Hildon Desktop Widgets by Dimitry Pastushenko

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Hildon Desktop Widgets

Dmitry Pastushenko


Agenda

•Hildon Desktop Home Widgets

•Widget Packaging

•Widget Declaration and Definition

•Widget API

•Hands-on

•Summary


Hildon Desktop Widgets

4 Desktops, 3200x424 pixels total space


Example Widget

•Calculates random numbers in 0-1000 range every second

•Changes color of generated number every 1/3 of a second

•Implements settings dialog

•Preserves battery life


Widget Debian

Package

•

Shared Library•

/usr/lib/hildon-desktop/libwidgetexample.so

•

Desktop File•

/usr/share/applications/hildon-home/widget-example.desktop

•

Data (Resources)•

/usr/share/…


Desktop file (widget-example.desktop)

[Desktop Entry]

Name=Widget Example

Comment=Widget Example

Type=default

X-Path=libwidgetexample.so

X-Multiple-Instances=false


WidgetExample

Dependency


GObject

Library

•

Cornerstone of GNOME and is used throughout GTK+, Pango, and most higher-level GNOME libraries

•

Provides transparent cross-language interoperability

•

Provides a portable object system


WidgetExample

Class Diagram


Widget Declaration, Part 1typedef

struct

_WidgetExample

WidgetExample;typedef

struct

_WidgetExampleClass

WidgetExampleClass;typedef

struct

_WidgetExamplePrivate

WidgetExamplePrivate;

struct

_WidgetExample

{ /* instance */ HDHomePluginItem

item; /* superclass

instance */WidgetExamplePrivate

*priv; /* private data */};

struct

_WidgetExampleClass

{ /* class */HDHomePluginItemClass

parent_class; /* superclass

*/};

GType

widget_example_get_type

(void);


Widget Declaration, Part 2#define TYPE_WIDGET_EXAMPLE (widget_example_get_type

())#define WIDGET_EXAMPLE(obj) \(G_TYPE_CHECK_INSTANCE_CAST ((obj), TYPE_WIDGET_EXAMPLE, WidgetExample))

#define WIDGET_EXAMPLE_CLASS(klass) \(G_TYPE_CHECK_CLASS_CAST ((klass), TYPE_WIDGET_EXAMPLE, WidgetExampleClass))

#define IS_WIDGET_EXAMPLE(obj) \( G_TYPE_CHECK_INSTANCE_TYPE ((obj), TYPE_WIDGET_EXAMPLE) )

#define IS_WIDGET_EXAMPLE_CLASS(klass) \( G_TYPE_CHECK_CLASS_TYPE ((klass), TYPE_WIDGET_EXAMPLE) )

#define WIDGET_EXAMPLE_GET_CLASS(obj) \( G_TYPE_INSTANCE_GET_CLASS ((obj), TYPE_WIDGET_EXAMPLE, WidgetExampleClass) )

#define WIDGET_EXAMPLE_GET_PRIVATE(obj) \( G_TYPE_INSTANCE_GET_PRIVATE (obj, TYPE_WIDGET_EXAMPLE, WidgetExamplePrivate) )


Widget Definition & Mandatory Methods•

HD_DEFINE_PLUGIN_MODULE (WidgetExample, widget_example, \HD_TYPE_HOME_PLUGIN_ITEM);

•

static void widget_example_class_init

(WidgetExampleClass

*class)•

Object Initialization –

override GObject::dispose, GtkWindow::realize, GtkWindow::expose_event

•

Register private data

•

static void widget_example_class_finalize

(WidgetExampleClass

*class) •

Object Destruction

•

static void widget_example_init

(WidgetExample

* applet) •

Initialize all public and private members of instance to default

values•

Create UI•

Subscribe on signals


Call Flow


Summary•

Follow Nokia’s UI guideline•

Should provide most crucial features•

Use semitransparent background, if applicable•

Events should be initiated on release•

Never exceed half of desktop space

•

Preserve battery life•

On current display signal •

Device inactivity state signal

•

Applet is a plug-in -

don’t forget to yield

•

Threads are allowed, but drawing should be done from main loop


Q&A

Hildon Desktop Widgets by Dimitry Pastushenko

Technology

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