-sdk\tools> has to be

done first then attach the rest. Test = avd

name, IP address:port 10.6.0.254:3128


Send data to Android calendar

Sub Activity_Create(FirstTime As Boolean) Dim Intent1 As Intent Intent1.Initialize(Intent1.ACTION_MAIN,"com.androi d.calendar") Intent1.SetComponent("com.android.calendar/.LaunchActivity") StartActivity(Intent1) End Sub

Create a Glow, Blur, DropShadow effect on

text

Dim Obj1 As Reflector

Obj1.Target = Label1

args(0) = 3 'Radius of the

Blur/GlowDropShadow

types(0) = "java.lang.float"

args(1) = 3


args(2) = 3


args(3) = Colors.ARGB(255,0,0,255)

' Color of th Glow/Blur

types(3) = "java.lang.int"

Obj1.RunMethod4("setShadowLayer",

args, types)

Built in buttons and images

Go to

http://developer.android.com/reference/androi

d/R.drawable.html images

http://androiddrawables.com/ put the number

in code below

Dim bd As BitmapDrawable

bd = p.GetResourceDrawable(17301555)

Msgbox2("Message", "OK",

"","",bd.Bitmap)

Free database hosting

http://www.000webhost.com/

Getting two lines in a listview

Sub Globals

Type ListViewData (FirstRow As

String, SecondRow As String)

End Sub

For i = 0 to 100

Dim lvd As ListViewData

lvd.Initialize

lvd.FirstRow = "abc"

lvd.SecondRow= "def"

ListView1.AddTwoLines2(lvd.FirstRow,

lvd.SecondRow, lvd)

Next

Sub ListView1_ItemClick(Position As

Int, Value As Object)

Dim lvd As ListViewData

lvd = Value

...

End Sub

File Locations and working

There are several important locations where

you can read or write files.

File.DirAssets

The assets folder includes the files that were

added with the file manager. These files are

read-only. You cannot create new files in

this folder (which is actually located inside

the apk file).

File.DirInternal / File.DirInternalCache

These two folders are stored in the main

memory and are private to your application.

Other applications cannot access these

files.The cache folder may get deleted by the

OS if it needs more space.

File.DirRootExternal

The storage card root folder.

File.DirDefaultExternal

The default folder for your application in the

SD card. It will be created if required. The

folder is: <storage

card>/Android/data/<package>/files/

File.WriteString - Writes the given text to a

new file.

File.ReadString - Reads a file and returns it

content as a string.

File.WriteList - Writes all values stored in a

list to a file. All values are converted to string

type if required. Each value will be stored in

its own line. Note that if a value contains the

new line character it will saved over more than

one line and when you read it, it will be read

as multiple items.

File.ReadList - Reads a file and stores each

line as an item in a list.

File.WriteMap - Takes a map object which

http://developer.android.com/reference/android/R.drawable.html

http://developer.android.com/reference/android/R.drawable.html

http://androiddrawables.com/

http://www.000webhost.com/


holds pairs of key and value elements and

stores it in a text file. The file format is not too

important unless the file is supposed to be

edited manually. This format makes it easy to

edit it manually. One common usage of

File.WriteMap is to save a map of "settings" to

a file.

File.ReadMap - Reads a properties file and

returns its key/value pairs as a Map object.

Note that the order of entries returned might be

different than the original order.

Write / Read to files

'write it to a file

File.WriteString(File.DirInternalCache, "nettalk.txt",result)

'get it back from the file

reader.Initialize(File.OpenInput(File.DirInternalCache, "nettalk.txt"))

Dim name As String

name = reader.ReadLine


2. Project Download content using HTTP - dictionary The basic steps in getting content from the net to your phone are quite simple.

In this project we are going to access the online dictionary at

http://dictionary.reference.com/ enter a term and get the results.

First add the Http library. Here is the basic documentation on it

http://www.basic4ppc.com/android/help/http.html

Create a layout with an Edittext box named WordBox and a button named SearchButton.

HttpRequest

Holds the target URL and other data sent to the web server. The initial time out is to 30000

milliseconds (30 seconds).

Sub Process_Globals

Dim hc As HttpClient

Dim req As HttpRequest

End Sub

Sub Globals

'define the views on the layout, a text box and a button

Dim WordBox As EditText

Dim SearchButton As Button

End Sub

Sub Activity_Create(FirstTime As Boolean)

'load the layout

Activity.LoadLayout("Main")

hc.Initialize("hc")

End Sub

'#### Controls ####

Sub SearchButton_Click

req.InitializeGet("http://dictionary.reference.com/browse/" & WordBox.Text)

hc.Execute(req, 1)

End Sub

http://dictionary.reference.com/

http://www.basic4ppc.com/android/help/http.html


HttpResponse

An object that holds the response returned from the server. The object is passed in the

ResponseSuccess event. You can choose to read the response synchronously or

asynchronously. It is important to release this object when it is not used anymore by calling

Release.

'#### Routines ####

Sub hc_ResponseSuccess(Response As HttpResponse, TaskId As Int)

Dim SearchWord As String

SearchWord = Response.GetString("UTF8") 'Get the whole page

'The line below finds <div class="pbk"><span class="pg">

SearchWord = SearchWord.Replace(QUOTE, "'") 'Replace double quotes with single quotes for easy handling.

SearchWord = SearchWord.SubString(SearchWord.IndexOf("<div class='pbk'><span class='pg'>") + 34) 'Add 34 so we grab the definition after the tag (there are 34 characters in the above string when you count to the right) You can add 34 to the 0 substring start below instead

SearchWord = SearchWord.SubString2(0, SearchWord.IndexOf("</span>")) 'Grab only the definition enclosed

Msgbox(WordBox.Text & " is a " & SearchWord, "") 'Voila!!

End Sub

Sub hc_ResponseError(Response As HttpResponse, Reason As String, StatusCode As Int, TaskId As Int)

If Response <> Null Then

Msgbox("Error: " & Response.GetString("UTF8"), "Connection Error")

Response.Release

End If

End Sub


3. Project Metservice weather app Similar to the above exercise this exercise downloads the current temperature from the

metservice and extracts the temp from it.

The heart of it is cutting out the temperature from the code.

Improve this code by:

1. Allowing people to change the city to another one.

2. We will make it into a widget so it stays on the front of the phone

later.

Sub Process_Globals

Dim hc As HttpClient 'download the page

Dim hcimage As HttpClient 'download the image


Dim reqimage As HttpRequest

End Sub

Sub Globals

Dim temp As String

Dim btnweather As Button

Dim edtweather As EditText

Dim lbltemperature As Label

Dim img As Bitmap

‘Set a default start city when there is nothing in the DB

Dim selectedcity As String :selectedcity ="Christchurch"

Dim townpath As String

Dim label1 As Label ‘holds the temp

Dim imgtemp As ImageView

Dim pic As String 'holds the image

End Sub


Activity.LoadLayout("main")

hc.Initialize("hc")

hcimage.Initialize("hcimage")

End Sub

Sub btnweather_click

strplace = "christchurch" 'note its lower case

townpath = "http://m.metservice.com/towns/"& strplace

'Log(townpath)

req.InitializeGet(townpath)


hc.Execute(req, 1)

End Sub


Dim temp As String

temp = Response.GetString("UTF8") 'Get the whole page

'Cut beginning and end to get the code for the temp itself

temp = temp.SubString(temp.IndexOf("<div class=" & QUOTE & "summary" & QUOTE & ">")) 'cut to first occurance off

temp = temp.SubString2(21, temp.IndexOf("</ul></div></div>")) ' find last occurance

temp = temp.Replace(QUOTE,"'") ' replace double with single quotes

edtweather.Text = temp 'show the downloaded code so you can work on it.

Dim temperature As String 'pull the temperature from the code

temperature = temp

temperature = temperature.SubString(temperature.IndexOf("ul'><h2>"))

temperature = temperature.SubString2(8, temperature.IndexOf("<span "))

lbltemperature.Text = temperature

pic = temp 'pull the pic from the code

pic = pic.SubString(pic.IndexOf("wx-icons/")) 'start position

pic = pic.SubString2(9, pic.IndexOf("' width")) ' 6 is the number from counting the letters above

pic = pic.Trim

'looking for the image, is it already in the cache?

If File.Exists(File.DirInternalCache, pic) Then

'if so then load it

imgtemp.Bitmap = LoadBitmap(File.DirInternalCache, pic)

Log("image in cache")

Else 'otherwise go and get it from the net

Getimage ‘ run the get image sub

End If

Dim strtime As String 'pull the time from the code

strtime = temp

Dim timecolon As String

timecolon = strtime.IndexOf(":") 'find the colon between the time eg 11:23am

strtime = strtime.SubString2(timecolon -2, timecolon +5) 'take 2 off the colon and add 5 on to get the whole time 11:23am

label1.Text = strtime

End Sub


Sub getimage 'this gets the image from the net

Dim imagepath As String

imagepath = "http://m.metservice.com/sites/all/themes/mobile/images/wx-icons/"& pic

reqimage.InitializeGet(imagepath)

hcimage.Execute(reqimage, 1)

End Sub

Sub hcimage_ResponseSuccess(Response As HttpResponse, TaskId As Int)

‘If you successfully get the image then run this code its sitting in the cache so get it out

Response.GetAsynchronously("ImageResponse", _

File.OpenOutput(File.DirInternalCache, pic, False), True, TaskId)

End Sub

‘when the image has stopped downloading (useful for big images)

Sub ImageResponse_StreamFinish (Success As Boolean, TaskId As Int)

If Success = False Then

Msgbox(LastException.Message, "Error")

Return

End If

‘load it into the image bitmap

imgtemp.Bitmap = LoadBitmap(File.DirInternalCache, pic)

End Sub

‘typical error reporting when the image was unable to be downloaded

Sub hcimage_ResponseError(Response As HttpResponse, Reason As String, StatusCode As Int, TaskId As Int)


Msgbox("Error: " & Response.GetString("UTF8")& "Cannot find ", "Connection Error")

Response.Release

ProgressDialogHide

ToastMessageShow("Image not loading",True)

End If

End Sub

‘typical error reporting when the temp was unable to be downloaded




Response.Release

ProgressDialogHide

ToastMessageShow("bugger",True)


End If

End Sub

Adding more cities to the weather app using Spinner.

Create a Spinner, Dim SPcity As Spinner and a variable to hold the city Dim

selectedcity As String in Globals.

Create a sub to add the cities to the spinner

Sub addCity

'add more cities

SPcity.Add("Christchurch")

SPcity.Add("Auckland")

SPcity.Add("Wellington")

SPcity.Add("Dunedin")

SPcity.Add("Hamilton")

End Sub

At the end of Sub Activity_Create add the following code to load the spinner with the

cities Give it a default value SPcity.SelectedIndex = 1 so it loads a city at startup. AddCity

will load the cities above to the spinner.

addCity

SPcity.SelectedIndex = 1

Activity.Title="Mothership for weather app for " & selectedcity

This is the click event on the spinner, passing the value of what you clicked on to the

selectedcity variable. It also turns on a button to save the city to a text file.

Sub SPcity_ItemClick (Position As Int, Value As Object)

'pass the value you have selected to the variable

selectedcity = Value

btnsavecity.Enabled = True

End Sub

Change the Sub btnweather_click button click event so that it loads the spinner value. Note

that it has to be lower case for the url to work.

strplace = selectedcity.ToLowerCase 'note its lower case


If you want to save it so that it will open at that city later, and when you create a widget then

you need to save it to a text file. That is really easy.

Sub btnsavecity_click


'save the city you has selected to a text file

File.WriteString(File.DirInternal, "WeatherCity.txt",selectedcity)

End Sub

Change the btnweather_click code to open the file that has been saved.

The first time you run it there is no file to draw from. So If File.Exists checks that the file is

there. If not it just uses the value that was given in the Dim selectedcity As String

:selectedcity ="Christchurch"

Sub btnweather_click

If File.Exists(File.DirInternal, "WeatherCity.txt") Then

selectedcity = File.ReadString(File.DirInternal, "WeatherCity.txt")

End If

strplace = selectedcity 'note its lower case


'Log(townpath)


hc.Execute(req, 1)

End Sub


4. Project The BikeFit calculator

Create the Database

Go to Firefox/Tools/ Addons. Add in the SQLite manager

After you have installed SQLite manager in to Firefox open a new database and call it

Bikefit.

Create a new table using right click Create table from the Tables(0)

Click on ADD

Add the following fields. Also call the table bikefit (or any name you want).

Read about SQLlite datatypes here http://www.sqlite.org/datatype3.html

http://www.sqlite.org/datatype3.html


Save the file to the Files folder of your program, or move it there later.

Create some data to use as an example

Close out from your program and rename the file itself from bikefit.sqlite to bikefit.sql. (I

don’t know why, considering that Android uses sqlite files and not sql, but it must be a bug

somewhere in the SQL Library ), and make sure its saved in your files folder.


SQL in the code

We are going to use the SQL library so need to load it in. There are two

types in this library.

An SQL object gives you access to the database. The Cursor object

allows you to process queries results.

Usually you will want to declare the SQL object as a process global

object. This way it will be kept alive when the activity is recreated. SQLite

stores the database in a single file. When we initialize the SQL object we

pass the path to a database file (which can be created if needed).

First we define our database variables.

Sub Process_Globals

Dim SQL1 As SQL

Dim cursor1 As Cursor

Now we need to start coding for it. In the Activity Sub, which runs when the program first

begins, we need to copy the database from the Assets folder to the Internals folder as files

can’t be written to in the Assets folder.

Files distributed as part of an app cannot be written to in the default location. To move the

file(s) to a storage area which allows writing to the file, add the file to the app in

Activity_Create add the following code:


If File.Exists(File.DirInternal,"bikefit.sql") = False Then

File.Copy(File.DirAssets,"bikefit.sql",File.DirInternal,"bikefit.sql")

End If

If SQL1.IsInitialized = False Then

SQL1.Initialize(File.DirInternal, "bikefit.sql", False)

End If


Create the layout

There are a number of ways to create your layout. The most ‘obvious’ is to make a panel

and attach the objects to it.

Create the panel pnlbg first, The other objects will be stuck to the panel and can be

manipulated with the panel later. At this stage size is not an issue as it can be set

programmatically.

Labels just holding text don’t need to be explicitly named as they won’t be in the code.

Open the Designer and the Abstract Designer and click on the Status to connect it to the

emulator

Then you can see the design in the emulator and adjust it from there as well as using the

Abstract designer to find the names of the Views. If you are lucky enough to have your

phone plugged in you can see the layout on the phone and move it around by hand as well.


In the Designer you can see the Views and their properties. Firstly set the pnlbg panel with

the values in the properties. Each of the Views you add to your layout then attaches to this

panel.


Once you have made your layout you need to generate the

members. This mostly a shortcut way to declare the variables

that you are going to use.

Go Tools, in the Designer window and then click Generate

Members

This will create the Dims in Sub Globals

Sub Globals

'These global variables will be redeclared each time the activity is created.

'These variables can only be accessed from this module.

Dim edtarm As EditText

Dim edtseam As EditText

Dim edtshoulder As EditText

Dim edtsternum As EditText ' height

Dim panelbg As Panel

Dim btncalculate As Button 'run

Dim btndelete As Button 'delete

Dim btnsave As Button ' change

Dim btnnew As Button 'save new

Dim bmp As Bitmap ‘ you need to add this for later

Dim btnarm As Button

Dim btnseam As Button

Dim btnshoulder As Button

Dim btnsternum As Button

Dim LVdb As ListView


Activity Create code

After you have created your layout it needs to be added to the Sub

Activity_Create(FirstTime As Boolean) so that its loaded when the program runs.

You can replace “Main” with the name of whatever your layout is.

Activity.LoadLayout("Main")

We can also add the rest of the code that needs to run when the program is first created.

At the beginning of an object's life, the Java virtual machine (JVM) allocates enough

memory on the heap to accommodate the object's instance variables. When that memory is

first allocated, however, the data it contains is unpredictable.

If the memory were used as is, the behaviour of the object would also be unpredictable. To

guard against such a scenario, Java makes certain that memory is initialized, at least

to predictable default values, before it is used by any code.

Initialization is important because, historically, uninitialized data has been a common source

of bugs. The Java language, has built-in mechanisms that help you ensure proper

initialization of the memory occupied by a newly-created object. With proper use of these

mechanisms, you can prevent an object of your design from ever being created with an

invalid initial state.

Earlier we defined a bitmap image (Dim bmp As Bitmap). And now we have to initialise it

bmp.Initialize(File.DirAssets, "android48.png")

For our Edittext boxes we can specify what type of keyboard will be used. In this case we

only want numbers to be added to the boxes.

edtarm.InputType = edtarm.INPUT_TYPE_NUMBERS

Finally we want a title to appear at the top of the layout.

Activity.Title="Bike Fit: Sizing calculator"

All the code added to Activity_Create.

bmp.Initialize(File.DirAssets, "android48.png")

'uses only the numeric keyboard

edtarm.InputType = edtarm.INPUT_TYPE_NUMBERS

edtseam.InputType = edtseam.INPUT_TYPE_NUMBERS

edtshoulder.InputType = edtshoulder.INPUT_TYPE_NUMBERS

edtsternum.InputType = edtsternum.INPUT_TYPE_NUMBERS

Activity.Title="Bike Fit: Sizing calculator"


Load the Database code

Now that we have the Views loaded into the layout we can start to write the code that loads

the database into the Listview. The ListView control is a very powerful control. It allows you

to show short or long lists in a very "sleek" way. Read more about it here.

First we get the data from the database and pass it to “Cursor1” which we defined earlier.

Cursor is just the name of the object that holds the data from the database, it might also be

thought of as a datatable.

Pass the data to cursor1

cursor1 = SQL1.ExecQuery("SELECT * FROM bikefit")

Then we make a For next loop, starting at 0 and ending with the rowcount – 1 (because we

started at 0 instead of 1)

For i = 0 To cursor1.RowCount – 1

Then we just get the data we want and pass it as a long line of data, to the

Listview.AddSingleLine

LVdb.AddSingleLine(cursor1.GetString("ID")& " : " &cursor1.GetString("Name")& " " & cursor1.GetLong("Sternum")& " " & cursor1.GetLong("Inseam")& " " & cursor1.GetLong("Arm")& " " & cursor1.GetLong("Shoulder"))

We then set the details for that line and finish with the next

LVdb.SingleLineLayout.ItemHeight = 40 etc

All code.

Sub DBload

LVdb.Clear'need to clear the list

cursor1 = SQL1.ExecQuery("SELECT * FROM bikefit")

For i = 0 To cursor1.RowCount - 1

cursor1.Position = i

LVdb.AddSingleLine(cursor1.GetString("ID")& " : " &cursor1.GetString("Name")& " " & cursor1.GetLong("Sternum")& " " & cursor1.GetLong("Inseam")& " " & cursor1.GetLong("Arm")& " " & cursor1.GetLong("Shoulder"))

LVdb.SingleLineLayout.ItemHeight = 40

LVdb.SingleLineLayout.Label.TextSize = 20

LVdb.SingleLineLayout.label.TextColor = Colors.Black

LVdb.SingleLineLayout.label.Color = Colors.White

Next

End Sub

Finally add DBload to the VERY END of Sub Activity_Create So that it runs at

startup.

http://www.basic4ppc.com/forum/basic4android-getting-started-tutorials/6537-listview-tutorial.html


Listview Click Event

When we click on an item in the listview we want those numbers to be passed to the edittext

boxes in the layout. This is a Short Click event, there is also a Long Click event

Value is the data of the line that is being clicked. Value As Object It is passed to the idvalue.

idvalue = Value

We want to get the place of the first : and pass that number to countit. Then using Substring

we get the ID number by starting at 0 and going to the countit number.

countIt = idvalue.IndexOf(":") 'find location of separator

idvalue = idvalue.SubString2(0,countIt) 'find first part of label text

Now we have the ID of the row we can put it back into the database to pull out the values

again and pass them to the edittext boxes. We also could carry on using the code above to

find the next : and then getting the number from there as well.

Sub lvdb_ItemClick (Position As Int, Value As Object)' click on the entry in the list

Dim idvalue As String

idvalue = Value

countIt = idvalue.IndexOf(":") 'find location of sperator

idvalue = idvalue.SubString2(0,countIt) 'find first part of label text

ID = idvalue

cursor1 = SQL1.ExecQuery("SELECT * FROM bikefit where ID = '" & ID & "' ")



edtarm.text=cursor1.getString("Arm")

edtseam.text=cursor1.getString("Inseam")

edtshoulder.text=cursor1.getString("Shoulder")

edtsternum.text=cursor1.getString("Sternum")

Next

End Sub


Delete and Update - Database commands

Clicking on the listview row selected the ID for that row, as seen above, then when you have

that number you can easily delete the row or save it back to the database if you changed it.

Sub btndelete_click

SQL1.ExecNonQuery("DELETE FROM bikefit where ID = '" &ID & "' ")

DBload

End Sub

Saving the row by taking the text from the edittext boxes.

Sub btnsave_click

SQL1.ExecNonQuery("UPDATE bikefit set Sternum ='"& edtsternum.text &"', Inseam ='"& edtseam.text &"', Arm ='"& edtarm.text &"' , Shoulder = '"& edtshoulder.text &"' WHERE ID = " & ID)

DBload

End Sub

Add New Record to the Database

Adding a new record uses the Dialogs library to enter the name. This

means someone else did all the hard work for you.

This library contains several modal, that is blocking, dialogs by which the user can enter

data. Presently they are an InputDialog for text, a TimeDialog for times, a DateDialog for

dates, both a ColorDialog and a ColorPickerDialog for colors, a NumberDialog for

numbers,a FileDialog for folders and file names and a CustomDialog.

Sub btnnew_click ' save new

Dim dialog As InputDialog

dialog.Input = ""

dialog.HintColor = Colors.ARGB(196, 255, 140, 0)

Dim ret As Int

ret = DialogResponse.CANCEL

ret = dialog.Show("Enter Your name", "Bike Fit", "Save", "Exit", "", bmp)

Dim strname As String ' name of person

strname = dialog.Input

If strname = "" OR edtarm.text = "" OR edtseam.text = "" OR edtshoulder.text = "" OR edtsternum.text ="" Then

Msgbox("You have to enter all fields","Missed data field")

Else

'Grab the last ID number which is the highest number

cursor1 = SQL1.ExecQuery("SELECT ID FROM bikefit ")

If cursor1.RowCount > 0 Then


http://www.basic4ppc.com/android/help/dialogs.html



Dim NewID As Int

NewID = cursor1.GetInt("ID")

Next

End If

NewID = NewID +1 ' add 1 to the ID number to make a new ID field

SQL1.ExecNonQuery("INSERT INTO bikefit VALUES('" & NewID & "','" & strname & "','" & edtsternum.text & "','" & edtseam.text & "','"& edtarm.text &"', '" & edtshoulder.text & "')")

DBload

End If

End Sub

Code for calculate

Under the Sub Process_Globals define the following variables. They are defined here

because they will be used in other activities, Results, and Results2

Dim helpselect As Int

Dim lngsternum As Long

Dim lnginseam As Long

Dim lngarm As Long

Dim lngshoulder As Long

Dim ID As Int ' ID of each entry

The click event for the Run Button. Pass the data from the text boxes to the variables.

This loads the next activity called results that we make next.

StartActivity("results")

Sub btncalculate_click

lngsternum = edtsternum.Text

lnginseam = edtseam.Text

lngarm = edtarm.Text

lngshoulder = edtshoulder.Text


End Sub


The Modules tab

The modules tab on the right is really handy to use. The top section

shows you the activities in your project, while the bottom shows each

sub in your activity.. Just click on the Sub to go to that part of the code.

Easily find repeated code

If you are looking for all the places where a piece of your code, be it a

variable or view etc is repeated in your activity just double click on it to

select it. Then down the right you will see light blue lines. Scroll down to

the lines with the scrollbar and each duplicate entry will show up. It’s a

really good tool.


The Results Activity

In order to show the results of the bikefit, the 4

fields from the Main layout page, we will create 2

Activities to hold the code. This might be overkill, I imagine we could have the code for the

results all on one activity, but this is to show how you can share a layout between Activities.

So we will have two activities, Results and Results2, they will both

Create a new activity and call it results

There are no process Globals as all the results are kept in this activity. You might want to

create the layout first and then generate these views using the generate tool.

Sub Globals

Dim lblhandlebar As Label

Dim Lblreach As Label

Dim btnback As Button

Dim btnnext As Button

Dim pnlHelp As Panel

Dim pnlhelp2 As Panel

End Sub

The Result and Results2 Activities uses one layout named “results” which has two panels

on it. pnlHelp and pnlHelp2. PnlHelp.Visible is set to True to show it for the results activity

while the second panel is set to .visible = False to hide it.

In the next Activity Results2, the panel visibility is reversed.


Activity.LoadLayout("results")

pnlHelp.Visible = True

pnlhelp2.Visible = False

pnlHelp.Top=0

pnlHelp.Left=0

pnlHelp.Height=Activity.Height

pnlHelp.Width=Activity.Width

Activity.Title="Bike Fit: Handlebar and Reach"

result

End Sub

The sub that calculates the results and passes it to the label

Sub result

lblhandlebar.text = (Main.lngshoulder * 0.875)&"cm" 'handlebar

Lblreach.text = ((((Main.lngsternum - Main.lnginseam) + Main.lngarm) / 2) + 4) &"cm"

End Sub


Sub btnnext_click

StartActivity("results2")

End Sub

Sub btnback_click

Activity.Finish

End Sub

The Results2 Activity

Sub Globals

Dim lblframe As Label

Dim lblsaddle As Label

Dim pnlHelp As Panel


Dim btnback2 As Button

Dim btnnext2 As Button

End Sub


Activity.LoadLayout("results")

pnlHelp.Visible = False

pnlhelp2.Visible = True

pnlhelp2.Top=0

pnlhelp2.Left=0

pnlhelp2.Height=Activity.Height

pnlhelp2.Width=Activity.Width

Activity.Title="Bike Fit: Frame and Saddle"

result

End Sub

Sub result

lblframe.text = (Main.lnginseam * 0.67)&"cm" 'frame

lblsaddle.text = (Main.lnginseam * 0.883)&"cm" 'saddle

End Sub

Sub btnnext2_click



btnback2_click

End Sub

Sub btnback2_click

Activity.Finish

End Sub

The Results Layout using 2 panels

This layout uses two panels, and the Views for each Activity are stuck on their panel. Then

the panels are either made visible or invisible.

Here are the Views to be added to each panel. This is taken directly from the Sub Globals

Create the panel first then make sure you stick the views on them.

Results Activity Results2 Activity Dim pnlHelp As Panel

Dim lblhandlebar As Label Dim Lblreach As Label Dim btnback As Button Dim btnnext As Button


Dim lblframe As Label Dim lblsaddle As Label Dim btnback2 As Button Dim btnnext2 As Button


The Help screen

One layout with changing data depending on the case statement in the Activity.

In the Main Activity need to make a variable to hold the help number that will be accessed

later from the Help Activity. Therefore it needs to be declared in the Process Globals sub of

the Main Activity.

Sub Process_Globals

Dim helpselect As Int

In the Main activity add the code to activate each of the help buttons. We could use the

Sender property to get the value of the helpselect, which is smaller, however its nice to be

lazy sometimes.

Sub btnarm_click

helpselect = 1

StartActivity("help")

End Sub

Sub btnseam_click

helpselect = 3


End Sub

Sub btnshoulder_click

helpselect = 4



End Sub

Sub btnsternum_click

helpselect = 5


End Sub

Create a new Activity and call it Help.

In the designer create a new layout called Help and layout the fields something like this.

Generate your Views into the Help Activity you made earlier, it should look something like

below. It’s pretty obvious.

Sub Globals

Dim imgbox As ImageView

Dim lblhelp As Label

Dim lbltitle As Label

Dim panel1 As Panel

Dim btnclose As Button

Dim imgarm As Bitmap

Dim imgheight As Bitmap

Dim imgsternum As Bitmap

Dim imgshoulder As Bitmap

Dim imginseam As Bitmap

Dim lblcalc As Label

End Sub


In Sub Activity_Create we need to create the select statement that will load which of the 4

help information clicked on by the button.


Activity.LoadLayout("help")

Select Main.helpselect

Case 1 'arm

lbltitle.Text ="Measure your arm length"

lblhelp.text = "Measure from your shoulder to your knuckles. "

imgarm.Initialize(File.DirAssets,"arm.jpg")

imgbox.Bitmap = imgarm

lblcalc.Text ="This helps give your reach. (((sternum - inseam) + arm) / 2) + 4)"

Activity.Title="Bike Fit: Arm measuring"

Case 2 'height

lbltitle.Text ="Measure your height"

lblhelp.text = "In your socks or bare feet, stand with your heels and buttocks against the wall Measure from the ground to the top of your head"

imgheight.Initialize(File.DirAssets,"height.jpg")

imgbox.Bitmap = imgheight

lblcalc.Text ="???"

Case 3 'seam

lbltitle.Text ="Measure your inner leg"

lblhelp.text = "Wear your cycling shorts, and take the measurements in bare feet. Place a book OR other solid Object up against the top of your inner leg pelvic bone AND measure from the top of that To the Floor."

imginseam.Initialize(File.DirAssets,"inseam.jpg")

imgbox.Bitmap = imginseam

lblcalc.Text ="Frame size = inseam * 0.67, Saddle height = inseam * 0.883"

Activity.Title="Bike Fit: Inseam measuring"

Case 4 'shoulder

lbltitle.Text ="Measure your shoulder width"

lblhelp.text = "Measure your shoulder width by the outside of the bony protrusions at the top of your shoulders"

imgshoulder.Initialize(File.DirAssets,"shoulder.jpg")

imgbox.Bitmap = imgshoulder

lblcalc.Text ="Handle Bar width = shoulder * 0.875"

Activity.Title="Bike Fit: Shoulder measuring"

Case 5 'sternum

lbltitle.Text ="Measure from your sternum to the floor"


lblhelp.text = "In your socks or bare feet, stand with your heels and buttocks against the wall. Measure from the ground to the sternum notch at the top of your ribcage / bottom of your neck."

imgsternum.Initialize(File.DirAssets,"sternum.jpg")

imgbox.Bitmap = imgsternum

lblcalc.Text ="Used to calcualte Reach and Frame height, Saddle height"

Activity.Title="Bike Fit: Sternum measuring"

End Select

End Sub

Sub btnclose_click

'StartActivity("Main")

Activity.Finish

End Sub


5. Project: Online Database Communication system This program connects to an internet server and allows the user to send and receive data,

particularly text in this case. This requires 3 parts, the Android program, a PHP interface,

and a web based database in SQL.

Android PHP script Database

First thing we need is a web based database to hold our data.

How to create an online Database The steps below are not specific just to this website, but to any webhost using the Cpanel,

MySql and PHPAdmin programs which is a very high proportion of them.

1. Go here and create an account and WRITE YOUR DETAILS DOWN

2. Once you are logged in go to your

account and click on Go to CPanel

3. Scroll down to MySQL and click on it

4. Create a new Database using your names and pws

5. Keep a record of the details you get, you

will need them soon.

$mysql_host = "mysql8.000webhost.com";

$mysql_database = "a5858161_test";

$mysql_user = "a5858161_gary";

$mysql_password = "PW";

6. Go back to CPanel and click on PHP

MyAdmin

7. Click to enter your database


8. Create a new table for your database. It

doesn’t matter how many fields, you can

add them easily when needed later (as we

will)

9. Create the following fields

10. Once created click on Insert

11. Add some sample data to your database to have something to work with

Under Browse you can see the added data

12. Go back to Insert and add some more rows set

“Insert another new row” so that you stay in the same window

You should now have a simple database with some data

Creating a PHP script to provide access to your database.


Android cannot directly access the internet based database so needs to go through a script.

This can be written in a number of languages such as PHP or ASP, we will use PHP as its

easy and very popular.

PHP can be written in many programming systems, even as simple as notepad. I use

Komodo Edit from http://www.activestate.com/komodo-edit however you might have another

program.

There are two ways to create your PHP page, one is to act to let Android pass directly

through and do whatever it wants to the database. This leaves the database open to

hacking and attacks, as any device can access the PHP script when you know the path so

its not a secure option.

The other way is to put your SQL code in the PHP page in functions and control what the

program does by controlling the function allowed to run. So you can stop people deleting

data by not having a delete function in the PHP code, or restricting it.

This is by far the best option. This is the code below, its quite easy to follow when you get it.

PHP starts and ends with <?php to ?> . Everything between these tags is seen as PHP

code.

Establish a connection string

This passes your DB details to 3 connection variables (created with a $ in front) which are

then passed to the connection string to gain access to the database. These 3 variables

could be named anything it’s the mysql_connect(Server, Username, Password) that is

the key here.

When you have a connection to the database you need to select the table in that database

you want. mysql_select_db("Table")

$mysqlDatabaseName = "mysql8.000webhost.com";

$mysqlUsername = "a5858161_gary";

$mysqlPassword = "PW";

mysql_connect($mysqlDatabaseName, $mysqlUsername, $mysqlPassword) or die(mysql_error());

mysql_select_db("a5858161_test") or die(mysql_error());

Once this works then you can pass whatever SQL statements you want to the database and

get replies.

http://www.activestate.com/komodo-edit


Sending data to the database

In this case we send the data from the phone to the PHP of.

"http://android-dsed.host22.com/netdb.php?action=add&name=me&deviceID=deviceID&text=inputtext

The code in the PHP scans the url we send and extracts from it the values we want to pass

to the database, name, device and text.

Action is used to tell the PHP which function we are to run, Add or Getall. We can create

any number of functions and run them this way.

So here we run the Action function and get the name, device, text from the string passing it

to the variables $name, $deviceID, $text.

if($action == "add"){

$name = $_GET['name'];

$deviceID = $_GET['deviceID'];

$text = $_GET['text'];

Then we run an SQL query and pass those three variables into the database.

mysql_query("INSERT INTO webDB

(name, deviceid, text) VALUES('$name', '$deviceID', '$text') ") or die(mysql_error());

The or die(mysql_error()) is just to give an escape in case the query doesn’t work, like Try

/ Catch.

Retrieving data from the database

When retrieving data from the database we just use a straight SQL statement again.

$result = mysql_query("SELECT name, text, deviceID FROM webDB") or die(mysql_error());

Data is formatted by line when it returns with "\r\n" being a line break. The string is

concatenated with a . (as opposed to a & or + that we are used to).

while($row = mysql_fetch_array($result)){

echo $row['name'];

echo "\r\n".$row['text'];

echo "\r\n".$row['deviceID']."\r\n";

This will return from the DB

In the Android code we use reader.readline to return the following in

the same order as left.

Me name = reader.ReadLine

Message linetext = reader.ReadLine

DeviceID postdeviceID = reader.ReadLine


Here is the full PHP code, save it as netdb.php or any other name you can remember.

<?php

$mysqlDatabaseName = "mysql8.000webhost.com";

$mysqlUsername = "a5858161_gary";

$mysqlPassword = "PW";

mysql_connect($mysqlDatabaseName, $mysqlUsername, $mysqlPassword) or die(mysql_error());

mysql_select_db("a5858161_test") or die(mysql_error());

if(isset($_GET['action'])){

$action = $_GET['action'];

}

if($action == "add"){

$name = $_GET['name'];


$text = $_GET['text'];

mysql_query("INSERT INTO webDB

(name, deviceid, text) VALUES('$name', '$deviceID', '$text') ")

or die(mysql_error());

}

if($action == "getall"){

$result = mysql_query("SELECT name, text, deviceID FROM webDB" ) or die(mysql_error());

//DATA OUT TO PROGRAM


echo $row['name'];



}

}

?>


Uploading your PHP script

Now we have a php script acting as a gateway to the database we need to upload it on to

the server. That’s easy.

Go to File Manager in your CPanel

Go to the Public_html folder in your account.

Then upload your file to that folder.

Done!

Check your php is working by typing in the path to the DB as well as the Getall action.

Your path will have another name, instead of android-dsed below. This should return the

sample data you have in your database.

http://android-dsed.host22.com/netdb.php?action=getall

It won’t look much, just raw data on your screen something like this although I have more

data in my Database.


Android Communication Program Basic setup The coding for this program is remarkably easy. At this stage its just

a simple system but has a myriad of potential uses. Think of this as a

bare bones system to be further developed to meet the needs.

The code is commented. Replace the Android-DSED in

req.InitializeGet("http://android-dsed.host22.com/netdb.php?&action=getall")

with the path to your own path

Test that the path is correct by putting your path http://android-

dsed.host22.com/netdb.php?&action=getall in the browser If its

OK it will return the data from your database in the browser itself.

The android code below is commented to make it easy to follow.

Basically you make a connection using HTTpClient, (Dim httpC As

HttpClient ) then make a request using HTTpRequest (Dim Req As

HttpRequest).

This returns an HttpResponse which is either successful Sub

httpC_ResponseSuccess or not Sub httpC_ResponseError.

All the rest is window dressing to make it work.

When you add your text you can’t have any spaces between the words as they break the

URL that being sent. So …

inputtext = inputtext.Replace(" ", "_")

… is added to the code to replace the spaces with an underscore

When the text is returned to the phone we want to get rid of those underlines again to make

it look nice. So use

'strip out the underscores

result = result.Replace("_"," ")

As a result it looks like ordinary text leaves the phone and ordinary text is shown back on

the phone.

Sub Process_Globals

Dim httpC As HttpClient 'the Connection client

End Sub

Sub Globals

Dim pnlbg As Panel ' background panel


Dim btnsubmit As Button ' Send to DB

Dim btncallDB As Button ' Retrieve from DB

Dim txtinput As EditText ' Text entry field

Dim lvoutput As ListView ' Show the messages from the DB

Dim reader As TextReader ' reading the text from the DB

Dim phoneInfo As PhoneId

Dim deviceID As String

deviceID = phoneInfo.GetDeviceId ' getting the Phone ID

End Sub



httpC.Initialize("httpC")

'keeps it transparent when you scroll to see the text

lvoutput.ScrollingBackgroundColor = Colors.Transparent

End Sub

‘Nothing here for these two subs

Sub Activity_Resume

End Sub

Sub Activity_Pause (UserClosed As Boolean)

End Sub

‘click event getting data from the DB

Sub btncallDB_Click

Dim req As HttpRequest ' requesting net data

req.InitializeGet("http://android-dsed.host22.com/netdb.php?&action=getall") ‘create the connection string

httpC.Execute(req, 1) ‘ send the request

ProgressDialogShow("Fetching all data...") ‘make a progress dialog that give the viewer something to look at

End Sub

Sub httpC_ResponseSuccess (Response As HttpResponse, TaskId As Int)

lvoutput.Clear ‘ clear the list box so it loads the new data in fresh

Dim result As String 'download results

result = Response.GetString("UTF8")



'write it to a file





'read it line by line to a string called line,

Dim name As String

name = reader.ReadLine this loads the username "me" echo $row['name'];

Dim i As Int :i = 0'dimension a counter just to show in the scrollview

Do While name <> Null 'run a loop while there is a line

i = i+1

'returns the message text echo "\r\n".$row['text'];

Dim linetext As String

linetext = reader.ReadLine

'returns the DeviceID text echo "\r\n".$row['text'];

Dim postdeviceID As String

postdeviceID = reader.ReadLine

'Set up the listview formatting and adds name and then text

lvoutput.SingleLineLayout.Label.TextSize = 16

lvoutput.SingleLineLayout.ItemHeight = 35

lvoutput.SingleLineLayout.Label.TextColor = Colors.Black

lvoutput.AddSingleLine(i&" "& name & " "& linetext)

name = reader.ReadLine 'passes only to the ME text

Loop

reader.Close

ProgressDialogHide ‘stop the progress dialog box

lvoutput.SetSelection(0)

End Sub

Sub lvoutput_ItemClick(Position As Int, Value As Object)

Msgbox(Value, "Message") 'click on the message shows it in a msgbox

End Sub

Sub httpC_ResponseError (Response As HttpResponse, Reason As String, StatusCode As Int, TaskId As Int)

Msgbox("Error connecting to score server"&CRLF&CRLF&Reason,"Error ("&StatusCode&")")

ProgressDialogHide

End Sub


'SUBMIT MESSAGE

Sub btnsubmit_click

Activity.Title = "Submitted"

Dim inputtext As String

inputtext = txtinput.Text

If inputtext <>"" Then 'if there is something in the textbox

inputtext = inputtext.Replace(" ", "_")

ProgressDialogShow("Submitting data...")

Dim req As HttpRequest 'create a DB request

sendrequest = "http://android-dsed.host22.com/netdb.php?action=add&name=me&deviceID="

req.InitializeGet(sendrequest & deviceID &"&text=" & inputtext)

httpC.Execute(req, 1)

Else 'if empty show an error message

ToastMessageShow("Put a message in first", False)

End If

txtinput.Text = "" 'clear the text box

End Sub

Android Communication Program – Timestamp and Limit So you got it to work, and it looks OK, however there are some major flaws.

1. How do you know when a message was sent?

2. How do you limit how many messages are returned? Every time you click Read All

the entire database is sent to you which will quickly become a pain in the neck.

3. How do we get the listview to show the data with the most recent entry at the top?

Using Timestamp

To solve the first one we could send a time with your message which gets stored on the net,

however the problem with this is that if someone else is in another part of the world that

timestamp will be different to yours.

Lets make a timestamp that is on the server so that all messages are tagged with the same

timezone.

Go back to PhpAdmin, and open your database and find the Add New Field area, it appears

in a number of windows.


Create a new field called Timestamp

The TIMESTAMP data type is used for values that contain both date and time parts.

TIMESTAMP has a range of '1970-01-01 00:00:01' UTC to '2038-01-19 03:14:07' UTC.

If the column is auto-updated, it is automatically updated to the current timestamp when the

value of any other data in the row is changed from its current value.

We can use the Timestamp as an index field as well if we want and we can perform time

calculations from it to get all the posts in the last 24 hours for example.

Using Limit

We can limit how many records are returned with the Limit command. In your PHP getall

code set the limit to 10 (LIMIT 10 ), or whatever number you wish.

Using our new Timestamp order the records by Timestamp and in reverse order (ORDER

BY TIMESTAMP DESC)


$result = mysql_query("SELECT name, text, deviceID FROM scoreTable ORDER BY TIMESTAMP DESC LIMIT 10 " ) or die(mysql_error());

Save and upload your new PHP script to the server.

Cutting out the unwanted text

Notice that when you return the data to the phone it comes back with

two unwanted lines of code at lines 7 and 8 in the image.

We can easily remove this using indexof and substring commands

from our earlier exercise. Go ahead and make the changes.


Deleting data from your database.

This is easy in theory but takes more work than you think.

First make a new button on your layout and call it Btndelete.

Declare the following under Sub Globals

Dim btndelete As Button

Dim message As String ‘ holds the message string

Firstly we need to get a field to identify the row of data. The

best field for this, being the easiest, is the ID field.

In your PHP we need to call down the ID field as well so we

can use it int eh delete query. In the code below I have

added ID, and echo $row['ID']; to get the ID field into your

program.


$result = mysql_query("SELECT ID, name, text, deviceID FROM webDB ORDER BY TIMESTAMP DESC LIMIT 10" ) or die(mysql_error());



echo $row['ID'];

echo "\r\n".$row['name'];



}

}

Now that it is being returned. We need to put it into the program.

Since we now have an ID field lets rebuild the following sub using ID as the main control.

As well we can do some housework.

'strip out the end text with the annoying text at the end

Dim Endstring As Int

Endstring = result.IndexOf("<!")

result = result.SubString2(0, Endstring)

Full code.


lvoutput.Clear

'download results

Dim result As String



'strip out the end text with the annoying text at the end

Dim Endstring As Int

Endstring = result.IndexOf("<!")

result = result.SubString2(0, Endstring)



'write it to a file




'Starts the download Get back the ID echo $row['ID'];

Dim ID As String

ID = reader.ReadLine

'run a loop while there is a still an ID - it gets the next ID at the end of the loop

Do While ID <> Null

'read it line by line to a string called line this loads the user name "name" echo $row['name'];

Dim name As String

name = reader.ReadLine


Dim linetext As String

linetext = reader.ReadLine


Dim postdeviceID As String

postdeviceID = reader.ReadLine

'adds name and then text otherwise will be on seperate lines

lvoutput.SingleLineLayout.Label.TextSize = 16

lvoutput.SingleLineLayout.ItemHeight = 35

lvoutput.SingleLineLayout.Label.TextColor = Colors.Black

lvoutput.AddSingleLine(ID &": "& name & " "& linetext & " " & postdeviceID)

ID = reader.ReadLine

Loop

reader.Close

ProgressDialogHide

lvoutput.SetSelection(0)

End Sub


We now have the Device ID of the phone showing as well. If

you are just using the Emulator it comes up blank (no phone).

Later we can use the device ID to make the Me only show for

your phone.

Once we can see the data on your screen we need to find a

way to delete out the fields we want.

As we have a touch device the easiest way is to touch the

entry you don’t want.

The Listview Itemclick is the event that a touch on the text raises so this will be changed

adding message = Value to the variable so that message holds the string that is raised

when you click on it. We have to declare it under Globals as well Dim message As String

Sub lvoutput_ItemClick(Position As Int, Value As Object)

message = Value

Msgbox(Value, "Message") 'click on the message shows it in a msgbox

End Sub

Finally we need to add the code under the Delete Button. First it looks in the message for

the : eg in .

We want what is left of the : to get the ID number (4 or 5).

IndexOf returns the number of where the : is stripstring = IDdelete.IndexOf(":")

This number is then put into IDdelete = IDdelete.SubString2(0, stripstring) which has the

following Substring2(startnumber, endnumber) So it starts at 0 and ends at the number of

the : Of course the end number will vary depending on how many numbers in the ID eg: 4,

or 32, or 45342345.


Sub btndelete_click

Dim IDdelete As String

IDdelete = message

'need to strip the message back to the first ID, by using the indexof

Dim stripstring As Int

stripstring = IDdelete.IndexOf(":")

IDdelete = IDdelete.SubString2(0, stripstring)

'this shows me in the code if I have it right

Log(IDdelete)


req.InitializeGet("http://android-dsed.host22.com/netdb.php?&action=delete&ID="&IDdelete)


ProgressDialogShow("deleting message...")

End Sub

In the webDB.php add the following code, anywhere outside of the other functions.

First it looks for the action delete. When it finds that it pulls out the ID which is then passed

to $deleteID and run in the SQL.

//delete messages

if($action == "delete"){

$deleteID = $_GET['ID'];

mysql_query("DELETE FROM webDB WHERE ID = '$deleteID'" ) or die(mysql_error());

}


6. Project: GPS Program Creating a GPS system involves two parts, the first is getting the GPS subsystems to work

on the phone, this is pretty easy. The second part is

getting the rotating arrow in the compass to work. This is

also easy but requires accepting some design voodoo is

going on.

Start with a new project

Set your Orientation to portrait, otherwise it will change

all the time when you wave your phone around.

Create the graphic Compass

Create an imageview named IVcompass

Set it with the values for dimensions

shown in the image. They will be seen in

the code with

Dim x, y, h, w As Int

Use the Add Images to add in the

compass and the arrow and then add the

compass (the circular background

image) to the Image

File. Save the layout as Main.


The difficulty with the compass is that the background image is static but the Arrow itself

rotates depending on the GPS bearings.

It’s getting that rotation of the Arrow that is the issue, we need to create a zone for the

Arrow to rotate with the rectangle object and using canvas.

Sub Process_Globals

'create a bitmap to hold the compass and the arrow

Dim imgcompass, imgArrow As Bitmap

Dim Rect1 As Rect

End Sub

Sub Globals

Dim IVcompass As ImageView 'the compass background

Dim Canvas1 As Canvas

Dim Bitmap1 As Bitmap

End Sub


Dim x, y, h, w As Int

Activity.LoadLayout("main.bal")

'set the compass and arrow

imgArrow.Initialize(File.DirAssets, "arrow.png")

imgcompass.Initialize(File.DirAssets, "compass.png")

Canvas1.Initialize(IVcompass)

w=IVcompass.Width

h=IVcompass.Height

Bitmap1.Initialize3(Canvas1.Bitmap)

Rect1.Initialize(0,0,w,h)

Canvas1.DrawBitmap(imgArrow, Null, Rect1)

End Sub

This should give a centred arrow on the Compass background.

Create the GPS

Import and activate the GPS and Phone Libraries.

There are three relevant objects.

The main one is GPS. The GPS manages the connection and events.

The second is Location.

A Location is a structure that holds the data available regarding a specific "fix". The data

includes the latitude and longitude coordinates, the time (expressed as ticks) of this fix

and other information like bearing, altitude etc


The Location also includes other functionalities like calculating the distance and bearing

to another location and methods to convert the coordinate’s string formats.

Usually you will work with Location objects passed to you in the LocationChanged events.

However you can also initialize such objects yourself (this is useful for calculating distance

and bearing between locations).

The last one is GPSSatellite. This is a structure that holds information regarding the

currently known satellites. It is passed to you in GPSStatus event.

We are also going to create a location to save out GPS to called Dim SETloc As Location

and another using the Compass Dim Compass As PhoneSensors to show the direction

North Dim NPloc As Location

Lets create a new GPS and some storage places to record locations. Dim SETloc As

Location and Dim NPloc As Location so we can always find North again. To keep track of

the current location Dim Currentloc As Location. The locations are generated in the

LocationChanged sub later on.

Sub Process_Globals

'Create the GPS

Dim GPS1 As GPS

Dim SETloc As Location 'SET LOCATION

Dim NPloc As Location 'NORTH POLE

Dim Currentloc As Location 'CURRRENT LOC FROM THE GPS

Dim Compass As PhoneSensors

Dim GPSbearing, Compassbearing As Float

Dim Latitude, Longitude, lastlat, lastlon As Double

Under Activity Create lets initialise the GPS

If FirstTime Then

'North pole

NPloc.Initialize2("90:00:00", "00:00:00") 'North Pole

SETloc.Initialize()

SETloc = NPloc 'first time pass NP to Setloc to point north

Compass.Initialize(Compass.TYPE_ORIENTATION)

GPS1.Initialize("GPS")

Currentloc.Initialize() ‘create a location to hold current location

End If


GPS LocationChanged

The main part of the GPS is the LocationChanged sub.

Sub GPS_LocationChanged (Loc As Location)

This gives us the Location object named here loc. The heart of

the GPS

Loc can be broken down to all sorts of

properties such as Latitude and

Longitude.

We will need to pass these values back to

the screen so make 3 labels

Dim lblaccalt As Label

Dim lbllonlat As Label

Dim lblspeed As Label

As loc is stuck inside of that sub if you want to use it anywhere

else in the program you need to pass it to another Location

variable. In this case we pass it to Currentloc. This holds all of the

properties of the Loc

Currentloc = Loc

You can pass the Lat and Lon in 2 ways Decimal values or Hours,

minutes etc. You need decimal to pass to google maps, but people

like to see minutes on the screens for their GPS systems. This

'textlon = Loc.Longitude gives decimal and textlat =

Loc.ConvertToMinutes(Loc.Latitude) gives minutes, you choose

for what you need.

'textlon = Loc.Longitude

'textlat = Loc.Latitude

textlat = Loc.ConvertToMinutes(Loc.Latitude)

textlon = Loc.ConvertToMinutes(Loc.Longitude)

All code

Sub GPS_LocationChanged (Loc As Location)

'This Is the main event. Loc holds the data for the new fix.

Longitude = Loc.Longitude


Latitude = Loc.Latitude ' Store the new latitude position in this string

Currentloc = Loc ' make a new location called Current LOC give it current data

Dim degrees As Float

'bearing is the direction

If GPSbearing <> Loc.BearingTo(SETloc) Then ' change the compass to point to the setLOC

GPSbearing = Loc.BearingTo(SETloc)

degrees = (GPSbearing - Compassbearing)

Canvas1.DrawBitmap(Bitmap1, Null, Rect1)

Canvas1.DrawBitmapRotated(imgArrow, Null, Rect1, degrees)

Activity.Invalidate()

End If

'work out speed

Dim locspeed As Double

locspeed = Loc.Speed * 3.6 '= kmh

lblspeed.Text = "Speed = " & Round2(locspeed ,2) &" KPH"

Dim textalt, textacc As Double

Dim textlat, textlon As String

'textlon = Loc.Longitude

'textlat = Loc.Latitude

textlat = Loc.ConvertToMinutes(Loc.Latitude)

textlon = Loc.ConvertToMinutes(Loc.Longitude)

textalt = Loc.Altitude

textacc = Loc.Accuracy

lbllonlat.Text =" Lat - " & textlat & CRLF & " Lon - " & textlon

lblaccalt.Text ="Altitude - " & Round2(textalt, 0) & " Meters" & CRLF & "Accuracy - " & Round2(textacc, 0) & " Meters"

End Sub

Activity Pause and Resume code

The GPS turns off when you leave the activity, this is to save the battery. When you restart

the program, or reenter this activity it is turned on again. Obviously there might be times

when you don’t want it turned off.


'turn off the GPS to save the battery

GPS1.Stop

End Sub


Sub Activity_Resume

'start listening for GPS - turn it on

If GPS1.GPSEnabled = False Then 'turn on your GPS

ToastMessageShow("Please enable the GPS device", True)

'Will open the relevant settings screen.

StartActivity(GPS1.LocationSettingsIntent)

Else

'Listen to GPS with no filters.

'The Start method receives two values which are the minimum time (milliseconds) AND the minimum distance (meters) between events. An event will be raised when at least one of these criterions are met. This can help saving battery. In our case we are passing 0 AND therefore will get all fix events.

GPS1.Start(0,0)

End If

Compass.StartListening("Orientation")

End Sub

The Orientation_SensorChanged sub

Orientation_SensorChanged is used to expose the changes in the GPS to the arrow on the

compass. The code is trying to limit the compass reading to +/- 360 in quarter degrees units

by using an integer value for x where x Is the value of the compass bearing * 4, rather than

using the raw GPS values and so smoothing it out and saving on battery and CPU.

The If statement, If Compassbearing <> x/4.0 Then checks if the stored value for the

bearing has changed (that Is, has the bearing changed by more than a ¼ degree); If so, it

updates the stored value and moves the arrow.

Sub Orientation_SensorChanged(Values() As Float)

Dim degrees As Float, x As Int

x = ((2880 + Values(0) * 4) Mod 2880) - 1440

If Compassbearing <> x/4.0 Then

Compassbearing = x/4.0

degrees = GPSbearing - Compassbearing

Canvas1.DrawBitmap(Bitmap1, Null, Rect1)

Canvas1.DrawBitmapRotated(imgArrow, Null, Rect1, degrees)

Activity.Invalidate()

End If

End Sub


GPS on Google maps – using Intents

We are going to add the Google map link as a menu item. You can easily use a button but

menus are good to develop

Add the following to Sub Activity_Create

Activity.AddMenuItem("Google Map Location", "Googlemap")

Then at the bottom of the code have a click event for that menu item. Sub Googlemap_click

Intent objects are messages which you can send to the OS in order to do some external

action in the phone. We want to open the Google maps on the cell phone.

Firstly you have define a new intent, Dim Intent1 As Intent

Then initialise it with the options you want Initialize (Action As String, Uri As String)

Intent1.Initialize(Intent1.ACTION_VIEW,URI)

Gets or sets the Intent action. Other actions are ….

ACTION_APPWIDGET_UPDATE As String

ACTION_CALL As String

ACTION_EDIT As String

ACTION_MAIN As String

ACTION_PICK As String

ACTION_SEND As String

ACTION_VIEW As String

Then we need a SetComponent (Component As String). Explicitly sets the component that

will handle this intent.

Intent1.SetComponent("googlemaps")

The Intent object should finally be started with StartActivity keyword StartActivity(Intent1)

Sub Googlemap_click

Dim Intent1 As Intent

URI= "geo:" & Latitude & "," & Longitude & "?q=" & Latitude & "," & Longitude



StartActivity(Intent1)

'streetview works as well

' URI= "google.streetview:cbll=" & Latitude & "," & Longitude & "&cbp=1"

'google.streetview:cbll= Latitude, Longitude &cbp=1,yaw,,pitch,zoom&mz=mapZoom

End Sub


This should give you a start with working with GPS. From here

you could make a DB and save GPS locations then show the

distance between them and current position.

7. Project: GPS and the net SQL: Record

your position online Now we have two programs that can come together to make

something interesting. What if we were able to save our latitude

and longitude to an SQL database table on the net? Then we, or

someone else, could download those coordinates, and run them

through the Google maps to see where we are, or were. This is

easy to do.

Check back with the earlier program to get the finer details of what

we must do.

Here are the steps.

Create a new database table

1. Create a new table in your SQL database named GPSLocation make 5 fields

Set them as below.

You now have 2 tables in your database


Create a new PHP script

We could use the same PHP script we made before but lets make a new one so we can

keep it with our program in the same folder to make it easier updating. Copy and paste your

webDB.php file and save it as GPSLocation.php into your project.

Add a new function addgps

if($action == "addgps"){

$lat = $_GET['lat'];

$lon = $_GET['lon'];


mysql_query("INSERT INTO GPSlocation

(lat, lon, deviceid) VALUES('$lat', '$lon', '$deviceID') ")

or die(mysql_error());

}

We are using the INSERT command and this will make a new entry each time it saves.

However you might want to consider using an UPDATE command which will just change the

single saved GPS location if you only want to record the current location.

UPDATE table_name SET column1=value, column2=value2,... WHERE some_column=some_value

Use the Submit code from the last exercise to submit this to the DB.

First define the following under Sub Process_Globals

Dim phoneInfo As PhoneId


deviceID = phoneInfo.GetDeviceId ' getting the Phone ID

Dim httpC As HttpClient 'the Connection client

Initialise the HTTPC under Sub Activity_Create(FirstTime As Boolean)

httpC.Initialize("httpC")

Click on the HTTP library and the Phone Library to add it to the project.

Add the Menu button code to the Activity_Create

Activity.AddMenuItem("Upload Location", "uploadlocation")


Create a new sub, Sub uploadlocation_click that is the click event of the menu item

above, add the code full version below to it. And try it.

The 'sendrequest1 comment can be used to check if the php script is working, without

having to see if the rest is OK. Just change the request to req.InitializeGet(sendrequest1).

Here you can clearly see the 3 code blocks of Sending, Sub httpC_ResponseSuccess, and

Sub httpC_ResponseError needed to work with HTTP.

'SUBMIT GPS

Sub uploadlocation_click

‘variables to hold the lat and lon locations

Dim lat, lon As Double

lon = Currentloc.Longitude

lat = Currentloc.Latitude

‘Just a dialog to tell the user something is working

ProgressDialogShow("Submitting GPS ...")

‘Make a request


sendrequest = "http://android-dsed.host22.com/gpslocation.php?action=addgps&lat="

'sendrequest1 = "http://android-dsed.host22.com/gpslocation.php?action=addgps&lat=456&lon=123&deviceID=123456"

‘Sending the request

req.InitializeGet(sendrequest & lat & "&lon=" & lon &"&deviceID=" & deviceID)


‘Check to see what is going is OK

Activity.Title = lat &" "&lon &" " & deviceID

End Sub


‘show a message

ToastMessageShow("Success GPS uploaded", False)

‘Turn the dialog off

ProgressDialogHide

End Sub

Sub httpC_ResponseError (Response As HttpResponse, Reason As String, StatusCode As Int, TaskId As Int)

Msgbox("Error connecting to score server"&CRLF&CRLF&Reason,"Error ("&StatusCode&")")

ProgressDialogHide

End Sub


Your Database will show the details right. If your

program hasn’t picked up the location it will return 0.

That’s still OK its just a GPS issue rather than a coding

issue (hopefully).

Getting satellites

Sub GPS_GpsStatus (Satellites As List)

'This event allows you To display information about the currently available satellites. Note that Not all satellites in the List are actually used For calculating the last fix. So it Is possible that the List will include several satellites but still the reception Is Not good enough For a fix.

Dim SatCount As Int

SatCount = 0

For i = 0 To Satellites.Size - 1

'loop through counting satellites

Dim Satellite As GPSSatellite

Satellite = Satellites.Get(i)

If Satellite.UsedInFix = True Then SatCount = SatCount + 1

Next

lblsatt.Text = "Satellites In View: " & Satellites.Size & " Used: " & SatCount

End Sub


Retrieving data from the database and displaying distance to saved GPS location

We have the GPS location saved in the database and

now we want it back in the phone.

First we need the PHP code to call. I kept it simple by

using the same structure as the last exercise but changing the limit to 1. ORDER BY

TIMESTAMP DESC LIMIT 1 This means it takes the most recent entry only.

if($action == "getgps"){

$result = mysql_query("SELECT lat, lon, deviceID FROM GPSLocation ORDER BY TIMESTAMP DESC LIMIT 1" ) or die(mysql_error());



echo $row['lat'];

echo "\r\n".$row['lon'];


}

}

In Sub Activity_Create(FirstTime As Boolean) create a new menu item to use as

the click event.

We also want to create a new Location named SavedLocation that will allow me to get

distance and bearing from the current location to the saved location.

In Globals create the Location object Dim savedlocation As Location, and initialise it

in Activity Create below.

Activity.AddMenuItem("Download to GoogleMaps", "downloadgps")

savedlocation.Initialize()


Then in a new click event for the menu I put the following which by now is quite

straightforward calling the getgps function in the gpslocation.php above.

'GET THE GPS BACK INTO THE PHONE FROM THE DB

Sub downloadgps_click


req.InitializeGet("http://android-dsed.host22.com/gpslocation.php?&action=getgps")

'(req, 2) means it has a taskid of 2 see in the Sub httpC_ResponseSuccess


ProgressDialogShow("Fetching all data...")

End Sub

The result that is returned comes in via the httpC_ResponseSuccess. The pattern is the

same as the previous example. Read the data in line by line to a datafile, read it out to the

variables.

When we get the Lat and Lon, pass them to the savedlocation.Latitude to be used later. The

deviceID is downloaded but not used at this point. After getting the data we close the

reader with reader.Close.

Using the previous code for the GoogleMaps we pass the data to the maps. Finally with our

new SavedLocation we can see the distance from current GPS location to that point.


'(req, 1) means that taskID = 1 the upload function only

If TaskId = 1 Then

ToastMessageShow("Success GPS uploaded", False)

ProgressDialogHide

Else

'Any other function with a taskID of 2 - the download function

Dim result As String ‘result from the database being passed in


'write it to a file

File.WriteString(File.DirInternalCache, " gpsdownload.txt",result)


reader.Initialize(File.OpenInput(File.DirInternalCache, " gpsdownload.txt"))

Dim latgps As String ‘make a latitude variable to hold lat

latgps = reader.ReadLine ‘read the data to the variable

savedlocation.Latitude = latgps ‘save it also to the savedlocation object

Dim longps As String


longps = reader.ReadLine

savedlocation.Longitude = longps


deviceID = reader.ReadLine

reader.Close

Dim Intent1 As Intent

URI= "geo:" & latgps & "," & longps & "?q=" & latgps & "," & longps



StartActivity(Intent1)

Activity.Title = "Distance to location " & Currentloc.DistanceTo(savedlocation)& " in meters"

End Sub

Here is a pic of the Google maps showing the saved location at and the current location

with the blue Arrow. (Note this this pre earthquake so there are far more buildings and cars).

You can see on the title bar that the distance is 80.2 meters to the saved location.

As the distance has a ridiculous amount of decimal spaces in it lets round it off to 2 decimal

places. Round2(distloc, 2) is the primary code for this.

Dim distloc As Long

distloc = Currentloc.DistanceTo(savedlocation)

distloc = Round2(distloc, 2)

Activity.Title = "Dist to saved location " & distloc & " meters"


8. Project: Getting an address from a Geolocation using

XML As well as returning a map reference from lat and lon you can also use Google to return the

actual address of the place as well.

Instead of adding this ability to the last exercise I have left it as a stand alone project so that

you can add it in yourself, and see how it works. (Otherwise the code gets mixed up and

you never know what does what). Its your job to add it in.

The data that is returned comes down in an XML format and has to be parsed using

XMLSAX. SAX (Simple API for XML) is an event-based sequential access parser API

developed by the XML-DEV mailing list for XML documents to return XML to a useable

structure.

The edtgeo text field is only there so you can see the output returned from Google. You can

see in the code where it looks for the <formatted Address> field and extracts it to show in

the Message Box below.

If Name = "formatted_address" Then

'then pass the address details to the items list

Address = Text.ToString

Items.Add(Address)


Here is all the code and the libraries on the right

Sub Process_Globals

Dim GPS1 As GPS

Dim Parser As SaxParser 'Parser library

Dim hc As HttpClient 'Required to connect to the Internet


End Sub

Sub Globals

Dim lblLon As Label

Dim lblLat As Label

Dim lblSpeed As Label

Dim Button1 As Button

Dim edtgeo As EditText

Dim gLatitude As Float

Dim gLongitude As Float

Dim Address As String 'Variable to save the Address parsed

Dim Items As List 'A list to hold parsed items

End Sub


If FirstTime Then

GPS1.Initialize("GPS")

End If

Activity.LoadLayout("1") ' the layout is called 1 instead of main, just for variety

Parser.Initialize

hc.Initialize("hc")

Items.Initialize

'this formats up the text box to make it as big as possible.

edtgeo.Width = Activity.Width ' the width of the phone

edtgeo.Top = 250 ' 250 from the top to show the button etc

edtgeo.Left = Activity.left ' left hand side

edtgeo.Height = Activity.Height - 250 ' height of the phone - the 250

End Sub

Sub Activity_Resume

If GPS1.GPSEnabled = False Then

ToastMessageShow("Please enable the GPS device.", True)


StartActivity(GPS1.LocationSettingsIntent) 'Will open the relevant settings screen.

Else

GPS1.Start(0, 0) 'Listen to GPS with no filters.

End If

End Sub

Sub Activity_Pause(UserClosed As Boolean)

GPS1.Stop

End Sub

Sub GPS_LocationChanged(Location1 As Location)

gLatitude = Location1.Latitude

gLongitude = Location1.Longitude

'show the lat and lon on the labels

lblLat.Text = "Latitude = " & gLatitude

lblLon.Text = "Longitude = " & gLongitude

lblSpeed.Text = "Speed = " & Location1.Speed

'when you get a GPS fix then make the button show

If Location1.Latitude <> 0 AND Location1.Longitude <> 0 Then

Button1.Visible = True

End If

End Sub

Sub GPS_UserEnabled(Enabled As Boolean)

'just shows you have GPS enabled

ToastMessageShow("GPS device enabled = " & Enabled, True)

End Sub

Sub Button1_Click

Items.Clear 'Empty the list

edtgeo.Text = "" ' empty the text box

'send the request to the server

req.InitializeGet("http://maps.googleapis.com/maps/api/geocode/xml?latlng=" & gLatitude & "," & gLongitude & "&sensor=true")

hc.Execute(req, 1)

End Sub


If you get a result back then save it to a text file - File.OpenOutput(File.DirDefaultExternal,

"Geo.xml", False).

'GetAsynchronously (EventName As String, Output As java.io.OutputStream, CloseOutput

As Boolean, TaskId As Int) As Boolean

'EventName As String = GetGeoLocation

'Output As java.io.OutputStream = File.OpenOutput(File.DirDefaultExternal,

"Geo.xml", False)

'CloseOutput As Boolean = true

'TaskId As Int = taskID


Response.GetAsynchronously("GetGeoLocation",File.OpenOutput(File.DirDefaultExternal, "Geo.xml", False), True, TaskId)

End Sub



Msgbox("Connection Error", "")

Response.Release

End If

End Sub

Geolocation

'when the GetGeoLocation from the Response above has finished

Sub GetGeoLocation_StreamFinish(Success As Boolean, TaskId As Int)

Dim in As InputStream

'read the file into the input stream variable

in = File.OpenInput(File.DirDefaultExternal, "Geo.xml")

edtgeo.Text= File.ReadString(File.DirDefaultExternal, "Geo.xml")

'parse it through the parser and name the event as "Parser"

Parser.Parse(in, "Parser")' below are the start and end events of the parsing. Close the input stream

in.Close

'show the items list that is filled below in the Parser_EndElement

Msgbox(Items.Get(0), "")

End Sub

XML parser

The last two are happening at the start and the end of Parser.Parse(in, "Parser")

Sub Parser_StartElement(Uri As String, Name As String, Attributes As Attributes)

End Sub


Sub Parser_EndElement(Uri As String, Name As String, Text As StringBuilder)

'if there is Activity result (> -1)

If Parser.Parents.IndexOf("result") > -1 Then

'if the name (the string being parsed above) has in it formatted address

If Name = "formatted_address" Then

'then pass the address details to the items list

Address = Text.ToString

Items.Add(Address)

End If

End If

End Sub

9. Getting an error in your hc_ResponseSuccess? Fix the

taskID. If you are adding in new code that calls the internet into your program you may / will get an

error that we haven’t covered so far.

Each call to the internet via the HTTP used the code similar to hc.Execute(req, 1). The 1 is

the taskID that is passed to the hc_ResponseSuccess. You see it being passed as TaskId

As Int.

Sub hc_ResponseSuccess(Response As HttpResponse, TaskId As Int).

Multiple calls to the net all return through the same subroutine above and regardless of what

they do will work with every line of text in there. To prevent errors occurring, which they will,

we need to change our taskID for each request.

So 3 calls to the net for different processes will look like this….

hc.Execute(req, 1). …

hc.Execute(req, 2).

hc.Execute(req, 3).

Then in your hc_ResponseSuccess bracket your response code with the appropriate taskID

Sub hc_ResponseSuccess(Response As HttpResponse, TaskId As Int).

If taskID = 1 then

End if

If taskID = 2 then

End IF

If taskID = 3 then

End if


10. Project: Creating a Weather Widget Widgets are the little programs that run on the front of your phone. They are active

programs, and more than just shortcuts that open the program.

Widgets are created and managed in another process, different than the process that your

application is running in. So its not just a front end of your

program and they run when your program has turned off. They

use a Service Module rather than the Activity Module that we

are used to. Each widget is tied to their own Service Module.

Through this module the widget is created and updated.

In this case we are making the Widget alongside the same

temperature program we made previously, but it could be in

a new program. The program only shares the text file that holds

the city selected.

The home screen application (the front of your phone) hosts your widgets and means that it

is not possible to directly access the widgets views. Instead we use a special object named

RemoteViews which gives us indirect access to the widget views.

Widgets do not support all views types. The following views are supported:

- Button (default drawable)

- Label (ColorDrawable or GradientDrawable)

- Panel (ColorDrawable or GradientDrawable)

- ImageView

- ProgressBar (both modes)

All views only support the Click event.

To make a widget we have to add a Service module. Note that the service module

handling the widget is a standard service. Design the widget layout with the designer.


The Service Module

Create a Service module by going Project / Service Module. Name it ServiceWidget

A Service Module is good for scheduling a repeating task. By calling StartServiceAt you

can schedule your service to run at a specific time. You can call StartServiceAt in Sub

Service_Start to schedule the next time and create a repeating task (for example a task

that checks for updates every couple of minutes).

You can also run a service after the phone boots by checking Project - Service properties -

Start At Boot your service will run after boot is completed.

The Service Module has familiar areas to the Activity Module we have used to date.

Sub Process_Globals is the place to declare the service global variables. There is no

Globals sub like in Activity as Service doesn't support Activity objects. Sub process globals

should only be used to declare variables.

Note that Process_Global variables are kept as long as the process runs and are accessible

from other modules.

Sub Service_Create is called when the service is first started. This is the place to initialize

and set the process global variables. Once a service is started it stays alive until you call

StopService or until the whole process is destroyed.

Sub Service_Start is called each time you call StartService (or StartServiceAt). When

this subs runs the process is moved to the foreground state. Which means that the OS will

not kill your process until this sub finishes running. If you want to run some code every

couple of minutes / hours you should schedule the next task with StartServiceAt inside this

sub.

Sub Service_Destroy is called when you call StopService. The service will not be running

after this sub until you call StartService again (which will run Sub Service_Create followed

by Sub Service_Start).


A Standard template for a Widget in the Service Activity

Sub Process_Globals

Dim rv As RemoteViews

End Sub

Sub Service_Create

rv = ConfigureHomeWidget("LayoutFile", "rv", 0, "Widget Name")

End Sub

Sub Service_Start (StartingIntent As Intent)

If rv.HandleWidgetEvents(StartingIntent) Then Return

End Sub

Sub rv_RequestUpdate

rv.UpdateWidget

End Sub

Sub rv_Disabled

StopService("")

End Sub

Sub Service_Destroy

End Sub

The code below is in the order that it can be placed on the Service Activity

Open your weather program and add a Service Module to it. Then add in the code.

'Service module

Sub Process_Globals


Dim hc, hcimage As HttpClient

Dim req, reqimage As HttpRequest

Dim temp, strplace, townpath, pic, selectedcity, temperature As String

Dim oldtemp As Short : oldtemp = 0 ' holds the old temperature

End Sub


ConfigureHomeWidget("wlayout", "rv", 0, "Temp Widget 26-4")

The four parameters are: layout file, event name, update interval and the widget name.

Widget name = the name that will appear in the widgets List.

Event name sets the subs that will handle the RequestUpdate AND Disabled events.

You can configure the widget and set it to update every 24 hours (1440 minutes). The

interval, measured in minutes, defines how often will the widget request To update itself. Set

To 0 To disable automatic updates. Updating the widget too often will have a bad impact on

the battery. The minimum value Is 30 minutes. We can use a timer to get a shorter interval.

Sub Service_Create

rv = ConfigureHomeWidget("wlayout", "rv", 0, "Temp Widget 26-4")

hc.Initialize("hc")

hcimage.Initialize("hcimage")

GetTemp

End Sub

This checks the Intent message that caused this Service To start and is responsible for

raising the events related to the widget. It returns True If an event was raised.



End Sub

The widget raises two events. RequestUpdate is raised when the widget needs to update

itself. It will fire after adding the widget to the screen, after the device has booted, based on

the scheduled updating interval (If set) or after the application was updated.


GetTemp

End Sub

Sub rv_Disabled

StopService("")

End Sub

Sub imgNext_Click ‘click event of the image

GetTemp

End Sub

Sub panel1_click ‘click event of the panel

GetTemp

End Sub


This is the main sub of the widget. I will comment it throughout the code. This is mostly the

same code as we used in our earlier exercise.

Sub GetTemp

‘we call the selected city that has been stored in the text file of the weather program

selectedcity = File.ReadString(File.DirInternal, "WeatherCity.txt")

‘What if there isn’t anything in the text file? Give it a default city

If selectedcity = "" Then

selectedcity = "Auckland"

End If

‘We want to get two temperatures, the current temp from the internet, and the old temp from before the update. This means you can tell if the temp is going up or down.

If temperature <>"" Then ‘if there is a temp then pass it to oldtemp before getting a new temp

oldtemp = temperature

End If

strplace = selectedcity.ToLowerCase


'Just to show its updating make the temp in the label go away and make a message show

rv.SetText("lbltemperature", "")

rv.SetText("lbltime", "Updating ...")

‘Update the widget

rv.UpdateWidget


hc.Execute(req, 1)

End Sub

Sub Service_Destroy

End Sub


Dim temp As String


'Cut beginning and end to get the code for the temp itself

temp = temp.SubString(temp.IndexOf("<div class=" & QUOTE & "summary" & QUOTE & ">")) 'cut to first occurrence of

temp = temp.SubString2(21, temp.IndexOf("</ul></div></div>")) 'find last occurance of

temp = temp.Replace(QUOTE,"'") ' replace double with single quotes

'pull the city from the code

Dim city As String


city = temp

'start at the 4th letter and end with the /h1

city = city.SubString2(4, city.IndexOf("</h1>"))

temperature = temp 'pull the temperature from the code

temperature = temperature.SubString(temperature.IndexOf("ul'><h2>"))

temperature = temperature.SubString2(8, temperature.IndexOf("<span "))

Dim shtemp As Short

shtemp = temperature

'get the difference between the old temp and the new temp

Dim updowntemp As Short

updowntemp = shtemp - oldtemp

'set the colors red = up blue = down white no change

Dim temptext As String

If updowntemp > 0 Then

temptext = " Up"

rv.SetTextColor("lbltemperature", Colors.RGB(255,204,225))

Else

temptext = " Down"

rv.SetTextColor("lbltemperature", Colors.RGB(141,197,224))

End If

If updowntemp = 0 Then

temptext = ""

rv.SetTextColor("lbltemperature", Colors.White)

End If

'remote view passes the data to the label

rv.SetText("lbltemperature", temperature)

pic = temp 'pull the pic from the code

pic = pic.SubString(pic.IndexOf("wx-icons/")) 'start position

pic = pic.SubString2(9, pic.IndexOf("' width")) ' 6 is the number from counting the letters above

pic = pic.Trim

'looking for the image, is it already in the cache?

If File.Exists(File.DirInternalCache, pic) Then

'if so then load it, show the imgnext view and load an image into it

rv.SetVisible("imgnext", True)

rv.SetImage("imgnext", LoadBitmap(File.DirInternalCache, pic))

Else

Getimage 'otherwise go and get it from the net


End If

Dim strtime As String 'pull the time from the code

strtime = temp

Dim timecolon As String

timecolon = strtime.IndexOf(":") 'find the colon between the time eg 11:23am

strtime = strtime.SubString2(timecolon -2, timecolon +5) 'take 2 off and add 5 on to get the whole time 11:23am

rv.SetText("lbltime", strtime & CRLF & city & temptext)

rv.UpdateWidget

End Sub

Sub getimage

Dim imagepath As String 'this gets the image from the net

imagepath = "http://m.metservice.com/sites/all/themes/mobile/images/wx-icons/"& pic

reqimage.InitializeGet(imagepath)

hcimage.Execute(reqimage, 1)

End Sub

Sub hcimage_ResponseSuccess(Response As HttpResponse, TaskId As Int)

Response.GetAsynchronously("ImageResponse", _

File.OpenOutput(File.DirInternalCache, pic, False), True, TaskId)

End Sub

Sub ImageResponse_StreamFinish (Success As Boolean, TaskId As Int)

If Success = False Then

Msgbox(LastException.Message, "Error")

Return

End If

rv.SetImage("imgnext", LoadBitmap(File.DirInternalCache, pic))

End Sub

Sub hcimage_ResponseError(Response As HttpResponse, Reason As String, StatusCode As Int, TaskId As Int)



Response.Release

ProgressDialogHide

ToastMessageShow("Image not loading",True)

End If

End Sub





Response.Release

ProgressDialogHide


End If

End Sub


Designing the Temperature Widget

This is a small layout so will be tricky to show. This is

a NEW LAYOUT. Not part of the existing one that the

Activity used.

It has 5 parts.

Pnlbg – a transparent panel to space the widget out from the other widgets

Panel1 – a visible graduated

panel

Imgnext – a small imageview

to hold the pic

Lbltime – holds time and City

Lbltemperature – holds the

temperature.


This is a white square behind the temperature that is curved like a circle, its hard to make

out unless you see the entire widget.


Back on your phone click your menu button (bottom left blank space on mine and click on

Add. Then click on Widgets and drag onto the phone the one we have created.


11. Project: Alarm scheduler sends

email to contacts This program incorporates four main areas,

An alarm which is created with date and time.

The ability to extract your contacts list from your phone

The ability to send SMS messages

Working with Lists

Imagine you wanted to send a message to some people in your contacts list

at a set time every day. This program does that.

There are two Modules, a Main Activity module and a Service Module. The

main module sets up the program while the service module runs when the

alarm time equals the cell phone time.

'Activity module

Sub Process_Globals

Dim alarmHours, alarmMinutes As Int

Dim noti As Notification 'shows in the notification window

End Sub

Sub Globals

Dim SetTime As Button

Dim CancelAlarm As Button

Dim lvphone As ListView

Dim btnSavephone As Button

Dim Panel1 As Panel

Dim btnloadlist As Button

Dim edtmessage As EditText

Dim phonelist As List

Dim listOfContacts As List

End Sub



getcontacts

listOfContacts.Initialize ‘using a List

phonelist.Initialize

End Sub


Date and Time

Main Sub to get the alarm time. (Note that Alarm isn’t defined that’s because I don’t know

what type it is. It still works, just gives a nice red color).

Sub SetTime_Click

Dim td As TimeDialog 'the dialog from the dialog library

td.Hour = alarmHours

td.Minute = alarmMinutes

If td.Show("Select time to activate alarm", "", "Ok", "Cancel", "", Null) = DialogResponse.POSITIVE Then

alarmHours = td.Hour

alarmMinutes = td.Minute

Dim today As Long

today = DateTime.DateParse(DateTime.Date(DateTime.Now)) 'Sets today at 12:00 AM

alarm = today + td.Hour * DateTime.TicksPerHour + td.Minute * DateTime.TicksPerMinute

If alarm < DateTime.Now Then alarm = DateTime.Add(alarm, 0, 0, 1)

Log(DateTime.Date(alarm) & " " & DateTime.Time(alarm)) 'check the logs to see the set date and time

'Calculate time to alarm

Dim h, m As Int

h = Floor((alarm - DateTime.Now) / DateTime.TicksPerHour)

m = ((alarm - DateTime.Now) - h * DateTime.TicksPerHour) / DateTime.TicksPerMinute

ToastMessageShow("Alarm will start after: " & NumberFormat(h, 2, 0) & " hour(s) and " & NumberFormat(m, 2, 0) & " minute(s)", True)

'You should schedule the next task with StartServiceAt.Android will eventually kill your process if you use a timer. By scheduling the Next task with StartServiceAt you make sure that a new process will be created when the scheduled time arrives. This Is Not the Case with a regular Timer.

StartServiceAt(AlarmService, (DateTime.Now+((h*60*60*1000)+(m*60*1000))), True) ' Schedule AlarmService will start by add time to DateTime.Now (note that Android use millisecond)

‘This sets out the notification features that appear on the notification front part of your phone

noti.Initialize

noti.Light = True

noti.Vibrate = False


noti.OnGoingEvent = True

noti.Sound = False

noti.Icon = "icon" ‘ set your own image if you want

noti.SetInfo("Alarm", "will start at " & DateTime.Date(alarm) & " " & DateTime.Time(alarm), "")

noti.Notify(1) ‘Displays the notification. Id This id can be used to later update this notification (by calling Notify again with the same Id), or to cancel the notification.

End If

End Sub

Turn off the alarm

Sub CancelAlarm_Click

noti.Cancel(1) ‘This cancels the Notification number 1 set above

StopService(AlarmService)

CancelScheduledService(AlarmService)

End Sub

Main sub to get the contacts from the Phone I left the commented out section in case you

want to see whats happening, and grab them yourself

Sub getcontacts

Dim Contacts2 As Contacts2

listOfContacts = Contacts2.GetAll(True,False)

For i = 0 To listOfContacts.Size - 1

Dim Contact As Contact

Contact = listOfContacts.Get(i)

'Logging to check how it works can uncomment

Log(Contact) 'will print the fields to the LogCat

' Dim photo As Bitmap

' photo = Contact.GetPhoto

' If photo <> Null Then Activity.SetBackgroundImage(photo)

' Dim emails As Map

' emails = Contact.GetEmails

' If emails.Size > 0 Then Log("Email addresses: " & emails)

' Dim phones As Map

' phones = Contact.GetPhones

' If phones.Size > 0 Then Log("Phone numbers: " & phones)

If Contact.PhoneNumber <>"" Then ‘ If there is a contact number pass it to the listview so you can see it

lvphone.SingleLineLayout.Label.TextSize = 15

lvphone.SingleLineLayout.ItemHeight = 40

lvphone.AddSingleLine(Contact.DisplayName &": " &Contact.PhoneNumber)

lvphone.ScrollingBackgroundColor =Colors.DarkGray

End If

Next


End Sub

This is the click event on the listview. We want to take the value that we click on (the name

and phone number) and add it to our Phonelist as a List object.

Sub lvphone_ItemClick (Position As Int, Value As Object)

‘pass the value to details and then save it to the phone list. Might be able to bypass all this and just go phonelist.Add(Value)

Dim details As String

details = Value

Activity.Title = details ‘Show the name at the top as a check

Log(details) ‘Show the name in the logs as a check

phonelist.Add(details)

End Sub

Write to a file

The button save click saves two parts, the message that you want sent, and the phone list

that you have created. These text files are then opened and used by the service when the

alarm is activated.

Note the easy File.WriteString(File.DirInternal, "message.txt", edtmessage.text) structure.

Of Filename "message.txt" and Content. edtmessage.text.

Sub btnSavephone_Click

‘Check to see if a message has been written and a list has been made

If edtmessage.text <>"" AND phonelist.Size >0 Then

‘Write the message and list to files to be accessed later

File.WriteString(File.DirInternal, "message.txt", edtmessage.text)

File.WriteList(File.DirInternal, "phonelist.txt", phonelist)

ToastMessageShow("List saved", False)

lvphone.Clear ‘ clear the listview screen ready to show its saved

Else

‘bozo notification

ToastMessageShow("Save a list and write a message first", True)

End If

End Sub

Read from a file to a list

This button allows you to load the list you made to check that it’s the correct people in it.

This shows how easy a list is to use as well.

Sub btnloadlist_Click

Dim list1 As List

‘quit if no phonelist (If statements don’t need an endif they are only on one line.)

If File.Exists(File.DirInternal, "phonelist.txt") = False Then Return


‘pass the data to the list

list1 = File.Readlist(File.DirInternal, "phonelist.txt")

‘Here is the data being looped into the list

Dim j As Int

j = list1.Size ‘make J the size of the list

If j < 0 Then Return

For i = 0 To j-1 ‘add each item to the listview

lvphone.AddSingleLine(list1.Get(i))

Next

End Sub

'Service module

Sub Process_Globals

Dim mp As MediaPlayer ' You need to declare mp as Mediaplayer

Dim noti As Notification ‘make a new notification

End Sub

Sub Service_Create

End Sub

Sending an SMS

In this module the heart is Sms.Send(phonelist, messagetext) which is commented out

so you don’t lose all your friends while building it.

Sub Service_Start

mp.Initialize() 'Initialize Mediaplayer

PlayAlarm ‘run the play alarm sub

ToastMessageShow("Emails sent", True) ‘ emails sent

'LOAD LIST

Dim list1 As List

Dim messagetext As String

Dim j As Int

Dim phonelist As String

If File.Exists(File.DirInternal, "phonelist.txt") = False Then Return

list1 = File.Readlist(File.DirInternal, "phonelist.txt")

‘note this is ReadString as its only one word not a list

If File.Exists(File.DirInternal, "message.txt") = False Then Return

messagetext = File.ReadString(File.DirInternal, "message.txt")

j = list1.Size

If j < 0 Then Return

For i = 0 To j-1

‘the phone list consists of Name: number we only want number to send the message (although we could use the name in the message field if were


wanted). So we have to do our chopping the string at : to get the number from it

phonelist = list1.Get(i)

phonelist = phonelist.SubString2(phonelist.IndexOf(":")+2, phonelist.Length)

Log(phonelist) ‘check to see it working

ToastMessageShow(list1.Get(i)&" " & phonelist & " " & messagetext, False)

Dim Sms As PhoneSms

Dim number As PhoneId

Dim senttext As String

'Send (PhoneNumber As String, Text As String)

'Sms.Send(phonelist, messagetext)

Next

noti.Initialize

noti.SetInfo("message sent",messagetext,"")

End Sub

End the Service

Sub Service_Destroy

StopService("") 'Stop this service

CancelScheduledService("") 'Cancel this service

End Sub

Play the alarm

Sub PlayAlarm

mp.Load(File.DirAssets, "sound.wav")

mp.Play

End Sub


12. Project: Text to Speech Program The beauty of this simple little program is not in its novelty value, but that it can be added to

any other program to add functionality and make a point of difference. Imagine you add it to

your Weather Widget, or your GPS locator, so that people can just click on the program and

hear the temperature and location without taking their eyes off the road.

As well it could be the heart of a program for disabled people, and later we will use it to read

emails as well.

Note that the text read is held in the edttext.text field, which

means that any strings can be read as well.

Sub Process_Globals

Dim TTS1 As TTS

End Sub

Sub Globals

Dim barPitch As SeekBar

Dim barSpeechRate As SeekBar

Dim btnSpeak As Button

Dim EditText1 As EditText

Dim spnrLanguages As Spinner

End Sub


Activity.LoadLayout("1")

spnrLanguages.AddAll(Array As String("en", "fr", "de"))

'As TTS doesn't support the volume control - you can't change the volume - you need to use Reflector to get the Music volume, which is louder I suppose, and use that instead.

Dim r As Reflector

r.Target = r.GetActivity

r.RunMethod2("setVolumeControlStream", 3, "java.lang.int")

End Sub

Sub TTS1_Ready (Success As Boolean)

If Success Then

'enable all views

For i = 0 To Activity.NumberOfViews - 1


Activity.GetView(i).Enabled = True

Next

btnSpeak_Click 'play first sentence

Else

Msgbox("Error initializing TTS engine.", "")

End If

End Sub

Sub Activity_Resume

If TTS1.IsInitialized = False Then

TTS1.Initialize("TTS1")

End If

End Sub


TTS1.Release

End Sub

Sub btnSpeak_Click

If EditText1.Text.Length > 0 Then

TTS1.Speak(EditText1.Text, True)

EditText1.SelectAll

End If

End Sub

Sub barSpeechRate_ValueChanged (Value As Int, UserChanged As Boolean)

If UserChanged Then

TTS1.SpeechRate = Value / 10

End If

End Sub

Sub barPitch_ValueChanged (Value As Int, UserChanged As Boolean)

If UserChanged Then

TTS1.Pitch = Value / 10

End If

End Sub

Sub spnrLanguages_ItemClick (Position As Int, Value As Object)

If btnSpeak.Enabled = False Then Return

If TTS1.SetLanguage(Value, "") = False Then

ToastMessageShow("Language data not found.", True)


Return

End If

End Sub

Text to speech – stripped for other programs

Here is the stripped down version that you can just drop into your programs. Don’t forget to

add the TTS library.

It doesn’t have to come off the button click, that’s just an example.

Dim TTS1 As TTS

Sub Activity_Resume



TTS1.SetLanguage("en","")

End If

End Sub


TTS1.Release

End Sub

Sub Button1_Click

If .yourtext.Text.Length > 0 Then

TTS1.Speak(yourtext.Text, True)

End If

End Sub


13. Project: Capture all SMS messages entering your

phone Imagine that when a text message came into your phone that you didn’t have to stop what

you are doing and have to look to see who sent it. Maybe you are driving, working, or busy

elsewhere and want to know if its important or not.

That’s what this program does. It tells you who sent the text message so you can decide if

you need to reply immediately. This is based on the previous lessons and looks at a few of

the many features of the phone you can use in programming.

When a text message comes in the number it comes from is checked against the contacts

list in your phone. If a match is made then it speaks out the name of the person in the

contact list.

For this to work you need to have the Phone library 1.8 installed. To do that download it from B4A website, and put it into the internal library folder, not the usual external one. The internal folder is usually at C:\Program Files\Anywhere Software\Basic4android\Libraries

If you have a Phone library in the external library then you need to delete it as it will

overwrite the internal Phone Library.

Logs and Toastmessageshow are crucial to debugging

Debugging is crucially important and especially so in this exercise. I have used copious

amounts of Logs and Toastmessageshow to see what is happening in the code. What is the

number coming in? How does it change when you strip it? Does it match up with the

contacts? What happens next etc.

You need to do this as well. Debugging IS coding. Not just following this exercise.


Working with Service and Activity Modules

This project has 2 main parts. An Activity Module (Main) that

holds the code for the screen above, and a Service Module

(sms) that runs all the time and listens for incoming text

messages. Another Activity module smstext holds a data file,

but its not important

I think of the Activity Module (main). as my test bed, I get the Activity module working first,

and then when its all OK I make the Service Module (sms). That’s because it’s easier to

think and code in the activity module and to see what you are doing and you can have

sample test data.

In this exercise I copied all the working code from the Activity Module to the Service module,

did final changes and moved the changed code back in to the Activity Module to check it.

Saving and Reading to files

When working with a Service module you need to pass data to it from the Activity module

using text files. So if you make a setting in your activity module, you have to save it as a text

file then upload it into the service module. That way the settings are saved when you turn off

your program and only the service is running.

Saving and reading from text files is really easy, and I use it throughout the code.

Here for example is data held in the details variable being written to a file "from.txt"

From = File.WriteString(File.DirInternal, "from.txt",details)

And here is the data from that "from.txt" file being passed back into the From variable.

From = File.ReadString(File.DirInternal, "from.txt")

Its fast and easy.

The Activity (main) code

'Activity module

Sub Process_Globals

Dim TTS1 As TTS 'text to speech

End Sub

Sub Globals

Dim lvphone As ListView 'the listview holding the contacts

Dim edtmessage As EditText 'messagebox that holds the phone number

Dim Panel1 As Panel ' background panel

Dim Button1 As Button ' the Simulator run button

Dim listOfContacts As List 'holds the contacts list

Dim btnservicestart As Button ' start the service button

Dim btnservicestop As Button 'stop the service button

End Sub



Activity.LoadLayout("main") ' load the main layout

StartService(Sms)

If TTS1.IsInitialized = False Then ' turn on text to speech and set the language


TTS1.SetLanguage("en","")

End If

getcontacts ' load the contacts into the listview

End Sub

Sub Activity_Resume

End Sub


End Sub

Sub MessageReceived (From As String, Body As String) As Boolean

Msgbox("From " & From & " Text " & Body, "Title")

End Sub

'this sumulates a text arriving

Sub Button1_Click

smscopy ' copy of the sms activity code modified for the activity runs

End Sub

'fills the listview with the data from the contact list

Sub getcontacts

'Create a Contacts to hold the contacts from your phone. Contacts2 object allows you to access the device stored contacts. This type is based on a new API supported by Android 2.0 and above.This type supersedes Contacts type.


'pass the contacts to a list to hold them. Note that each contact has about 6 or so fields, that at the moment you can't get to


'loop through each of the contacts in your new list


'for each contact pass it to the Contact object. This object allows you to extract out each field held in filed, so you can use Contact.phonenumber and Contact.DisplayName as well as many others.




'Logging to check how it works

Log(Contact) 'will print the fields to the LogCat

'We don't want contacts who don't have a phone number or contacts with short number such as your phone provider. A 3 digit number will screw with the next part of the code where we cut the beginning off.

If Contact.phonenumber <>"" AND Contact.phonenumber.Length > 7 Then

'show the name and number from the contacts list in your listview and format it up to make it easy to read

lvphone.SingleLineLayout.Label.TextSize = 15

lvphone.SingleLineLayout.Label.TextColor = Colors.Black

lvphone.SingleLineLayout.ItemHeight = 40

lvphone.ScrollingBackgroundColor =Colors.Transparent

'data goes in here the name and number separated by a :, this is what we use to get the name out later.

lvphone.AddSingleLine(Contact.DisplayName &": " & Contact.phonenumber)

End If

Next

End Sub

Clicking on the listview

Sub lvphone_ItemClick (Position As Int, Value As Object)

'strip out the name and leave the number and write it to the FROM text file. its broken out at the :

Dim details As String

details = Value

details = details.SubString2(details.IndexOf(":")+2, details.Length)

'write the number in the text box

edtmessage.text = details

'write the number to the from.txt file

File.WriteString(File.DirInternal, "from.txt",details)

End Sub

Sub btnservicestop_Click

StopService(Sms) ' stop the service running (turn it off)

End Sub

Sub btnservicestart_Click

StartService(Sms) ' start the service running (turn it on)

End Sub


'I called this smscopy as its a copy of the sms main code

Sub smscopy

'this reads the file in from the from.txt. in the sms code it comes in via the sms message

Dim From As String

From = File.ReadString(File.DirInternal, "from.txt")

'logs and toastmessages to see what is happening

ToastMessageShow("Text from " & From, True)

Log ("From before cut" & From)

'strips out the first numbers of the incoming phone number. The number coming into the phone can have different prefixes on it to the one stored in the phone. eg: number in is always 642.. country code and cellphone, but the number in the contacts can be just cellphone 027.. we need to make both equal. So stripping out the first numbers down to 7 digits fixes this. Thats why empty entries and ones with 3 numbers are blocked earlier, it crashes here. (took me hours to work out).

' From.Length-7 find the length of the number eg: 11, take of 7 and = 4, so start number for the substring is 4.

'SubString2(startnumber, to end number)

From = From.SubString2(From.Length-7, From.Length)

'show me the chopped number as a check

ToastMessageShow("Chopped from " & From, True)

'same code as above getting the contacts2 list, passing it to a listofcontacts and a contacts object to extract out the name and number.







'just to see what the counter is doing

Log(i)

Dim phonenumber As String

Dim startphone, endphone As Int



'this strips out the first numbers of the phone list. its the same as we did above but I broke it down into its component parts to make it easier for you to read

phonenumber = Contact.phonenumber

startphone = phonenumber.Length-7

endphone = phonenumber.Length

phonenumber = phonenumber.SubString2(startphone,endphone)

Log ("From after the cut" & From)

If From = phonenumber Then

'a whole bunch of testing going on

' ToastMessageShow("PH " & phonenumber & " From " & From, True)

Log("PH " & phonenumber & " From after cut " & From)

ToastMessageShow("Incoming text from " & Contact.Name, True)

'text to speech finally working

TTS1.Speak("Text from " & Contact.Name, True)

'this text file holds the name and message, it will go on the widget so you can read it

File.WriteString(File.DirInternal, "body.txt","From " & Contact.Name &" This is a test message, Its a really long one, I hope you can read it all")

Else

'ToastMessageShow("No matching contact", True)


End If

End If

Next

End Sub


Code for the Service Activity(sms)

'Service module

Sub Process_Globals

Dim SI As SmsInterceptor

Dim TTS1 As TTS

'remote view for the widget RV is how the widget communicates with the service and visa versa as we don't DIM or pass variables


End Sub

Sub Service_Create

'starting the service in the foreground means it won't get killed by the Android system - it stays alive

Service.StartForeground(1,"SMSInterceptor running")

'You intercept SMS messages and prevent the messages from being handled by the default messaging application by initializing SmsInterceptor with Initialize2 AND setting the Priority parameter To 999 (highest application priority For Intent filters).

'This then handles the Sub SI_MessageReceived part

SI.Initialize2("SI", 999)

'make sure text to speech is initialised and set the details



TTS1.SetLanguage("en","")'language

End If

Log("Service initialized")

'Widget name - the name that will appear in the widgets List.

rv = ConfigureHomeWidget("smslayout", "rv", 0, "SMS Inteceptor")

End Sub


'setting out the notification features of the phone

Dim noti As Notification 'shows in the notification window

noti.Initialize

noti.Icon = "icon"

'noti.Notify(1)

noti.Sound=False

noti.Vibrate = False

noti.Light = False

'this runs the next Activity (smstext)

noti.SetInfo("SMS Interceptor","Running", "smstext")

Service.StartForeground(1, noti)

ToastMessageShow("SMS inteceptor has started", False)


'This code checks the Intent message that caused this service to start in this case the text message recieved and is responsible for raising the events related to the widget. It returns true if an event was raised.


End Sub

Sub Service_Destroy

SI.StopListening()

Service.StopForeground(1)

ToastMessageShow("SMS inteceptor has stopped", False)

End Sub

'The heart of the program

Sub SI_MessageReceived (From As String, Body As String) As Boolean

'Body and From are the two parts of the text message that are passed into the phone from the incoming sms

ToastMessageShow("Text from " & From, True)

Log ("From before cut" & From)

'strips out the first numbers of the incoming phone number

From = From.SubString2(From.Length-7, From.Length)

'ToastMessageShow("Chopped from " & From, True)







'this strips out the first numbers of the phone list

Dim phonenumber As String

Dim startphone, endphone As Int


phonenumber = Contact.phonenumber

startphone = phonenumber.Length-7

endphone = phonenumber.Length

phonenumber = phonenumber.SubString2(startphone,endphone)

Log ("From after the cut" & From)

'write a file to open with the widget


File.WriteString(File.DirInternal, "body.txt","From " & From & " " & Body)


' ToastMessageShow("PH " & phonenumber & " From " & From, True)


ToastMessageShow("Incoming text from " & Contact.Name, True)

TTS1.Speak("Text from " & Contact.Name, True)

File.WriteString(File.DirInternal, "body.txt","From " & Contact.Name & " " & Body)

Else

'ToastMessageShow("No matching contact", True)


End If

End If

Next

updateTheWidget

End Sub

'this loads the widget with the updated information

Sub updateTheWidget

Dim message As String

message = File.ReadString(File.DirInternal, "body.txt")

If message <>"" Then

‘show the message on the lbltext on the widget

rv.SetText("lbltext", message)

Else

rv.SetText("lbltext", "No message")

End If

'update the widget action

rv.updatewidget

End Sub

'click on the panel to update the widget

Sub pnlcolor_click

updatewidgettext

End Sub

Sub updatewidgettext

rv.SetText("lbltext","Working ...")

ToastMessageShow("Click event on lblclick?", True)




If message <>"" Then

‘show the message on the lbltext on the widget

rv.SetText("lbltext", message)

Else

rv.SetText("lbltext", "No message")

End If

rv.updatewidget

End Sub


rv.updatewidget

End Sub

Sub rv_Disabled

StopService("")

End Sub

The Activity(smstest)

This activity is just a tacked on piece, its working code but I think it might be better used

elsewhere. What I was trying to do is when a message is received and the Notification is

activated a text is placed in the Notification window.

This is loaded in with the code from the Service

'this runs the next Activity (smstext)

noti.SetInfo("SMS Interceptor","Running", "smstext")

If we want to see what the message is then we can click on the notification and it will run the

"smstext" activity which loads the messagebox with the message.


Sub Globals

End Sub


If File.Exists(File.DirInternal, "body.txt") = False Then

ToastMessageShow("No message", False)

Else



Msgbox(message, "latest message")

End If

Activity.Finish

End Sub

Sub Activity_Resume

End Sub


End Sub

Designing the Widget

This widget is almost exactly the same as the last widget we made.

We have the following

Pnlbg – transparent background panel

Pnlcolor – color panel with curved corners

Lbltext – holds the text of the message

IVimage – holds the icon.


14. Project: Voice Recognition program This simple little program is easy to create and can add variety and value to your Android

programs.

All it requires is a layout with a button on it. The VR program generates its own interface.

The button doesn’t have to be as big as it is it does not affect the VR layout.

We will use this program later back in our last program to allow you to talk in commands to

create text messages mostly by just adding this entire activity as a new activity to the

program.

Designer Running

Google VR Program runs generating

its own interface


'Activity module

Sub Process_Globals

Dim VR As VoiceRecognition

Dim TTS1 As TTS

End Sub

Sub Globals

End Sub


If FirstTime Then

VR.Initialize("VR")


End If

'load the layout named 1 (just a button)

Activity.LoadLayout("1")

'tells the user if they can use voice recognition

If VR.IsSupported Then

ToastMessageShow("Voice recognition is supported.", False)

Else

ToastMessageShow("Voice recognition is not supported.", True)

End If

'just a text message on the program neat the top

VR.Prompt = "Say your message"

End Sub

Sub Button1_Click

VR.Listen 'calls the voice recognition external activity

End Sub

Sub VR_Result (Success As Boolean, Texts As List)

'Texts is a list object, the VR program creates a list of potential phrases it hears ie: You say "Today is hot" it lists "Today is not", "Today is snot" "Today is a lot" etc, then lists it in order of preference and at Texts.Get(0)gives the most likely choice "Today is Hot".

If Success = True Then

ToastMessageShow(Texts.Get(0), True)

TTS1.Speak(Texts.Get(0), True)

End If

End Sub


15. Project: Voice recognition in SMS messages

program. The addition of voice recognition is actually pretty easy. Rather than writing the code from

scratch and embedding it into the existing program I merely copy it over to a new activity

and then connected it through via the click on the widget icon that loads a button.

First of all lets get it working in your testbed the Main Activity then when all the

bugs are ironed out make a link in your Service (SMS) Module.

Create a transparent layout – a floating button

We need a layout for the button to be clicked to activate the voice recognition. Its only one

button on a Layout. The new layout is called Voice.

Go to the manifest Editor – Project / manifest Editor

In the manifest editor add the line to the bottom. (It’s all one line except for the comment)

'The line below needs to be added to make the activity transparent

SetActivityAttribute(voice1, android:theme, @android:style/Theme.Translucent.NoTitleBar)

Voice1 is the name of the new Activity we will make, not the name of the layout.


When activated the button will appear to float over the top of the window, but in reality it just

has a transparent background.

At this stage we can’t test it and see, you will just have to trust me.


The Voice Recognition Activity Module

Back in the program go Project / Add New Module / Activity Module. Then create new

Activity Module named Voice1.

This activity module is a copy of the earlier exercise with added sections. The two new parts

are Sub smstextready which loads the SMS reply window ready for a message and Sub

readtext that reads back the incoming SMS message.

'Activity module

Sub Process_Globals

Dim vr As VoiceRecognition ' first time

Dim vrtext As VoiceRecognition ' for message

Dim TTS1 As TTS

End Sub

Sub Globals

'if people get it wrong, lets insult them.

Dim insult As Int :insult = 0

End Sub


If FirstTime Then

vr.Initialize("VR")

vrtext.Initialize("VR")


End If

'loading the layout we use with the button on it.

Activity.LoadLayout("voice")

Activity.Color = Colors.Transparent 'Make the Activity transparent

If vr.IsSupported Then

ToastMessageShow("Voice recognition is supported.", False)

Else

ToastMessageShow("Voice recognition is not supported.", True)

End If

End Sub

Sub Button1_Click

vr.Listen 'calls the voice recognition external activity

End Sub


Sub Activity_Resume

End Sub


End Sub

In the next section I used message.Contains("reply") which meant that it parses the text

looking for the word reply. This can be used to detect accents as well. Read can be Reed,

or Red etc. Surprisingly it is Case Sensitive, and will not return if you make the words

capital case (well not for me anyway).

This system could be expanded for any number of keywords or phrases. Even to loading an

SMS with a nickname for a person “The Old Trout” for your Mother in law. Nicknames could

be kept in a database attached to the contacts list.

This part insult = Rnd(1,5) gives a random number between 1 and 5 not including 5.

Sub VR_Result (Success As Boolean, Texts As List)

If Success = True Then

ToastMessageShow(Texts.Get(0), True)

TTS1.Speak(Texts.Get(0), True)


message = Texts.Get(0)

'if the person says ... then

If message.Contains("reply") Then

smstextready

Else If message.Contains("read")OR message.Contains("reed") OR message.Contains("red")Then

readtext

Else

'random insult until they get it

insult = Rnd(1,5)

Select insult

Case 1

TTS1.Speak("Please speak clearer. Are you drunk?", True)

Case 2

TTS1.Speak("Don't take drugs and operate a phone. Try again", True)

Case 3

TTS1.Speak("Your breath smells of onions. Please move the phone away before trying again", True)


Case 4

TTS1.Speak("Please don't gargle and talk at the same time. Spit it out first then try again", True)

End Select

End If

End If

End Sub

In this section we get into the heart of the program. We load 2 text files, which we will have

to make later fromsms.txt and contactname.txt.

Note the If File.Exists(File.DirInternal, which is used to check that there is a file there to

start with. The first time its used there won’t be one and the program will crash, it’s a good

bit of protection.

The Dim i As Intent i.Initialize(i.ACTION_VIEW, "sms:" & number) is part for creating and

accessing an Intent, opening the SMS reply window which is another program. You use

Intents to open other programs on your phone. The action we are going to perform is VIEW

adding the number.

'OPEN THE REPLY WINDOW AND FILL THE NAME

Sub smstextready

Dim number, name As String

'get the smsnumber from the from file for the txtreply part of the program its the raw phone number

If File.Exists(File.DirInternal, "fromsms.txt")Then

number = File.ReadString(File.DirInternal, "fromsms.txt")

Else

number = File.ReadString(File.DirInternal, "from.txt")

End If

'get the name of the person to send it to and put it in the bar

If File.Exists(File.DirInternal, "contactname.txt")Then

name = File.ReadString(File.DirInternal, "contactname.txt")

Else 'you know you have a mistake when you want to call Howard

name = "Howard the Duck"

End If

Dim i As Intent

'set up the sms window with voodoo

i.Initialize(i.ACTION_VIEW, "sms:" & number)

'put the text into the body

TTS1.Speak("message ready", False)

i.PutExtra("sms_body", "")


'start it

StartActivity(i)

End Sub

'READ THE TEXT

Sub readtext



TTS1.Speak(message, False)

End Sub

Finally we need to create the text files. Back in your Service Module (SMS) Find the

following areas and add the code. We save to a text file to get it back later.

Add File.WriteString(File.DirInternal, "Fromsms.txt",From) here.

'The heart of the program

Sub SI_MessageReceived (From As String, Body As String) As Boolean

'Body and From are the two parts of the text message that are passed into the phone. write a file to open with the new text in txtreply on voice1

File.WriteString(File.DirInternal, "Fromsms.txt",From)

The contact name for the reply comes under the Sub SI_MessageReceived sub below If

From = phonenumber.


File.WriteString(File.DirInternal, "contactname.txt",Contact.Name)

Finally we need a way to start the Voice1 Activity. We are going to do that off the click on

the image the heart is StartActivity("voice1")

Sub ivimage_click

TTS1.speak("Press the Button. Then say Read or Reply", False)

StartActivity("voice1")

End Sub


16. Maps – Hashmap for Java, Hashtables for .net Map is a structure that is used frequently in Java. It’s listed as an advanced tool but it is very

versatile and useful.

A Map consists of two parts a KEY and a VALUE pair. The key is unique, while the value

can be anything. KEY VALUE are separated by a colon : If you enter a key/value pair and

the collection already holds an entry with the same key, the previous entry will be removed

from the map so it overwrites existing entries.

The idea is to look down the Key field for what you are seeking and take the data from the

value field. This is far faster than looping through all the entries in the ordinary way.

Fetching an item is done by looking for its key. This is usually a very fast operation (O(1)

compared to O(n) in a list).

The key could be a string or a number. The value can be any type of object. Eg:

Lists Phone numbers Date and Time

1:chocolate 2:apple 3:orange

345456:Susan 545678:Harvey 434565:Harold

21/2/12-10.32am:meeting 21/2/12-11.15am:Break 21/2/12-12.00pm:Lunch

Add data to your map with Put

Map1.Put("Key","Value")

Get keys and values back with Map.GetKeyAt(i)) and Map.GetValueAt(i)).and check if the

key exists then get it with If Map.ContainsKey("some key") Then ...

Data has to be looped in and out of a map.

For example

For i = 0 to Map.Size - 1 Log("Key: " & Map.GetKeyAt(i)) Log("Value: " & Map.GetValueAt(i)) Next

Or as we will do later insert the Map into other loops….

For x = 0 To phones.Size – 1

mastermapnames.Put(PhoneNum,Contact.DisplayName)

Next

You can have Maps of Maps and Lists of Maps.


Here is a good example of saving and retrieving data from two text boxes using a map.

17. Use Map to save multiple data to a single file Imagine you wanted to save all the text in a range of text boxes to a single file and then load

it back into the program later. It might be an edit option for long text entering, or an offline

option, or even to save a range of drafts. Its actually really easy to do with Maps

This very handy tool is easy to follow and uses PUT to save, and GET to retrieve.

The extra window shows the text file as saved and automatically saves with a data stamp.

This could create options for calling up versions.

Sub Globals

Dim map1 As Map

map1.Initialize

Dim btnsave As Button



Dim btnload As Button


End Sub



End Sub

Sub btnsave_Click

map1.Clear'clear the map, empty the data

'put the data in the map (KEY, VALUE)

map1.Put("EditText1", EditText1.Text)

map1.Put("EditText2", EditText2.Text)

File.WriteMap(File.DirInternal, "btnset.set", map1) 'write to file

EditText1.Text = ""'clear text boxes

EditText2.Text = ""

ToastMessageShow("data saved", False)

End Sub

Sub btnload_Click

'load back to map1 as a map (file.Readmap)

map1 = File.ReadMap(File.DirInternal, "btnset.set")

'show back in text boxes

EditText1.Text = map1.Get("EditText1")

EditText2.Text = map1.Get("EditText2")

ToastMessageShow("data loaded", False)

'show the datafile as saved for interest

EditText3.text = File.ReadString(File.DirInternal, "btnset.set")


End Sub

18. Project: Recipe selector using JSON Get an API from this site http://www.programmableweb.com/ to practise on and to see

what’s available.

JSON Overview

JSON (JavaScript Object Notation) is a lightweight data-interchange format. It is easy for

humans to read and write. It is easy for machines to parse and generate. It is a popular way

of transferring related data from internet databases to applications, and preferred by

Google. The ability to use JSON opens a vast area of data manipulation.

JSON is built on two structures:

A collection of name/value pairs. In various languages, this is realized as an object, a

map, struct, dictionary, hash table, keyed list, or associative array.

An ordered list of values. In most languages, this is realized as an array, vector, list,

or sequence.

An object is an unordered set of name/value pairs. An object begins with { (left brace) and

ends with } (right brace). Each name is followed by : (colon) and the name/value pairs are

separated by , (comma).

An array is an ordered collection of values. An array begins with [ (left bracket) and ends

with ] (right bracket). Values are separated by , (comma).

A value can be a string in double quotes, or a number, or true or false or null, or an object or

an array. These structures can be nested.

Here is a request to a server for some data that is returned in the JSON format.

http://www.recipepuppy.com/api/?i=onions,garlic&q=omelet&p=3

The data that is returned is in a string, to see the structure of it paste the link into

http://jsonformat.com/ and run.


http://www.recipepuppy.com/api/?i=onions,garlic&q=omelet&p=3

http://jsonformat.com/


A good overview can be found on the Wikipedia http://en.wikipedia.org/wiki/Json

The structure is nested. Here is the first set of data returned, with the end added on to make

it a single unit. Subsequent sets have the same structure.

{"title":"Recipe Puppy","version":0.1,

"href":"http:\/\/www.recipepuppy.com\/",

"results":

[{

"title":"Vegetable-Pasta Oven Omelet",

"href":"http:\/\/find.myrecipes.com\/recipes\/recipefinder.dyn?action=displayRecipe&recipe_id=520763",

"ingredients":"tomato, onions, red pepper, garlic, olive oil, zucchini, cream cheese, vermicelli, eggs, parmesan cheese, milk, italian seasoning, salt, black pepper",

"thumbnail":"http:\/\/img.recipepuppy.com\/560556.jpg"}, }

],}

This data looks confusing on the first look, and the second, and the …….

However look at the main text in terms of Maps. A Map is a Key:Value pair separated by a :

and this data is make up of maps with each map separated by a comma,

"title":"Vegetable-Pasta Oven Omelet"

It’s the format of Key:Value , Key:Value , Key:Value , Key:Value , Key:Value ,

This is an array of maps

The main part the data

"results":

[{

Is again Key:Value, the Key being Result, the Value being everything inside of the [{

The next page gives a better idea of the structure using a Firefox addon below. You can

clearly see the Blue Green matched Key Value pairs

http://en.wikipedia.org/wiki/Json


Recipe Program construction

This program requires us to access the net and download the JSON from the

http://www.recipepuppy.com website using their API (Application programming interface).

As a result we need the HTTP library.

We need”

1 panel

2 Buttons

3 Labels

2 edit boxes

1 imageview

Edtcode is only to see if the

code is coming down OK

LBLhyperlink and IVpic are

not set up so far, the pic will

go in the pic box and the

hyperlink will take you to the

website.

http://www.recipepuppy.com/


The code…

'Activity module

Sub Process_Globals

Dim hc As HttpClient 'download the json


Dim JSON As JSONParser

Dim Map1 As Map

End Sub

Sub Globals

Dim btnrun As Button

Dim datamap As Map

Dim btnnext As Button

Dim edtsearch, edtcode As EditText

Dim lblhyperlink,lblingredients, lbltitle As Label

Dim counter As Int :counter = 0

Dim ivpic As ImageView

Dim recipecode As String

End Sub



hc.Initialize("hc")

datamap.Initialize

'set as a default to save typing in all the time while testing

edtsearch.Text = "i=onions,garlic&q=omelet&p=3"

'initialise the JSON and tells it what it has to parse

JSON.Initialize(recipecode)

End Sub

Sub Activity_Resume

End Sub


End Sub

Sub btnrun_Click

Dim url, search As String

search = edtsearch.Text

url = "http://www.recipepuppy.com/api/?"& search

'i=onions,garlic&q=omelet&p=3"

'OPTIONS

'i=ingredients comma deliminated

'q=type of food eg omelet


'p= page number? -put page number in a counter so that it increments each time you press run? 1, 2, 3 – still to do

req.InitializeGet(url)

hc.Execute(req, 1)

ProgressDialogShow("downloading ...")

End Sub


Dim temp As String


recipecode = temp

edtcode.text = temp ‘Just to see what the code is on the screen

ProgressDialogHide

'run the download sub below (gets the first entry up and running)

download

counter = 0

End Sub

Totally standard error message copied from an earlier exercise




Response.Release

ProgressDialogHide


End If

End Sub

Sub btnnext_Click

download

End Sub

Sub download

JSON.Initialize(recipecode)

'JSON.NextObject parses the string and returns a Map with the parsed data. This method should be called when the top level value is an object (which is usually the case).

Map1 = JSON.NextObject

Dim results As List 'list holds all the recipes


results = Map1.Get("results")'top level with a key: the value is everything else in the code. key:value pass it to m

'Counter to move between recipes

counter = counter + 1

'If the counter reaches the last recipe then go back to the first one, otherwise crashes

If counter = results.Size Then

counter = 1

End If

'get the results at the place of the counter 1, 2, 3 etc

'some voodoo here

datamap = results.Get(counter)

lbltitle.Text = counter &" " & datamap.Get("title")

lblingredients.Text = datamap.Get("ingredients")

lblhyperlink.Text = datamap.Get("href") m

End Sub

Create your own APIS with http://apify.heroku.com/resources

How to make a hyperlink that opens the web browser

Creating a link to a local webbrowser is simple. In the code above we directly passed the

html to the text box, lblhyperlink.Text = datamap.Get("href") giving us a string of text that

sort of looks like an url.

'http:\/\/find.myrecipes.com\/recipes\/recipefinder.dyn?action=displayRecipe&recipe_id=520763",

To use this we need to remove the \\ symbols and turn it into an active URL.

The code for that is simple, create a new variable called hyperlink to hold the data and then

do a string replace to take out the unwanted symbols.

As I was feeling somewhat lazy I attached the url to the click event of the label box itself,

Sub lblhyperlink_Click it might go better under a button.

hyperlink = datamap.Get("href")

hyperlink = hyperlink.Replace("\","")

lblhyperlink.Text = hyperlink

End Sub

Sub lblhyperlink_Click

Dim p As PhoneIntents

StartActivity(p.OpenBrowser(hyperlink))

End Sub

This is no way the end of this program, only the beginning.

http://apify.heroku.com/resources

Visual Basic for Android June11

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Transcript of Visual Basic for Android June11