QwtPlotBarChart displays a series of values as bars. More...

#include <qwt_plot_barchart.h>

Inheritance diagram for QwtPlotBarChart:

Classes
class	PrivateData

Public Types
enum	LegendMode { LegendChartTitle , LegendBarTitles }
	Legend modes. More...

Public Types inherited from QwtPlotAbstractBarChart
enum	LayoutPolicy { AutoAdjustSamples , ScaleSamplesToAxes , ScaleSampleToCanvas , FixedSampleSize }
	Mode how to calculate the bar width. More...

Public Types inherited from QwtPlotItem
enum	RttiValues { Rtti_PlotItem = 0 , Rtti_PlotGrid , Rtti_PlotScale , Rtti_PlotLegend , Rtti_PlotMarker , Rtti_PlotCurve , Rtti_PlotSpectroCurve , Rtti_PlotIntervalCurve , Rtti_PlotHistogram , Rtti_PlotSpectrogram , Rtti_PlotGraphic , Rtti_PlotTradingCurve , Rtti_PlotBarChart , Rtti_PlotMultiBarChart , Rtti_PlotShape , Rtti_PlotTextLabel , Rtti_PlotZone , Rtti_PlotVectorField , Rtti_PlotArrowMarker , Rtti_PlotBoxChart , Rtti_PlotUserItem = 1000 }
	Runtime type information. More...

enum	ItemAttribute { Legend = 0x01 , AutoScale = 0x02 , Margins = 0x04 }
	Plot Item Attributes. More...

enum	ItemInterest { ScaleInterest = 0x01 , LegendInterest = 0x02 }
	Plot Item Interests. More...

enum	RenderHint { RenderAntialiased = 0x1 }
	Render hints. More...

Public Member Functions
	QwtPlotBarChart (const QString &title=QString())

	QwtPlotBarChart (const QwtText &title)
	Constructor.

virtual int	rtti () const override
	Get the runtime type information.

void	attach (QwtPlot *plot) override
	Attach the bar chart to a plot.

void	setSamples (const QVector< QPointF > &)
	Initialize data with an array of points.

void	setSamples (const QVector< double > &)
	Initialize data with an array of doubles.

void	setSamples (QwtSeriesData< QPointF > *)
	Assign a series of samples.

void	setSymbol (QwtColumnSymbol *)
	Assign a symbol.

const QwtColumnSymbol *	symbol () const
	Get the current symbol.

void	setPen (const QPen &p)
	Set the bar symbol pen.

QPen	pen () const
	Get the bar symbol pen.

void	setBrush (const QBrush &b)
	Set the bar symbol brush.

QBrush	brush () const
	Get the bar symbol brush.

void	setFrameStyle (QwtColumnSymbol::FrameStyle f)
	Set the bar symbol frame style.

QwtColumnSymbol::FrameStyle	frameStyle () const
	Get the bar symbol frame style.

void	setLegendMode (LegendMode)
	Set the mode that decides what to display on the legend.

LegendMode	legendMode () const
	Get the legend mode.

virtual void	drawSeries (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const override
	Draw an interval of the bar chart.

virtual QRectF	boundingRect () const override
	Get the bounding rectangle of all samples.

virtual QwtColumnSymbol *	specialSymbol (int sampleIndex, const QPointF &) const
	Get a special symbol for a specific sample.

virtual QwtText	barTitle (int sampleIndex) const
	Return the title of a bar.

Public Member Functions inherited from QwtPlotAbstractBarChart
	QwtPlotAbstractBarChart (const QwtText &title)
	Constructor.

void	setLayoutPolicy (LayoutPolicy)
	Set the layout policy.

LayoutPolicy	layoutPolicy () const
	Get the layout policy.

void	setLayoutHint (double)
	Set the layout hint.

double	layoutHint () const
	Get the layout hint.

void	setSpacing (int)
	Set the spacing between bars.

int	spacing () const
	Get the spacing between bars.

void	setMargin (int)
	Set the margin around the bars.

int	margin () const
	Get the margin around the bars.

void	setBaseline (double)
	Set the baseline value.

double	baseline () const
	Get the baseline value.

virtual void	getCanvasMarginHint (const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, double &left, double &top, double &right, double &bottom) const override
	Calculate a hint for the canvas margin.

Public Member Functions inherited from QwtPlotSeriesItem
	QwtPlotSeriesItem (const QString &title=QString())

	QwtPlotSeriesItem (const QwtText &title)
	Constructor.

void	setOrientation (Qt::Orientation)
	Set the orientation of the item.

Qt::Orientation	orientation () const
	Get the orientation of the plot item.

virtual void	draw (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect) const override
	Draw the complete series.

virtual void	updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &) override
	Update the scale divisions.

Public Member Functions inherited from QwtPlotItem
	QwtPlotItem ()
	Default constructor.

	QwtPlotItem (const QString &title)
	Constructor with title as QString.

	QwtPlotItem (const QwtText &title)
	Constructor with title as QwtText.

virtual	~QwtPlotItem ()
	Destructor.

void	detach ()
	Detach the item from the plot.

QwtPlot *	plot () const
	Get the plot the item is attached to.

void	setTitle (const QString &title)
	Set the title using a QString.

void	setTitle (const QwtText &title)
	Set the title using a QwtText.

const QwtText &	title () const
	Get the title.

void	setItemAttribute (ItemAttribute, bool on=true)
	Set an item attribute.

bool	testItemAttribute (ItemAttribute) const
	Test an item attribute.

void	setItemInterest (ItemInterest, bool on=true)
	Set an item interest.

bool	testItemInterest (ItemInterest) const
	Test an item interest.

void	setRenderHint (RenderHint, bool on=true)
	Set a render hint.

bool	testRenderHint (RenderHint) const
	Test a render hint.

void	setRenderThreadCount (uint numThreads)
	Set the number of render threads.

uint	renderThreadCount () const
	Get the number of render threads.

void	setLegendIconSize (const QSize &)
	Set the legend icon size.

QSize	legendIconSize () const
	Get the legend icon size.

double	z () const
	Get the z-value.

void	setZ (double z)
	Set the z-value.

void	show ()
	Show the item.

void	hide ()
	Hide the item.

virtual void	setVisible (bool)
	Set the visibility.

bool	isVisible () const
	Check if the item is visible.

void	setAxes (QwtAxisId xAxis, QwtAxisId yAxis)
	Set both axes.

void	setXAxis (QwtAxisId)
	Set the x-axis.

QwtAxisId	xAxis () const
	Get the x-axis.

void	setYAxis (QwtAxisId)
	Set the y-axis.

QwtAxisId	yAxis () const
	Get the y-axis.

virtual void	itemChanged ()
	Notify the plot that the item has changed.

virtual void	legendChanged ()
	Notify the item that the legend has changed.

virtual void	updateLegend (const QwtPlotItem *, const QList< QwtLegendData > &)
	Update the item with changes of the legend.

QRectF	scaleRect (const QwtScaleMap &, const QwtScaleMap &) const
	Calculate the scale rectangle.

QRectF	paintRect (const QwtScaleMap &, const QwtScaleMap &) const
	Calculate the paint rectangle.

Public Member Functions inherited from QwtSeriesStore< QPointF >
void	setData (QwtSeriesData< QPointF > *series)

QwtSeriesData< QPointF > *	data ()

const QwtSeriesData< QPointF > *	data () const

QPointF	sample (size_t index) const

virtual size_t	dataSize () const override

virtual QRectF	dataRect () const override

virtual void	setRectOfInterest (const QRectF &rect) override
	Set a the "rectangle of interest" for the stored series.

QwtSeriesData< QPointF > *	swapData (QwtSeriesData< QPointF > *series)

Protected Member Functions
virtual void	drawSample (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, const QwtInterval &boundingInterval, int index, const QPointF &sample) const
	Draw a sample.

virtual void	drawBar (QPainter *, int sampleIndex, const QPointF &sample, const QwtColumnRect &) const
	Draw a bar.

QwtColumnRect	columnRect (const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, const QwtInterval &boundingInterval, const QPointF &sample) const
	Get column rectangle.

QList< QwtLegendData >	legendData () const override
	Get legend data.

QwtGraphic	legendIcon (int index, const QSizeF &) const override
	Get legend icon.

Protected Member Functions inherited from QwtPlotAbstractBarChart
double	sampleWidth (const QwtScaleMap &map, double canvasSize, double boundingSize, double value) const
	Calculate the width for a sample in paint device coordinates.

Protected Member Functions inherited from QwtPlotSeriesItem
virtual void	dataChanged () override
	dataChanged() indicates, that the series has been changed.

Protected Member Functions inherited from QwtPlotItem
QwtGraphic	defaultIcon (const QBrush &, const QSizeF &) const
	Create a default icon.

Detailed Description

QwtPlotBarChart displays a series of values as bars.

Each bar might be customized individually by implementing a specialSymbol(). Otherwise it is rendered using a default symbol.

Depending on its orientation() the bars are displayed horizontally or vertically. The bars cover the interval between the baseline() and the value.

By activating the LegendBarTitles mode each sample will have its own entry on the legend.

The most common use case of a bar chart is to display a list of y coordinates, where the x coordinate is simply the index in the list. But for other situations ( f.e. when values are related to dates ) it is also possible to set x coordinates explicitly.

See also: QwtPlotMultiBarChart, QwtPlotHistogram, QwtPlotCurve::Sticks, QwtPlotSeriesItem::orientation(), QwtPlotAbstractBarChart::baseline()

Member Enumeration Documentation

◆ LegendMode

enum QwtPlotBarChart::LegendMode

Legend modes.

The default setting is QwtPlotBarChart::LegendChartTitle.

See also: setLegendMode(), legendMode()

Enumerator

LegendChartTitle

One entry on the legend showing the default symbol and the title() of the chart

See also: QwtPlotItem::title()

LegendBarTitles

One entry for each value showing the individual symbol of the corresponding bar and the bar title.

See also: specialSymbol(), barTitle()

Constructor & Destructor Documentation

◆ QwtPlotBarChart()

QwtPlotBarChart::QwtPlotBarChart ( const QwtText & title )

explicit

Constructor.

Parameters

[in] title Title of the chart

Constructor

Parameters

[in] title Title of the chart

Destructor

Member Function Documentation

◆ attach()

void QwtPlotBarChart::attach ( QwtPlot * plot )

overridevirtual

Attach the bar chart to a plot.

If the brush has not been explicitly set by the user, the bar chart automatically receives a color from the plot's color cycle. The pen is set to a darker shade of the fill color unless user-set.

Parameters

plot	Plot to attach to (nullptr to detach)

Reimplemented from QwtPlotItem.

◆ barTitle()

QwtText QwtPlotBarChart::barTitle ( int sampleIndex ) const

virtual

Return the title of a bar.

In LegendBarTitles mode the title is displayed on the legend entry corresponding to a bar. The default implementation is a dummy, that is intended to be overloaded.

Parameters

[in] sampleIndex Index of the bar

Returns: An empty text

See also: LegendBarTitles

◆ boundingRect()

QRectF QwtPlotBarChart::boundingRect ( ) const

overridevirtual

Get the bounding rectangle of all samples.

Returns: Bounding rectangle of all samples. For an empty series the rectangle is invalid.

Reimplemented from QwtPlotSeriesItem.

◆ brush()

QBrush QwtPlotBarChart::brush ( ) const

Get the bar symbol brush.

Returns: Brush for filling the bar

◆ columnRect()

QwtColumnRect QwtPlotBarChart::columnRect	(	const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		const QwtInterval &	boundingInterval,
		const QPointF &	sample
	)		const

protected

Get column rectangle.

Calculate the geometry of a bar in widget coordinates.

Parameters

xMap	x map
yMap	y map
canvasRect	Contents rect of the canvas
boundingInterval	Bounding interval of sample values
sample	Value of the sample

Returns: Geometry of the column

◆ drawBar()

void QwtPlotBarChart::drawBar	(	QPainter *	painter,
		int	sampleIndex,
		const QPointF &	sample,
		const QwtColumnRect &	rect
	)		const

protectedvirtual

Draw a bar.

Parameters

painter	Painter
sampleIndex	Index of the sample represented by the bar
sample	Value of the sample
rect	Bounding rectangle of the bar

◆ drawSample()

void QwtPlotBarChart::drawSample	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		const QwtInterval &	boundingInterval,
		int	index,
		const QPointF &	sample
	)		const

protectedvirtual

Draw a sample.

Parameters

painter	Painter
xMap	x map
yMap	y map
canvasRect	Contents rect of the canvas
boundingInterval	Bounding interval of sample values
index	Index of the sample
sample	Value of the sample

See also: drawSeries()

◆ drawSeries()

void QwtPlotBarChart::drawSeries	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to
	)		const

overridevirtual

Draw an interval of the bar chart.

Parameters

[in]	painter	Painter
[in]	xMap	Maps x-values into pixel coordinates.
[in]	yMap	Maps y-values into pixel coordinates.
[in]	canvasRect	Contents rect of the canvas
[in]	from	Index of the first point to be painted
[in]	to	Index of the last point to be painted. If to < 0 the curve will be painted to its last point.

See also: drawSymbols()

Implements QwtPlotSeriesItem.

◆ frameStyle()

QwtColumnSymbol::FrameStyle QwtPlotBarChart::frameStyle ( ) const

Get the bar symbol frame style.

Returns: Frame style for the bar

◆ legendData()

QList< QwtLegendData > QwtPlotBarChart::legendData ( ) const

overrideprotectedvirtual

Get legend data.

Return all information, that is needed to represent the item on the legend.

In case of LegendBarTitles an entry for each bar is returned, otherwise the chart is represented like any other plot item from its title() and the legendIcon().

Returns: Information, that is needed to represent the item on the legend

See also: title(), setLegendMode(), barTitle(), QwtLegend, QwtPlotLegendItem

Reimplemented from QwtPlotItem.

◆ legendIcon()

QwtGraphic QwtPlotBarChart::legendIcon	(	int	index,
		const QSizeF &	size
	)		const

overrideprotectedvirtual

Get legend icon.

Returns: Icon representing a bar or the chart on the legend

When the legendMode() is LegendBarTitles the icon shows the bar corresponding to index - otherwise the bar displays the default symbol.

Parameters

index	Index of the legend entry
size	Icon size

See also: setLegendMode(), drawBar(), QwtPlotItem::setLegendIconSize(), QwtPlotItem::legendData()

Reimplemented from QwtPlotItem.

◆ legendMode()

QwtPlotBarChart::LegendMode QwtPlotBarChart::legendMode ( ) const

Get the legend mode.

Returns: Legend mode

See also: setLegendMode()

◆ pen()

QPen QwtPlotBarChart::pen ( ) const

Get the bar symbol pen.

Returns: Pen for drawing the bar outline

◆ rtti()

int QwtPlotBarChart::rtti ( ) const

overridevirtual

Get the runtime type information.

Returns: QwtPlotItem::Rtti_PlotBarChart

Reimplemented from QwtPlotItem.

◆ setBrush()

void QwtPlotBarChart::setBrush ( const QBrush & b )

Set the bar symbol brush.

Parameters

[in] b Brush for filling the bar

◆ setFrameStyle()

void QwtPlotBarChart::setFrameStyle ( QwtColumnSymbol::FrameStyle f )

Set the bar symbol frame style.

Parameters

[in] f Frame style for the bar

◆ setLegendMode()

void QwtPlotBarChart::setLegendMode ( LegendMode mode )

Set the mode that decides what to display on the legend.

In case of LegendBarTitles barTitle() needs to be overloaded to return individual titles for each bar.

Parameters

[in] mode New mode

See also: legendMode(), legendData(), barTitle(), QwtPlotItem::ItemAttribute

◆ setPen()

void QwtPlotBarChart::setPen ( const QPen & p )

Set the bar symbol pen.

Parameters

[in] p Pen for drawing the bar outline

◆ setSamples() [1/3]

void QwtPlotBarChart::setSamples ( const QVector< double > & samples )

Initialize data with an array of doubles.

The indices in the array are taken as x coordinate, while the doubles are interpreted as y values.

Parameters

[in] samples Vector of y coordinates

Note: QVector is implicitly shared.

◆ setSamples() [2/3]

void QwtPlotBarChart::setSamples ( const QVector< QPointF > & samples )

Initialize data with an array of points.

Parameters

[in] samples Vector of points

Note: QVector is implicitly shared.; QPolygonF is derived from QVector<QPointF>.

◆ setSamples() [3/3]

void QwtPlotBarChart::setSamples ( QwtSeriesData< QPointF > * data )

Assign a series of samples.

setSamples() is just a wrapper for setData() without any additional value - beside that it is easier to find for the developer.

Parameters

[in] data Data

Warning: The item takes ownership of the data object, deleting it when its not used anymore.

◆ setSymbol()

void QwtPlotBarChart::setSymbol ( QwtColumnSymbol * symbol )

Assign a symbol.

The bar chart will take the ownership of the symbol, hence the previously set symbol will be deleted by setting a new one. If symbol is nullptr no symbol will be drawn.

Parameters

[in] symbol Symbol

See also: symbol()

◆ specialSymbol()

QwtColumnSymbol * QwtPlotBarChart::specialSymbol	(	int	sampleIndex,
		const QPointF &	sample
	)		const

virtual

Get a special symbol for a specific sample.

Needs to be overloaded to return a non default symbol for a specific sample.

Parameters

[in]	sampleIndex	Index of the sample represented by the bar
[in]	sample	Value of the sample

Returns: nullptr, indicating to use the default symbol

◆ symbol()

const QwtColumnSymbol * QwtPlotBarChart::symbol ( ) const

Get the current symbol.

Returns: Current symbol or nullptr, when no symbol has been assigned.

See also: setSymbol()

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

/home/runner/work/QWT/QWT/src/plot/qwt_plot_barchart.h
/home/runner/work/QWT/QWT/src/plot/qwt_plot_barchart.cpp

Classes

Public Types

Public Member Functions

Protected Member Functions

Detailed Description

Member Enumeration Documentation

◆ LegendMode

Constructor & Destructor Documentation

◆ QwtPlotBarChart()

Member Function Documentation

◆ attach()

◆ barTitle()

◆ boundingRect()

◆ brush()

◆ columnRect()

◆ drawBar()

◆ drawSample()

◆ drawSeries()

◆ frameStyle()

◆ legendData()

◆ legendIcon()

◆ legendMode()

◆ pen()

◆ rtti()

◆ setBrush()

◆ setFrameStyle()

◆ setLegendMode()

◆ setPen()

◆ setSamples() [1/3]

◆ setSamples() [2/3]

◆ setSamples() [3/3]

◆ setSymbol()

◆ specialSymbol()

◆ symbol()