Canvas::Item Class Reference

An abstract item. More...

#include <canvas.h>

Inheritance diagram for Canvas::Item:

[legend]Collaboration diagram for Canvas::Item:

[legend]List of all members.

Public Member Functions
	Item (Abstract *canvas=NULL)
void	changed ()
bool	visible () const
void	setVisible (bool v)
bool	animated () const
void	setAnimated (bool a)
int	opacity () const
void	setOpacity (int o)
void	hide ()
void	show ()
void	raise ()
void	lower ()
void	stackOver (Item *ref)
void	stackUnder (Item *ref)
Abstract *	canvas () const
Widget *	topLevelCanvas () const
void	putInCanvas (Abstract *canvas)
QPoint	pos () const
void	moveTo (QPoint newpos)
void	moveTo (int x, int y)
virtual void	paint (QPainter *p)=0
virtual QRect	rect () const =0
virtual bool	layered () const
virtual void	advance (int msecs)
Friends
class	Abstract
class	Widget
class	Group

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Detailed Description

An abstract item.

A Item is an abstract class to represent a generic item that can be put in a canvas.

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Constructor & Destructor Documentation

Canvas::Item::Item (  Abstract *  canvas = NULL  )

Constructor, it allows you to specify the reference canvas or to create an orphan item that will be put into a canvas in a second moment. The item is always hidden after beeing created. Note that the restacking functions are quite intelligent and will only repaint if there is an actual need of doing it. So if you call raise on an item that is already (locally) on the top, no redraw will take place

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Member Function Documentation

void Canvas::Item::advance (  int  msecs  )  [virtual]

Override this function to handle animations, the default function does nothing. The argument is the number of milliseconds from the creation of the canvas, so that you use it to handle the animation. Reimplemented in Canvas::Group.

bool Canvas::Item::animated (   )  const [inline]

Returns true if the item is animated

Abstract* Canvas::Item::canvas (   )  const [inline]

Returns the canvas that is actually "owning" the item

void Canvas::Item::changed (   )  [inline]

schedule an update if the item

void Canvas::Item::hide (   )  [inline]

Hides the item

bool Canvas::Item::layered (   )  const [virtual]

Override this function to specify if the painting operations will paint over each other. If not, the item will be drawn more quickly when opacity is != 255, because it does not have to be painted onto a pixmap first. If you don't care about the item's opacity, don't care about this function as well.

void Canvas::Item::lower (   )

Restacks the item on the bottom of the canvas

void Canvas::Item::moveTo (  int  x, int  y )  [inline]

Overload, same as above

void Canvas::Item::moveTo (  QPoint  newpos  )

Sets a new position. Note that an update will be posted to the parent canvas, and if you move an item twice in very little time, a region bigger than needed will be updated, causing a possible inefficiency

int Canvas::Item::opacity (   )  const [inline]

Returns the opacity of the item

virtual void Canvas::Item::paint (  QPainter *  p  )  [pure virtual]

Override this function to draw the item with the painter Implemented in Canvas::Group, Canvas::Dummy, Canvas::Picture, Canvas::Pixmap, Canvas::TiledPixmap, Canvas::Rectangle, and Canvas::Text.

QPoint Canvas::Item::pos (   )  const [inline]

Returns the position of the item

void Canvas::Item::putInCanvas (  Abstract *  canvas  )

Lets you specify the owning canvas. Call this function with canvas set to NULL to remove the item from the current canvas.

void Canvas::Item::raise (   )

Restacks the item on the top of the canvas

virtual QRect Canvas::Item::rect (   )  const [pure virtual]

Override this function to return the rect the item will be drawn into Implemented in Canvas::Group, Canvas::Dummy, Canvas::Picture, Canvas::Pixmap, Canvas::TiledPixmap, Canvas::Rectangle, and Canvas::Text.

void Canvas::Item::setAnimated (  bool  a  )

Set the item as animated or not

void Canvas::Item::setOpacity (  int  o  )

Set the item's opacity value (int the 0-255 range)

void Canvas::Item::setVisible (  bool  v  )

Set the item as visible or hidden

void Canvas::Item::show (   )  [inline]

Shows the item

void Canvas::Item::stackOver (  Item *  ref  )

Restacks the item immediately over ref

void Canvas::Item::stackUnder (  Item *  ref  )

Restacks the item immediately under ref

Widget* Canvas::Item::topLevelCanvas (   )  const [inline]

Returns the toplevel canvas widget, or NULL

bool Canvas::Item::visible (   )  const [inline]

Returns true if the item is visible

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

• item.h
• canvas.cpp

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