---

KPanelExtension Class Reference

KDE Panel Extension class. More...

#include <kpanelextension.h>

List of all members.

Public Types
enum	Type
	The type of the extention (TODO).
enum	Size
	Since: 3.1
Signals
void	updateLayout ()
Public Methods
	KPanelExtension (const QString &configFile, Type t=Normal, int actions=0, QWidget *parent=0, const char *name=0)
	~KPanelExtension ()
virtual QSize	sizeHint (Position, QSize maxsize) const
KConfig *	config () const
Type	type () const
int	actions () const
virtual void	action (Action a)
virtual Position	preferedPosition () const
Size	sizeSetting () const
int	customSize () const
Protected Methods
virtual void	about ()
virtual void	help ()
virtual void	preferences ()
virtual void	reportBug ()
Position	position () const
Alignment	alignment () const
Orientation	orientation ()
int	sizeInPixels () const
virtual void	positionChange (Position)
virtual void	alignmentChange (Alignment)

---

Detailed Description

KDE Panel Extension class.

Implements a panel extension.

Panel extensions

• Are small applications living in the Window Manager dock managed by the panel.
• Are implemented as DSOs (Dynamic Shared Objects).

Note: For security and stability reasons the panel won't load untrusted third party extensions directly into its namespace but via an external wrapper process.

The panel locates available extensions by searching for extension desktop files in (ALL_KDEDIRS)/share/apps/kicker/extensions. Every panel extension should install a desktop file there to be recognised by the panel.

Besides standard keys like "Name", "Comment" and "Icon" there are two panel extension specific keys:

@sect X-KDE-Library

Used by the panel to locate the extension DSO (Dynamic Shared Object) Example: X-KDE-Library=libexampleextension

@sect X-KDE-UniqueExtension

Similar to KApplication and KUniqueApplication there are two types of panel extensions. Use unique extensions when it makes no sence to run more than one instance of an extension in the panel. A good example for unique extensions is the taskbar extension. Use normal extensions when you need instance specific configuration. An example is a subpanel extension where you might want to run more than one instances. X-KDE-UniqueExtension is a boolean key which defaults to "false". Example: X-KDE-UniqueExtension=true

Back to panel extension DSOs, the following conventions are used for KDE: Name: lib<extensionname>extension.la LDFLAGS: -module -no-undefined

To implement a panel extension it is not enough to write a class inheriting from KPanelExtension but you also have to provide a factory function in your DSO. A sample factory function could look like this:

 extern "C"
 {
     KPanelExtension* init(QWidget *parent, const QString& configFile)
     {
         KGlobal::locale()->insertCatalogue("exampleextension");
         return new ExampleExtension(configFile, KPanelExtension::Normal,
                       KPanelExtension::About | KPanelExtension::Help | KPanelExtension::Preferences,
                       parent, "exampleextension");
     }
 }

 

Note: Don't change the factory function signature or the panel will fail to load your extension.

Author:

Matthias Elter <elter@kde.org>

Definition at line 96 of file kpanelextension.h.

---

Constructor & Destructor Documentation

KPanelExtension::KPanelExtension (  const QString &    configFile, Type    t = Normal, int    actions = 0, QWidget *    parent = 0, const char *    name = 0 )

Constructs a KPanelExtension just like any other widget. Parameters: configFile  The configFile handed over in the factory function. Type  The extension type(). actions  Standard RMB menu actions supported by the extension (see action() ). parent  The pointer to the parent widget handed over in the factory function. name  A Qt object name for your extension.

KPanelExtension::~KPanelExtension (    )

Destructor.

---

Member Function Documentation

virtual void KPanelExtension::about (    )  [inline, protected, virtual]

Is called when the user selects "About" from the extensions RMB menu. Reimplement this function to launch a about dialog. Note that this is called only when your extension supports the About action. See Action. Definition at line 226 of file kpanelextension.h.

virtual void KPanelExtension::action (  Action    a )  [virtual]

Generic action dispatcher. Called when the user selects an item from the extensions RMB menu. Reimplement this function to handle actions. For About, Help, Preferences and ReportBug use the convenience handlers ref about(), help(), preferences(), reportBug()

int KPanelExtension::actions (    )  const [inline]

Returns: int indicating the supported RMB menu actions. Action Definition at line 159 of file kpanelextension.h.

Alignment KPanelExtension::alignment (    )  const [inline, protected]

Returns: the extension's alignment. (left/top, center, or right/bottom) Definition at line 264 of file kpanelextension.h.

virtual void KPanelExtension::alignmentChange (  Alignment    )  [inline, protected, virtual]

This extension has changed its alignment. Reimplement this change handler in order to adjust the look of your applet. Definition at line 289 of file kpanelextension.h.

KConfig* KPanelExtension::config (    )  const [inline]

Always use this KConfig object to save/load your extensions configuration. For unique extensions this config object will write to a config file called <extensionname>rc in the users local KDE directory. For normal extensions this config object will write to a instance specific config file called <extensionname><instanceid>rc in the users local KDE directory. Definition at line 147 of file kpanelextension.h.

int KPanelExtension::customSize (    )

Returns: the custom sizel setting in pixels Since: 3.1

virtual void KPanelExtension::help (    )  [inline, protected, virtual]

Is called when the user selects "Help" from the extensions RMB menu. Reimplement this function to launch a manual or help page. Note that this is called only when your extension supports the Help action. See Action. Definition at line 235 of file kpanelextension.h.

Orientation KPanelExtension::orientation (    )  [protected]

Returns: the extensions orientation. (horizontal or vertical)

Position KPanelExtension::position (    )  const [inline, protected]

Returns: the extension's position. (left, right, top, bottom) Definition at line 259 of file kpanelextension.h.

virtual void KPanelExtension::positionChange (  Position    )  [inline, protected, virtual]

This extension has changed its position. Reimplement this change handler in order to adjust the look of your applet. Definition at line 282 of file kpanelextension.h.

virtual Position KPanelExtension::preferedPosition (    )  const [inline, virtual]

Reimplement this function to set a prefered dock position for your extension. The extension manager will try to place new instances of this extension according to this setting. Returns: Position Definition at line 180 of file kpanelextension.h.

virtual void KPanelExtension::preferences (    )  [inline, protected, virtual]

Is called when the user selects "Preferences" from the extensions RMB menu. Reimplement this function to launch a preferences dialog or kcontrol module. Note that this is called only when your extension supports the preferences action. See Action. Definition at line 244 of file kpanelextension.h.

virtual void KPanelExtension::reportBug (    )  [inline, protected, virtual]

Is called when the user selects "Report bug" from the applet's RMB menu. Reimplement this function to launch a bug reporting dialog. Note that this is called only when your applet supports the ReportBug action. See Action. Definition at line 254 of file kpanelextension.h.

virtual QSize KPanelExtension::sizeHint (  Position   , QSize    maxsize )  const [inline, virtual]

Returns the prefered size for a given Position. Every extension should reimplement this function. Depending on the panel position the extensions can choose a prefered size for that location in the Window Manager Dock. Please note that the size can not be larger than the maxsize given by the handler. Definition at line 136 of file kpanelextension.h.

int KPanelExtension::sizeInPixels (    )  [protected]

Returns: the appropriate size in pixels for the panel Since: 3.1

Size KPanelExtension::sizeSetting (    )

Returns: the extension's size Since: 3.1

Type KPanelExtension::type (    )  const [inline]

Returns: Type indicating the extensions type. Type Definition at line 153 of file kpanelextension.h. References Type.

void KPanelExtension::updateLayout (    )  [signal]

Emit this signal to make the panel relayout all extensions in the dock, when you want to change the extensions size. The panel is going to relayout all extensions based on their prefered size.

---

The documentation for this class was generated from the following file:

• kpanelextension.h

---