Qwt User's Guide: QwtPlotLayout Class Reference

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QwtPlotLayout Class Reference

#include <qwt_plot_layout.h>

Public Types
enum	Options { AlignScales = 1, IgnoreScrollbars = 2, IgnoreFrames = 4, IgnoreMargin = 8, IgnoreLegend = 16 }
Public Member Functions
	QwtPlotLayout ()
virtual	~QwtPlotLayout ()
void	setMargin (int)
int	margin () const
void	setCanvasMargin (int margin, int axis=-1)
int	canvasMargin (int axis) const
void	setAlignCanvasToScales (bool)
bool	alignCanvasToScales () const
void	setSpacing (int)
int	spacing () const
void	setLegendPosition (QwtPlot::LegendPosition pos, double ratio)
void	setLegendPosition (QwtPlot::LegendPosition pos)
QwtPlot::LegendPosition	legendPosition () const
void	setLegendRatio (double ratio)
double	legendRatio () const
virtual QSize	minimumSizeHint (const QwtPlot *) const
virtual void	activate (const QwtPlot *, const QRect &rect, int options=0)
virtual void	invalidate ()
const QRect &	titleRect () const
const QRect &	legendRect () const
const QRect &	scaleRect (int axis) const
const QRect &	canvasRect () const
Protected Member Functions
QRect	layoutLegend (int options, const QRect &) const
QRect	alignLegend (const QRect &canvasRect, const QRect &legendRect) const
void	expandLineBreaks (int options, const QRect &rect, int &dimTitle, int dimAxes[QwtPlot::axisCnt]) const
void	alignScales (int options, QRect &canvasRect, QRect scaleRect[QwtPlot::axisCnt]) const

Detailed Description

Layout engine for QwtPlot.

It is used by the QwtPlot widget to organize its internal widgets or by QwtPlot::print() to render its content to a QPaintDevice like a QPrinter, QPixmap/QImage or QSvgRenderer.

Member Enumeration Documentation

enum QwtPlotLayout::Options

Options to configure the plot layout engine

AlignScales
Unused
IgnoreScrollbars
Ignore the dimension of the scrollbars. There are no scrollbars, when the plot is rendered to a paint device (QwtPlot::print() ).
IgnoreFrames
Ignore all frames. QwtPlot::print() doesn't paint them.
IgnoreMargin
Ignore the margin().
IgnoreLegend
Ignore the legend.

See also:: activate()

Constructor & Destructor Documentation

QwtPlotLayout::QwtPlotLayout ( ) [explicit]

Constructor.

QwtPlotLayout::~QwtPlotLayout ( ) [virtual]

Destructor.

Member Function Documentation

void QwtPlotLayout::activate	(	const QwtPlot *	plot,
		const QRect &	plotRect,
		int	options = `0`
	)			`[virtual]`

Recalculate the geometry of all components.

Parameters:

	plot	Plot to be layout
	plotRect	Rect where to place the components
	options	Options

See also:: invalidate(), Options, titleRect(), legendRect(), scaleRect(), canvasRect()

bool QwtPlotLayout::alignCanvasToScales ( ) const

Return the align-canvas-to-axis-scales setting. The canvas may:

extend beyond the axis scale ends to maximize its size
align with the axis scale ends to control its size.

Returns:: align-canvas-to-axis-scales setting

See also:: setAlignCanvasToScales, setCanvasMargin()

Note:: In this context the term 'scale' means the backbone of a scale.

QRect QwtPlotLayout::alignLegend	(	const QRect &	canvasRect,
		const QRect &	legendRect
	)			const `[protected]`

Align the legend to the canvas

Parameters:

	canvasRect	Geometry of the canvas
	legendRect	Maximum geometry for the legend

Returns:: Geometry for the aligned legend

void QwtPlotLayout::alignScales	(	int	options,
		QRect &	canvasRect,
		QRect	scaleRect[QwtPlot::axisCnt]
	)			const `[protected]`

Align the ticks of the axis to the canvas borders using the empty corners.

See also:: Options

int QwtPlotLayout::canvasMargin ( int axis ) const

Returns:: Margin around the scale tick borders

See also:: setCanvasMargin()

const QRect & QwtPlotLayout::canvasRect ( ) const

Returns:: Geometry for the canvas

See also:: activate(), invalidate()

void QwtPlotLayout::expandLineBreaks	(	int	options,
		const QRect &	rect,
		int &	dimTitle,
		int	dimAxis[QwtPlot::axisCnt]
	)			const `[protected]`

Expand all line breaks in text labels, and calculate the height of their widgets in orientation of the text.

Parameters:

	options	Options how to layout the legend
	rect	Bounding rect for title, axes and canvas.
	dimTitle	Expanded height of the title widget
	dimAxis	Expanded heights of the axis in axis orientation.

See also:: Options

void QwtPlotLayout::invalidate ( ) [virtual]

Invalidate the geometry of all components.

See also:: activate()

QRect QwtPlotLayout::layoutLegend	(	int	options,
		const QRect &	rect
	)			const `[protected]`

Find the geometry for the legend

Parameters:

	options	Options how to layout the legend
	rect	Rectangle where to place the legend

Returns:: Geometry for the legend

See also:: Options

QwtPlot::LegendPosition QwtPlotLayout::legendPosition ( ) const

Returns:: Position of the legend

See also:: setLegendPosition(), QwtPlot::setLegendPosition(), QwtPlot::legendPosition()

double QwtPlotLayout::legendRatio ( ) const

Returns:: The relative size of the legend in the plot.

See also:: setLegendPosition()

const QRect & QwtPlotLayout::legendRect ( ) const

Returns:: Geometry for the legend

See also:: activate(), invalidate()

int QwtPlotLayout::margin ( ) const

Returns:: margin

See also:: setMargin(), spacing(), QwtPlot::margin()

QSize QwtPlotLayout::minimumSizeHint ( const QwtPlot * plot ) const [virtual]

Return a minimum size hint.

See also:: QwtPlot::minimumSizeHint()

const QRect & QwtPlotLayout::scaleRect ( int axis ) const

Parameters:

axis

Axis index

Returns:: Geometry for the scale

See also:: activate(), invalidate()

void QwtPlotLayout::setAlignCanvasToScales ( bool alignCanvasToScales )

Change the align-canvas-to-axis-scales setting. The canvas may:

extend beyond the axis scale ends to maximize its size,
align with the axis scale ends to control its size.

Parameters:

alignCanvasToScales

New align-canvas-to-axis-scales setting

See also:: setCanvasMargin()

Note:: In this context the term 'scale' means the backbone of a scale.

Warning:: In case of alignCanvasToScales == true canvasMargin will have no effect

void QwtPlotLayout::setCanvasMargin	(	int	margin,
		int	axis = `-1`
	)

Change a margin of the canvas. The margin is the space above/below the scale ticks. A negative margin will be set to -1, excluding the borders of the scales.

Parameters:

	margin	New margin
	axis	One of QwtPlot::Axis. Specifies where the position of the margin. -1 means margin at all borders.

See also:: canvasMargin()

Warning:: The margin will have no effect when alignCanvasToScales is true

void QwtPlotLayout::setLegendPosition ( QwtPlot::LegendPosition pos )

Specify the position of the legend.

Parameters:

pos The legend's position. Valid values are QwtPlot::LeftLegend, QwtPlot::RightLegend, QwtPlot::TopLegend, QwtPlot::BottomLegend.

See also:: QwtPlot::setLegendPosition()

void QwtPlotLayout::setLegendPosition	(	QwtPlot::LegendPosition	pos,
		double	ratio
	)

Specify the position of the legend.

Parameters:

	pos	The legend's position.
	ratio	Ratio between legend and the bounding rect of title, canvas and axes. The legend will be shrinked if it would need more space than the given ratio. The ratio is limited to ]0.0 .. 1.0]. In case of <= 0.0 it will be reset to the default ratio. The default vertical/horizontal ratio is 0.33/0.5.

See also:: QwtPlot::setLegendPosition()

void QwtPlotLayout::setLegendRatio ( double ratio )

Specify the relative size of the legend in the plot

Parameters:

ratio

Ratio between legend and the bounding rect of title, canvas and axes. The legend will be shrinked if it would need more space than the given ratio. The ratio is limited to ]0.0 .. 1.0]. In case of <= 0.0 it will be reset to the default ratio. The default vertical/horizontal ratio is 0.33/0.5.

void QwtPlotLayout::setMargin ( int margin )

Change the margin of the plot. The margin is the space around all components.

Parameters:

margin

new margin