KRootPixmap Class Reference

#include <krootpixmap.h>

Inherits TQObject.

Public Slots
virtual void	start ()
virtual void	stop ()
void	setFadeEffect (double opacity, const TQColor &color)
void	setBlurEffect (double radius, double sigma)
void	repaint (bool force)
void	repaint ()
void	setCustomPainting (bool enable)
void	enableExports ()
static TQString	pixmapName (int desk)

Signals
void	backgroundUpdated (const TQPixmap &pm)

Public Member Functions
	KRootPixmap (TQWidget *target, const char *name=0)
	KRootPixmap (TQWidget *target, TQObject *parent, const char *name=0)
virtual	~KRootPixmap ()
bool	isAvailable () const
bool	isActive () const
int	currentDesktop () const
bool	customPainting () const
TDE_DEPRECATED bool	checkAvailable (bool)
const TQColor &	color () const
const double &	blurRadius () const
const double &	blurSigma () const
double	opacity () const

Protected Member Functions
virtual bool	eventFilter (TQObject *, TQEvent *)
virtual void	updateBackground (TDESharedPixmap *)

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

Author

Geert Jansen janse.nosp@m.n@kd.nosp@m.e.org

Version

$Id$

Definition at line 46 of file krootpixmap.h.

Constructor & Destructor Documentation

KRootPixmap() [1/2]

KRootPixmap::KRootPixmap	(	TQWidget *	target,
		const char *	name = 0
	)

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

target	A pointer to the widget that you want to make pseudo transparent.
name	The internal name of the pixmap

Definition at line 46 of file krootpixmap.cpp.

KRootPixmap() [2/2]

KRootPixmap::KRootPixmap	(	TQWidget *	target,
		TQObject *	parent,
		const char *	name = 0
	)

Constructs a KRootPixmap where the parent TQObject and target TQWidget are different.

Definition at line 52 of file krootpixmap.cpp.

~KRootPixmap()

KRootPixmap::~KRootPixmap ( )

virtual

Destructs the object.

Definition at line 85 of file krootpixmap.cpp.

Member Function Documentation

backgroundUpdated

void KRootPixmap::backgroundUpdated ( const TQPixmap &  pm )

signal

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

Parameters

pm	A pixmap containing the new background.

blurRadius()

const double& KRootPixmap::blurRadius ( ) const

inline

Since

3.5

Returns

the blur radius.

Definition at line 111 of file krootpixmap.h.

blurSigma()

const double& KRootPixmap::blurSigma ( ) const

inline

Since

3.5

Returns

the blur sigma.

Definition at line 116 of file krootpixmap.h.

checkAvailable()

TDE_DEPRECATED bool KRootPixmap::checkAvailable ( bool  )

inline

Deprecated, use isAvailable() instead.

Deprecated:

Definition at line 100 of file krootpixmap.h.

color()

const TQColor& KRootPixmap::color ( ) const

inline

Since

3.2

Returns

the fade color.

Definition at line 106 of file krootpixmap.h.

currentDesktop()

int KRootPixmap::currentDesktop

(

)

const

Returns the number of the current desktop.

Definition at line 92 of file krootpixmap.cpp.

customPainting()

bool KRootPixmap::customPainting ( ) const

inline

Returns true if custom painting is enabled, false otherwise.

See also

setCustomPainting(bool)

Definition at line 93 of file krootpixmap.h.

enableExports

void KRootPixmap::enableExports ( )

slot

Asks KDesktop to export the desktop background as a TDESharedPixmap.

This method uses DCOP to call KBackgroundIface/setExport(int).

Definition at line 276 of file krootpixmap.cpp.

eventFilter()

bool KRootPixmap::eventFilter ( TQObject *  , TQEvent *  event  )

protectedvirtual

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

Definition at line 148 of file krootpixmap.cpp.

isActive()

bool KRootPixmap::isActive ( ) const

inline

Returns true if the KRootPixmap is active.

Definition at line 82 of file krootpixmap.h.

isAvailable()

bool KRootPixmap::isAvailable

(

)

const

Checks if pseudo-transparency is available.

Returns

true if transparency is available, false otherwise.

Definition at line 255 of file krootpixmap.cpp.

opacity()

double KRootPixmap::opacity ( ) const

inline

Since

3.2

Returns

the color opacity.

Definition at line 121 of file krootpixmap.h.

pixmapName

TQString KRootPixmap::pixmapName ( int  desk )

staticslot

Returns the name of the shared pixmap (only needed for low level access)

Definition at line 264 of file krootpixmap.cpp.

repaint [1/2]

void KRootPixmap::repaint ( )

slot

Repaints the widget background.

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

Definition at line 209 of file krootpixmap.cpp.

repaint [2/2]

void KRootPixmap::repaint ( bool  force )

slot

Repaints the widget background.

Normally, you shouldn't need this as it is handled automatically.

Parameters

force

Force a repaint, even if the contents did not change.

Definition at line 215 of file krootpixmap.cpp.

setBlurEffect

void KRootPixmap::setBlurEffect ( double  radius, double  sigma  )

slot

Sets the blue effect.

This effect will blur the background with the specified values. If both values are set to zero no blur is applied (this is the default).

Parameters

radius	The radius of the gaussian not counting the center pixel. Use 0 and a suitable radius will be automatically used.
sigma	The standard deviation of the gaussian. Use 1 if you're not sure.

Definition at line 142 of file krootpixmap.cpp.

setCustomPainting

void KRootPixmap::setCustomPainting ( bool  enable )

inlineslot

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.

Definition at line 179 of file krootpixmap.h.

setFadeEffect

void KRootPixmap::setFadeEffect ( double  opacity, const TQColor &  color  )

slot

Sets the fade effect.

This effect will fade the background to the specified color.

Parameters

opacity	A value between 0 and 1, indicating the opacity of the color. A value of 0 will not change the image, a value of 1 will use the fade color unchanged.
color	The color to fade to.

Definition at line 129 of file krootpixmap.cpp.

start

void KRootPixmap::start ( )

virtualslot

Starts background handling.

Definition at line 105 of file krootpixmap.cpp.

stop

void KRootPixmap::stop ( )

virtualslot

Stops background handling.

Definition at line 122 of file krootpixmap.cpp.

updateBackground()

void KRootPixmap::updateBackground ( TDESharedPixmap *  spm )

protectedvirtual

Called when the pixmap has been updated.

The default implementation applies the fade effect, then sets the target's background, or emits backgroundUpdated(const TQPixmap &) depending on the painting mode.

Definition at line 311 of file krootpixmap.cpp.

---

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

• krootpixmap.h
• krootpixmap.cpp