class KRootPixmap

Creates pseudo-transparent widgets. More...

Definition#include <krootpixmap.h>
InheritsQObject (qt) [public ]
List of all Methods
Annotated List
Files
Globals
Hierarchy
Index

Public Methods

Public Slots

Signals

Protected Methods


Detailed Description

Creates pseudo-transparent widgets.

A pseudo-transparent widget is a widget with its background pixmap set to that part of the desktop background that it is currently obscuring. This gives a transparency effect.

To create a transparent widget, construct a KRootPixmap and pass it a pointer to your widget. That's it! Moving, resizing and background changes are handled automatically.

Instead of using the default behaviour, you can ask KRootPixmap to emit a backgroundUpdated(const QPixmap &) signal whenever the background needs updating by using setCustomPainting(bool). Alternatively by reimplementing updateBackground(KSharedPixmap*) you can take complete control of the behaviour.

 KRootPixmap ( QWidget *target, const char *name=0 )

KRootPixmap

Constructs a KRootPixmap. The KRootPixmap will be created as a child of the target widget so it will be deleted automatically when the widget is destroyed.

Parameters:
targetA pointer to the widget that you want to make pseudo transparent.

 KRootPixmap ( QWidget *target, QObject *parent, const char *name=0 )

KRootPixmap

Constructs a KRootPixmap where the parent QObject and target QWidget are different.

 ~KRootPixmap ()

~KRootPixmap

[virtual]

Destructs the object.

bool  isAvailable ()

isAvailable

[const]

Checks if pseudo-transparency is available.

Returns: true if transparency is available, false otherwise.

bool  isActive ()

isActive

[const]

Returns true if the KRootPixmap is active.

int  currentDesktop ()

currentDesktop

[const]

Returns the number of the current desktop.

bool  customPainting ()

customPainting

[const]

Returns true if custom painting is enabled, false otherwise.

See also: setCustomPainting(bool)

bool  checkAvailable (bool)

checkAvailable

Deprecated, use isAvailable() instead.

void  start ()

start

[virtual slot]

Starts background handling.

void  stop ()

stop

[virtual slot]

Stops background handling.

void  setFadeEffect (double strength, const QColor &color)

setFadeEffect

[slot]

Sets the fade effect.

This effect will fade the background to the specified color.

Parameters:
strengthA value between 0 and 1, indicating the strength of the fade. A value of 0 will not change the image, a value of 1 will make it the fade color everywhere, and in between.
colorThe color to fade to.

void  repaint ( bool force )

repaint

[slot]

Repaints the widget background. Normally, you shouldn't need this as it is handled automatically.

Parameters:
forceForce a repaint, even if the contents did not change.

void  repaint ()

repaint

[slot]

Repaints the widget background. Normally, you shouldn't need this as it is handled automatically. This is equivalent to calling repaint( false ).

void  setCustomPainting ( bool enable )

setCustomPainting

[slot]

Enables custom handling of the background painting. If custom painting is enabled then KRootPixmap will emit a backgroundUpdated() signal when the background for the target widget changes, instead of applying the new background.

void  enableExports ()

enableExports

[slot]

Asks KDesktop to export the desktop background as a KSharedPixmap. This method uses DCOP to call KBackgroundIface/setExport(int).

void  backgroundUpdated ( const QPixmap &pm )

backgroundUpdated

[signal]

Emitted when the background needs updating and custom painting (see setCustomPainting(bool) ) is enabled.

Parameters:
pmA pixmap containing the new background.

bool  eventFilter (QObject *, QEvent *)

eventFilter

[protected virtual]

Reimplemented to filter the events from the target widget and track its movements.

void  updateBackground ( KSharedPixmap * )

updateBackground

[protected virtual]

Called when the pixmap has been updated. The default implementation applies the fade effect, then sets the target's background, or emits backgroundUpdated(const QPixmap &) depending on the painting mode.