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VDKCanvas Class Reference

This class provides a canvas widget. More...

#include <canvas.h>

Inheritance diagram for VDKCanvas:

VDKObject VDKNotCopyAble VDKChart VDKBarChart VDKLineChart VDKScatteredChart List of all members.

Public Methods

Public Attributes


Detailed Description

This class provides a canvas widget.

Widget operation notes:
Drawing operation on canvas aren't done directly on the screen but using an offscreen backing pixmap. When necessary relevant portion of (or all) backing image is copied to screen.This makes drwaing muchfaster and avoids flickering. All user drawing operations should be followed by Draw() or Redraw() to effectively see the wanted effect. When applicable the best way is to connect with and write an expose-event response function where make all necessary drawing operations followed by a Redraw() call. See canvaswin.cc on ./testvdk directory for more detailed informations.
Tips:
By default canvas uses owner background and foreground, these can be set using properties.
Examples:
in ./testvdk/canvascompo.cc


Member Function Documentation

void VDKCanvas::Clear  
 

clears canvas area

Reimplemented in VDKChart.

void VDKCanvas::Redraw  
 

force a redrawing without expose_event

void VDKCanvas::SetBackground VDKRgb    color,
GtkStateType    state = GTK_STATE_NORMAL
[virtual]
 

Sets object background

Parameters:
color  a VDKRgb object
state  can be one of the gtk+ widget states

Reimplemented from VDKObject.

void VDKCanvas::SetFont VDKFont   f [virtual]
 

Sets object font

Reimplemented from VDKObject.

void VDKCanvas::SetForeground VDKRgb    color,
GtkStateType    state = GTK_STATE_NORMAL
[virtual]
 

Sets object foreground

Parameters:
color  a VDKRgb object
state  can be one of the gtk+ widget states

Reimplemented from VDKObject.


Member Data Documentation

VDKReadWriteValueProp<VDKCanvas,bool> VDKCanvas::EnableClear
 

default is true. It clears and refreshes the screen during the configure event. User can disable it to control the draw during the configure event


The documentation for this class was generated from the following files:
Generated on Wed Apr 17 13:24:56 2002 for vdk 2.0.1 by doxygen1.2.15