QwtPlotCanvas Class Reference

#include <qwt_plot_canvas.h>

List of all members.

Public Types
enum	FocusIndicator {   NoFocusIndicator,   CanvasFocusIndicator,   ItemFocusIndicator }
enum	PaintAttribute {   PaintCached = 1,   PaintPacked = 2 }

Public Member Functions
	QwtPlotCanvas (QwtPlot *)
virtual	~QwtPlotCanvas ()
FocusIndicator	focusIndicator () const
void	invalidatePaintCache ()
QPixmap *	paintCache ()
const QPixmap *	paintCache () const
QwtPlot *	plot ()
const QwtPlot *	plot () const
void	replot ()
void	setFocusIndicator (FocusIndicator)
void	setPaintAttribute (PaintAttribute, bool on=true)
bool	testPaintAttribute (PaintAttribute) const

Protected Member Functions
void	drawCanvas (QPainter *painter=NULL)
virtual void	drawContents (QPainter *)
virtual void	drawFocusIndicator (QPainter *)
virtual void	hideEvent (QHideEvent *)
virtual void	paintEvent (QPaintEvent *)

---

Detailed Description

Canvas of a QwtPlot.

See also:

QwtPlot

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Member Enumeration Documentation

enum QwtPlotCanvas::FocusIndicator

Focus indicator.

• NoFocusIndicator
  Don't paint a focus indicator

• CanvasFocusIndicator
  The focus is related to the complete canvas. Paint the focus indicator using paintFocus()

• ItemFocusIndicator
  The focus is related to an item (curve, point, ...) on the canvas. It is up to the application to display a focus indication using f.e. highlighting.

See also:

setFocusIndicator(), focusIndicator(), paintFocus()

enum QwtPlotCanvas::PaintAttribute

Paint attributes.

• PaintCached
  Paint double buffered and reuse the content of the pixmap buffer for some spontaneous repaints that happen when a plot gets unhidden, deiconified or changes the focus. Disabling the cache will improve the performance for incremental paints (using QwtPlotCurve::draw).

• PaintPacked
  Suppress system background repaints and paint it together with the canvas contents. Painting packed might avoid flickering for expensive repaints, when there is a notable gap between painting the background and the plot contents.

The default setting enables PaintCached and PaintPacked

See also:

setPaintAttribute(), testPaintAttribute(), paintCache()

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Member Function Documentation

void QwtPlotCanvas::drawCanvas ( QPainter *  painter = NULL )

protected

Draw the the canvas

Paints all plot items to the contentsRect(), using QwtPlot::drawCanvas and updates the paint cache.

Parameters:

painter

Painter

See also:

QwtPlot::drawCanvas(), setPaintAttributes(), testPaintAttributes()

void QwtPlotCanvas::drawContents ( QPainter *  painter )

protectedvirtual

Redraw the canvas, and focus rect

Parameters:

painter

Painter

void QwtPlotCanvas::drawFocusIndicator ( QPainter *  painter )

protectedvirtual

Draw the focus indication

Parameters:

painter

Painter

QwtPlotCanvas::FocusIndicator QwtPlotCanvas::focusIndicator

(

)

const

Returns:

Focus indicator

See also:

FocusIndicator, setFocusIndicator()

void QwtPlotCanvas::hideEvent ( QHideEvent *  event )

protectedvirtual

Hide event

Parameters:

event

Hide event

void QwtPlotCanvas::paintEvent ( QPaintEvent *  event )

protectedvirtual

Paint event

Parameters:

event

Paint event

void QwtPlotCanvas::replot

(

)

Invalidate the paint cache and repaint the canvas

See also:

invalidatePaintCache()

void QwtPlotCanvas::setFocusIndicator

(

FocusIndicator

focusIndicator

)

Set the focus indicator

See also:

FocusIndicator, focusIndicator()

void QwtPlotCanvas::setPaintAttribute	(	PaintAttribute	attribute,
		bool	on = true
	)

Changing the paint attributes.

Parameters:

attribute	Paint attribute
on	On/Off

The default setting enables PaintCached and PaintPacked

See also:

testPaintAttribute(), drawCanvas(), drawContents(), paintCache()

bool QwtPlotCanvas::testPaintAttribute

(

PaintAttribute

attribute

)

const

Test wether a paint attribute is enabled

Parameters:

attribute

Paint attribute

Returns:

true if the attribute is enabled

See also:

setPaintAttribute()