#include <qwt_plot.h>

Inherits QwtPlotDict.

Public Types
enum	Axis { yLeft, yRight, xBottom, xTop, axisCnt }
enum	LegendPosition { LeftLegend, RightLegend, BottomLegend, TopLegend, ExternalLegend }
Public Slots
void	autoRefresh ()
virtual void	replot ()
Signals
void	legendChecked (QwtPlotItem *plotItem, bool on)
void	legendClicked (QwtPlotItem *plotItem)
Public Member Functions
void	applyProperties (const QString &)
bool	autoDelete () const
bool	autoReplot () const
bool	axisAutoScale (int axisId) const
bool	axisEnabled (int axisId) const
QFont	axisFont (int axisId) const
QwtInterval	axisInterval (int axisId) const
int	axisMaxMajor (int axisId) const
int	axisMaxMinor (int axisId) const
const QwtScaleDiv *	axisScaleDiv (int axisId) const
QwtScaleDiv *	axisScaleDiv (int axisId)
const QwtScaleDraw *	axisScaleDraw (int axisId) const
QwtScaleDraw *	axisScaleDraw (int axisId)
QwtScaleEngine *	axisScaleEngine (int axisId)
const QwtScaleEngine *	axisScaleEngine (int axisId) const
double	axisStepSize (int axisId) const
QwtText	axisTitle (int axisId) const
const QwtScaleWidget *	axisWidget (int axisId) const
QwtScaleWidget *	axisWidget (int axisId)
QwtPlotCanvas *	canvas ()
const QwtPlotCanvas *	canvas () const
QBrush	canvasBackground () const
int	canvasLineWidth () const
virtual QwtScaleMap	canvasMap (int axisId) const
void	detachItems (int rtti=QwtPlotItem::Rtti_PlotItem, bool autoDelete=true)
virtual void	drawCanvas (QPainter *)
virtual void	drawItems (QPainter *, const QRectF &, const QwtScaleMap maps[axisCnt]) const
void	enableAxis (int axisId, bool tf=true)
virtual bool	event (QEvent *)
QString	grabProperties () const
void	insertLegend (QwtLegend *, LegendPosition=QwtPlot::RightLegend, double ratio=-1.0)
double	invTransform (int axisId, int pos) const
const QwtPlotItemList &	itemList () const
QwtPlotItemList	itemList (int rtti) const
QwtLegend *	legend ()
const QwtLegend *	legend () const
virtual QSize	minimumSizeHint () const
QwtPlotLayout *	plotLayout ()
const QwtPlotLayout *	plotLayout () const
	QwtPlot (QWidget *=NULL)
	QwtPlot (const QwtText &title, QWidget *p=NULL)
void	setAutoDelete (bool)
void	setAutoReplot (bool tf=true)
void	setAxisAutoScale (int axisId, bool on=true)
void	setAxisFont (int axisId, const QFont &f)
void	setAxisLabelAlignment (int axisId, Qt::Alignment)
void	setAxisLabelRotation (int axisId, double rotation)
void	setAxisMaxMajor (int axisId, int maxMajor)
void	setAxisMaxMinor (int axisId, int maxMinor)
void	setAxisScale (int axisId, double min, double max, double step=0)
void	setAxisScaleDiv (int axisId, const QwtScaleDiv &)
void	setAxisScaleDraw (int axisId, QwtScaleDraw *)
void	setAxisScaleEngine (int axisId, QwtScaleEngine *)
void	setAxisTitle (int axisId, const QString &)
void	setAxisTitle (int axisId, const QwtText &)
void	setCanvasBackground (const QBrush &)
void	setCanvasLineWidth (int w)
void	setTitle (const QString &)
void	setTitle (const QwtText &t)
virtual QSize	sizeHint () const
QwtText	title () const
QwtTextLabel *	titleLabel ()
const QwtTextLabel *	titleLabel () const
double	transform (int axisId, double value) const
void	updateAxes ()
virtual void	updateLayout ()
virtual	~QwtPlot ()
Protected Slots
virtual void	legendItemChecked (bool)
virtual void	legendItemClicked ()
Protected Member Functions
virtual void	resizeEvent (QResizeEvent *e)
virtual void	updateTabOrder ()
Static Protected Member Functions
static bool	axisValid (int axisId)

Detailed Description

A 2-D plotting widget.

QwtPlot is a widget for plotting two-dimensional graphs. An unlimited number of plot items can be displayed on its canvas. Plot items might be curves (QwtPlotCurve), markers (QwtPlotMarker), the grid (QwtPlotGrid), or anything else derived from QwtPlotItem. A plot can have up to four axes, with each plot item attached to an x- and a y axis. The scales at the axes can be explicitely set (QwtScaleDiv), or are calculated from the plot items, using algorithms (QwtScaleEngine) which can be configured separately for each axis.

Example

The following example shows (schematically) the most simple way to use QwtPlot. By default, only the left and bottom axes are visible and their scales are computed automatically.

#include <qwt_plot.h>
#include <qwt_plot_curve.h>

QwtPlot *myPlot = new QwtPlot("Two Curves", parent);

// add curves
QwtPlotCurve *curve1 = new QwtPlotCurve("Curve 1");
QwtPlotCurve *curve2 = new QwtPlotCurve("Curve 2");

// connect or copy the data to the curves
curve1->setData(...);
curve2->setData(...);

curve1->attach(myPlot);
curve2->attach(myPlot);

// finally, refresh the plot
myPlot->replot();

Member Enumeration Documentation

enum QwtPlot::Axis

Axis index.

Enumerator:

yLeft	Y axis left of the canvas.
yRight	Y axis right of the canvas.
xBottom	X axis below the canvas.
xTop	X axis above the canvas.
axisCnt	Number of axes.

enum QwtPlot::LegendPosition

Position of the legend, relative to the canvas.

See also:: insertLegend()

Note:: In case of ExternalLegend, the legend is not handled by QwtPlotRenderer

Enumerator:

LeftLegend	The legend will be left from the QwtPlot::yLeft axis.
RightLegend	The legend will be right from the QwtPlot::yRight axis.
BottomLegend	The legend will be below QwtPlot::xBottom axis.
TopLegend	The legend will be between QwtPlot::xTop axis and the title.
ExternalLegend	External means that only the content of the legend will be handled by QwtPlot, but not its geometry. This type can be used to have a legend in an external window ( or on the canvas ).

Constructor & Destructor Documentation

QwtPlot::QwtPlot ( QWidget * parent = NULL ) [explicit]

Constructor.

Parameters:

parent Parent widget

QwtPlot::QwtPlot	(	const QwtText &	title,
		QWidget *	parent = `NULL`
	)		`[explicit]`

Constructor.

Parameters:

title	Title text
parent	Parent widget

QwtPlot::~QwtPlot ( ) [virtual]

Destructor.

Member Function Documentation

void QwtPlot::applyProperties ( const QString & )

This method is intended for manipulating the plot widget from a specific editor in the Qwt designer plugin.

Warning:: The plot editor has never been implemented.

bool QwtPlotDict::autoDelete ( ) const [inherited]

Returns:: true if auto deletion is enabled

See also:: setAutoDelete(), attachItem()

void QwtPlot::autoRefresh ( ) [slot]

Replots the plot if autoReplot() is true.

bool QwtPlot::autoReplot ( ) const

Returns:: true if the autoReplot option is set.

See also:: setAutoReplot()

bool QwtPlot::axisAutoScale ( int axisId ) const

Returns:: true if autoscaling is enabled

Parameters:

axisId axis index

bool QwtPlot::axisEnabled ( int axisId ) const

Returns:: true if a specified axis is enabled

Parameters:

axisId axis index

QFont QwtPlot::axisFont ( int axisId ) const

Returns:: the font of the scale labels for a specified axis

Parameters:

axisId axis index

QwtInterval QwtPlot::axisInterval ( int axisId ) const

Return the current interval of the specified axis.

This is only a convenience function for axisScaleDiv( axisId )->interval();

Parameters:

axisId axis index

Returns:: Scale interval

See also:: QwtScaleDiv, axisScaleDiv()

int QwtPlot::axisMaxMajor ( int axisId ) const

Returns:: the maximum number of major ticks for a specified axis

Parameters:

axisId axis index

See also:: setAxisMaxMajor()

int QwtPlot::axisMaxMinor ( int axisId ) const

Returns:: the maximum number of minor ticks for a specified axis

Parameters:

axisId axis index

See also:: setAxisMaxMinor()

const QwtScaleDiv * QwtPlot::axisScaleDiv ( int axisId ) const

Return the scale division of a specified axis.

axisScaleDiv(axisId)->lowerBound(), axisScaleDiv(axisId)->upperBound() are the current limits of the axis scale.

Parameters:

axisId axis index

Returns:: Scale division

See also:: QwtScaleDiv, setAxisScaleDiv()

QwtScaleDiv * QwtPlot::axisScaleDiv ( int axisId )

Return the scale division of a specified axis.

axisScaleDiv(axisId)->lowerBound(), axisScaleDiv(axisId)->upperBound() are the current limits of the axis scale.

Parameters:

axisId axis index

Returns:: Scale division

See also:: QwtScaleDiv, setAxisScaleDiv()

const QwtScaleDraw * QwtPlot::axisScaleDraw ( int axisId ) const

Returns:: the scale draw of a specified axis

Parameters:

axisId axis index

Returns:: specified scaleDraw for axis, or NULL if axis is invalid.

See also:: QwtScaleDraw

QwtScaleDraw * QwtPlot::axisScaleDraw ( int axisId )

Returns:: the scale draw of a specified axis

Parameters:

axisId axis index

Returns:: specified scaleDraw for axis, or NULL if axis is invalid.

See also:: QwtScaleDraw

QwtScaleEngine * QwtPlot::axisScaleEngine ( int axisId )

Parameters:

axisId axis index

Returns:: Scale engine for a specific axis

const QwtScaleEngine * QwtPlot::axisScaleEngine ( int axisId ) const

Parameters:

axisId axis index

Returns:: Scale engine for a specific axis

double QwtPlot::axisStepSize ( int axisId ) const

Return the step size parameter, that has been set in setAxisScale. This doesn't need to be the step size of the current scale.

Parameters:

axisId axis index

Returns:: step size parameter value

See also:: setAxisScale()

QwtText QwtPlot::axisTitle ( int axisId ) const

Returns:: the title of a specified axis

Parameters:

axisId axis index

bool QwtPlot::axisValid ( int axisId ) [static, protected]

Returns:: true if the specified axis exists, otherwise false

Parameters:

axisId axis index

const QwtScaleWidget * QwtPlot::axisWidget ( int axisId ) const

Returns:: specified axis, or NULL if axisId is invalid.

Parameters:

axisId axis index

QwtScaleWidget * QwtPlot::axisWidget ( int axisId )

Returns:: specified axis, or NULL if axisId is invalid.

Parameters:

axisId axis index

QwtPlotCanvas * QwtPlot::canvas ( )

Returns:: the plot's canvas

const QwtPlotCanvas * QwtPlot::canvas ( ) const

Returns:: the plot's canvas

QBrush QwtPlot::canvasBackground ( ) const

Nothing else than: canvas()->palette().brush( QPalette::Normal, QPalette::Window);

Returns:: Background brush of the plotting area.

See also:: setCanvasBackground()

int QwtPlot::canvasLineWidth ( ) const

Nothing else than: canvas()->lineWidth(), left for compatibility only.

Returns:: the border width of the plotting area

QwtScaleMap QwtPlot::canvasMap ( int axisId ) const [virtual]

Parameters:

axisId Axis

Returns:: Map for the axis on the canvas. With this map pixel coordinates can translated to plot coordinates and vice versa.

See also:: QwtScaleMap, transform(), invTransform()

void QwtPlotDict::detachItems	(	int	rtti = `QwtPlotItem::Rtti_PlotItem`,
		bool	autoDelete = `true`
	)		`[inherited]`

Detach items from the dictionary

Parameters:

rtti	In case of QwtPlotItem::Rtti_PlotItem detach all items otherwise only those items of the type rtti.
autoDelete	If true, delete all detached items

void QwtPlot::drawCanvas ( QPainter * painter ) [virtual]

Redraw the canvas.

Parameters:

painter Painter used for drawing

Warning:: drawCanvas calls drawItems what is also used for printing. Applications that like to add individual plot items better overload drawItems()

See also:: drawItems()

void QwtPlot::drawItems	(	QPainter *	painter,
		const QRectF &	canvasRect,
		const QwtScaleMap	map[axisCnt]
	)		const `[virtual]`

Redraw the canvas items.

Parameters:

painter	Painter used for drawing
canvasRect	Bounding rectangle where to paint
map	QwtPlot::axisCnt maps, mapping between plot and paint device coordinates

void QwtPlot::enableAxis	(	int	axisId,
		bool	tf = `true`
	)

Enable or disable a specified axis.

When an axis is disabled, this only means that it is not visible on the screen. Curves, markers and can be attached to disabled axes, and transformation of screen coordinates into values works as normal.

Only xBottom and yLeft are enabled by default.

Parameters:

axisId	axis index
tf	`true` (enabled) or `false` (disabled)

bool QwtPlot::event ( QEvent * event ) [virtual]

Adds handling of layout requests.

Parameters:

event Event

QString QwtPlot::grabProperties ( ) const

This method is intended for manipulating the plot widget from a specific editor in the Qwt designer plugin.

Warning:: The plot editor has never been implemented.

void QwtPlot::insertLegend	(	QwtLegend *	legend,
		QwtPlot::LegendPosition	pos = `QwtPlot::RightLegend`,
		double	ratio = `-1.0`
	)

Insert a legend.

If the position legend is QwtPlot::LeftLegend or QwtPlot::RightLegend the legend will be organized in one column from top to down. Otherwise the legend items will be placed in a table with a best fit number of columns from left to right.

If pos != QwtPlot::ExternalLegend the plot widget will become parent of the legend. It will be deleted when the plot is deleted, or another legend is set with insertLegend().

Parameters:

legend	Legend
pos	The legend's position. For top/left position the number of colums will be limited to 1, otherwise it will be set to unlimited.
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:: legend(), QwtPlotLayout::legendPosition(), QwtPlotLayout::setLegendPosition()

double QwtPlot::invTransform	(	int	axisId,
		int	pos
	)		const

Transform the x or y coordinate of a position in the drawing region into a value.

Parameters:

axisId	axis index
pos	position

Warning:: The position can be an x or a y coordinate, depending on the specified axis.

const QwtPlotItemList & QwtPlotDict::itemList ( ) const [inherited]

A QwtPlotItemList of all attached plot items.

Use caution when iterating these lists, as removing/detaching an item will invalidate the iterator. Instead you can place pointers to objects to be removed in a removal list, and traverse that list later.

Returns:: List of all attached plot items.

QwtPlotItemList QwtPlotDict::itemList ( int rtti ) const [inherited]

Returns:: List of all attached plot items of a specific type.

See also:: QwtPlotItem::rtti()

QwtLegend * QwtPlot::legend ( )

Returns:: the plot's legend

See also:: insertLegend()

const QwtLegend * QwtPlot::legend ( ) const

Returns:: the plot's legend

See also:: insertLegend()

void QwtPlot::legendChecked	(	QwtPlotItem *	plotItem,
		bool	on
	)		`[signal]`

A signal which is emitted when the user has clicked on a legend item, which is in QwtLegend::CheckableItem mode

Parameters:

plotItem	Corresponding plot item of the selected legend item
on	True when the legen item is checked

Note:: clicks are disabled as default

See also:: QwtLegend::setItemMode(), QwtLegend::itemMode()

void QwtPlot::legendClicked ( QwtPlotItem * plotItem ) [signal]

A signal which is emitted when the user has clicked on a legend item, which is in QwtLegend::ClickableItem mode.

Parameters:

plotItem Corresponding plot item of the selected legend item

Note:: clicks are disabled as default

See also:: QwtLegend::setItemMode(), QwtLegend::itemMode()

void QwtPlot::legendItemChecked ( bool on ) [protected, virtual, slot]

Called internally when the legend has been checked Emits a legendClicked() signal.

void QwtPlot::legendItemClicked ( ) [protected, virtual, slot]

Called internally when the legend has been clicked on. Emits a legendClicked() signal.

QSize QwtPlot::minimumSizeHint ( ) const [virtual]

Return a minimum size hint.

QwtPlotLayout * QwtPlot::plotLayout ( )

Returns:: the plot's title

const QwtPlotLayout * QwtPlot::plotLayout ( ) const

Returns:: the plot's layout

void QwtPlot::replot ( ) [virtual, slot]

Redraw the plot.

If the autoReplot option is not set (which is the default) or if any curves are attached to raw data, the plot has to be refreshed explicitly in order to make changes visible.

See also:: setAutoReplot()

Warning:: Calls canvas()->repaint, take care of infinite recursions

void QwtPlot::resizeEvent ( QResizeEvent * e ) [protected, virtual]

Resize and update internal layout

Parameters:

e	Resize event

void QwtPlotDict::setAutoDelete ( bool autoDelete ) [inherited]

En/Disable Auto deletion

If Auto deletion is on all attached plot items will be deleted in the destructor of QwtPlotDict. The default value is on.

See also:: autoDelete(), attachItem()

void QwtPlot::setAutoReplot ( bool tf = true )

Set or reset the autoReplot option.

If the autoReplot option is set, the plot will be updated implicitly by manipulating member functions. Since this may be time-consuming, it is recommended to leave this option switched off and call replot() explicitly if necessary.

The autoReplot option is set to false by default, which means that the user has to call replot() in order to make changes visible.

Parameters:

tf	`true` or `false`. Defaults to `true`.

See also:: replot()

void QwtPlot::setAxisAutoScale	(	int	axisId,
		bool	on = `true`
	)

Enable autoscaling for a specified axis.

This member function is used to switch back to autoscaling mode after a fixed scale has been set. Autoscaling is enabled by default.

Parameters:

axisId	axis index
on	On/Off

See also:: setAxisScale(), setAxisScaleDiv(), updateAxes()

Note:: The autoscaling flag has no effect until updateAxes() is executed ( called by replot() ).

void QwtPlot::setAxisFont	(	int	axisId,
		const QFont &	f
	)

Change the font of an axis.

Parameters:

axisId	axis index
f	font

Warning:: This function changes the font of the tick labels, not of the axis title.

void QwtPlot::setAxisLabelAlignment	(	int	axisId,
		Qt::Alignment	alignment
	)

Change the alignment of the tick labels

Parameters:

axisId	axis index
alignment	Or'd Qt::AlignmentFlags see <qnamespace.h>

See also:: QwtScaleDraw::setLabelAlignment()

void QwtPlot::setAxisLabelRotation	(	int	axisId,
		double	rotation
	)

Rotate all tick labels

Parameters:

axisId	axis index
rotation	Angle in degrees. When changing the label rotation, the label alignment might be adjusted too.

See also:: QwtScaleDraw::setLabelRotation(), setAxisLabelAlignment()

void QwtPlot::setAxisMaxMajor	(	int	axisId,
		int	maxMajor
	)

Set the maximum number of major scale intervals for a specified axis

Parameters:

axisId	axis index
maxMajor	maximum number of major steps

See also:: axisMaxMajor()

void QwtPlot::setAxisMaxMinor	(	int	axisId,
		int	maxMinor
	)

Set the maximum number of minor scale intervals for a specified axis

Parameters:

axisId	axis index
maxMinor	maximum number of minor steps

See also:: axisMaxMinor()

void QwtPlot::setAxisScale	(	int	axisId,
		double	min,
		double	max,
		double	stepSize = `0`
	)

Disable autoscaling and specify a fixed scale for a selected axis.

Parameters:

axisId	axis index
min
max	minimum and maximum of the scale
stepSize	Major step size. If `step == 0`, the step size is calculated automatically using the maxMajor setting.

See also:: setAxisMaxMajor(), setAxisAutoScale(), axisStepSize()

void QwtPlot::setAxisScaleDiv	(	int	axisId,
		const QwtScaleDiv &	scaleDiv
	)

Disable autoscaling and specify a fixed scale for a selected axis.

Parameters:

axisId	axis index
scaleDiv	Scale division

See also:: setAxisScale(), setAxisAutoScale()

void QwtPlot::setAxisScaleDraw	(	int	axisId,
		QwtScaleDraw *	scaleDraw
	)

Set a scale draw.

Parameters:

axisId	axis index
scaleDraw	object responsible for drawing scales.

By passing scaleDraw it is possible to extend QwtScaleDraw functionality and let it take place in QwtPlot. Please note that scaleDraw has to be created with new and will be deleted by the corresponding QwtScale member ( like a child object ).

See also:: QwtScaleDraw, QwtScaleWidget

Warning:: The attributes of scaleDraw will be overwritten by those of the previous QwtScaleDraw.

void QwtPlot::setAxisScaleEngine	(	int	axisId,
		QwtScaleEngine *	scaleEngine
	)

Change the scale engine for an axis

Parameters:

axisId	axis index
scaleEngine	Scale engine

See also:: axisScaleEngine()

void QwtPlot::setAxisTitle	(	int	axisId,
		const QString &	title
	)

Change the title of a specified axis.

Parameters:

axisId	axis index
title	axis title

void QwtPlot::setAxisTitle	(	int	axisId,
		const QwtText &	title
	)

Change the title of a specified axis.

Parameters:

axisId	axis index
title	axis title

void QwtPlot::setCanvasBackground ( const QBrush & brush )

Change the background of the plotting area.

Sets brush to QPalette::Window of all colorgroups of the palette of the canvas. Using canvas()->setPalette() is a more powerful way to set these colors.

Parameters:

brush New background brush

See also:: canvasBackground()

void QwtPlot::setCanvasLineWidth ( int width )

Change the border width of the plotting area.

Nothing else than canvas()->setLineWidth(w), left for compatibility only.

Parameters:

width New border width

void QwtPlot::setTitle ( const QString & title )

Change the plot's title

Parameters:

title New title

void QwtPlot::setTitle ( const QwtText & title )

Change the plot's title

Parameters:

title New title

QSize QwtPlot::sizeHint ( ) const [virtual]

Return sizeHint

See also:: minimumSizeHint()

QwtText QwtPlot::title ( ) const

Returns:: Title of the plot

QwtTextLabel * QwtPlot::titleLabel ( )

Returns:: the plot's titel label.

const QwtTextLabel * QwtPlot::titleLabel ( ) const

Returns:: the plot's titel label.

double QwtPlot::transform	(	int	axisId,
		double	value
	)		const

Transform a value into a coordinate in the plotting region.

Parameters:

axisId	axis index
value	value

Returns:: X or y coordinate in the plotting region corresponding to the value.

void QwtPlot::updateAxes ( )

Rebuild the scales.

void QwtPlot::updateLayout ( ) [virtual]

Adjust plot content to its current size.

See also:: resizeEvent()

void QwtPlot::updateTabOrder ( ) [protected, virtual]

Update the focus tab order

The order is changed so that the canvas will be in front of the first legend item, or behind the last legend item - depending on the position of the legend.

Public Types

Public Slots

Signals

Public Member Functions

Protected Slots

Protected Member Functions

Static Protected Member Functions

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation