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

#include <qwt_plot_barchart.h>

Inheritance diagram for QwtPlotBarChart:

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_PlotSVG, Rtti_PlotTradingCurve, Rtti_PlotBarChart, Rtti_PlotMultiBarChart, Rtti_PlotShape, Rtti_PlotTextLabel, Rtti_PlotZone, 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...

typedef QFlags< ItemAttribute >	ItemAttributes
	Plot Item Attributes.

typedef QFlags< ItemInterest >	ItemInterests
	Plot Item Interests.

typedef QFlags< RenderHint >	RenderHints
	Render hints.

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

	QwtPlotBarChart (const QwtText &title)

virtual	~QwtPlotBarChart ()
	Destructor.

virtual int	rtti () const

void	setSamples (const QVector< QPointF > &)

void	setSamples (const QVector< double > &)

void	setSamples (QwtSeriesData< QPointF > *series)

void	setSymbol (QwtColumnSymbol *)
	Assign a symbol. More...

const QwtColumnSymbol *	symbol () const

void	setLegendMode (LegendMode)

LegendMode	legendMode () const

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

virtual QRectF	boundingRect () const

virtual QwtColumnSymbol *	specialSymbol (int sampleIndex, const QPointF &) const

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

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

virtual	~QwtPlotAbstractBarChart ()
	Destructor.

void	setLayoutPolicy (LayoutPolicy)

LayoutPolicy	layoutPolicy () const

void	setLayoutHint (double)

double	layoutHint () const

void	setSpacing (int)
	Set the spacing. More...

int	spacing () const

void	setMargin (int)
	Set the margin. More...

int	margin () const

void	setBaseline (double)
	Set the baseline. More...

double	baseline () const

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

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

	QwtPlotSeriesItem (const QwtText &title)

virtual	~QwtPlotSeriesItem ()
	Destructor.

void	setOrientation (Qt::Orientation)

Qt::Orientation	orientation () const

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

virtual void	updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &)
	Update the item to changes of the axes scale division. More...

Public Member Functions inherited from QwtPlotItem
	QwtPlotItem (const QwtText &title=QwtText())

virtual	~QwtPlotItem ()
	Destroy the QwtPlotItem.

void	attach (QwtPlot *plot)
	Attach the item to a plot. More...

void	detach ()
	This method detaches a QwtPlotItem from any QwtPlot it has been associated with. More...

QwtPlot *	plot () const
	Return attached plot.

void	setTitle (const QString &title)

void	setTitle (const QwtText &title)

const QwtText &	title () const

void	setItemAttribute (ItemAttribute, bool on=true)

bool	testItemAttribute (ItemAttribute) const

void	setItemInterest (ItemInterest, bool on=true)

bool	testItemInterest (ItemInterest) const

void	setRenderHint (RenderHint, bool on=true)

bool	testRenderHint (RenderHint) const

void	setRenderThreadCount (uint numThreads)

uint	renderThreadCount () const

void	setLegendIconSize (const QSize &)

QSize	legendIconSize () const

double	z () const

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

void	show ()
	Show the item.

void	hide ()
	Hide the item.

virtual void	setVisible (bool)

bool	isVisible () const

void	setAxes (int xAxis, int yAxis)

void	setXAxis (int axis)

int	xAxis () const
	Return xAxis.

void	setYAxis (int axis)

int	yAxis () const
	Return yAxis.

virtual void	itemChanged ()

virtual void	legendChanged ()

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

QRectF	scaleRect (const QwtScaleMap &, const QwtScaleMap &) const
	Calculate the bounding scale rectangle of 2 maps. More...

QRectF	paintRect (const QwtScaleMap &, const QwtScaleMap &) const
	Calculate the bounding paint rectangle of 2 maps. More...

Public Member Functions inherited from QwtSeriesStore< QPointF >
	QwtSeriesStore ()
	Constructor The store contains no series.

	~QwtSeriesStore ()
	Destructor.

void	setData (QwtSeriesData< QPointF > *series)

QwtSeriesData< QPointF > *	data ()

const QwtSeriesData< QPointF > *	data () const

QPointF	sample (int index) const

virtual size_t	dataSize () const

virtual QRectF	dataRect () const

virtual void	setRectOfInterest (const QRectF &rect)

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

virtual void	drawBar (QPainter *, int sampleIndex, const QPointF &point, const QwtColumnRect &) const

QList< QwtLegendData >	legendData () const
	Return all information, that is needed to represent the item on the legend. More...

QwtGraphic	legendIcon (int index, const QSizeF &) const

Protected Member Functions inherited from QwtPlotAbstractBarChart
double	sampleWidth (const QwtScaleMap &map, double canvasSize, double dataSize, double value) const

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

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

Protected Member Functions inherited from QwtAbstractSeriesStore
virtual	~QwtAbstractSeriesStore ()
	Destructor.

Detailed Description

QwtPlotBarChart displays a series of a 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

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 ( const QString & title = QString::null )

explicit

Constructor

Parameters

title Title of the curve

QwtPlotBarChart::QwtPlotBarChart ( const QwtText & title )

explicit

Constructor

Parameters

title Title of the curve

Member Function Documentation

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

sampleIndex Index of the bar

Returns: An empty text

See Also: LegendBarTitles

QRectF QwtPlotBarChart::boundingRect ( ) const

virtual

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

Reimplemented from QwtPlotSeriesItem.

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

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()

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

virtual

Draw an interval of the bar chart

Parameters

painter	Painter
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
canvasRect	Contents rect of the canvas
from	Index of the first point to be painted
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.

QList< QwtLegendData > QwtPlotBarChart::legendData ( ) const

protectedvirtual

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.

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

protectedvirtual

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.

QwtPlotBarChart::LegendMode QwtPlotBarChart::legendMode ( ) const

Returns: Legend mode

See Also: setLegendMode()

int QwtPlotBarChart::rtti ( ) const

virtual

Returns: QwtPlotItem::Rtti_PlotBarChart

Reimplemented from QwtPlotItem.

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

mode New mode

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

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

Initialize data with an array of points

Parameters

samples Vector of points

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

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

samples Vector of y coordinates

Note: QVector is implicitly shared

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

data Data

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

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 delete by setting a new one. If symbol is NULL no symbol will be drawn.

Parameters

symbol Symbol

See Also: symbol()

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

virtual

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

Parameters

sampleIndex	Index of the sample represented by the bar
sample	Value of the sample

Returns: NULL, indicating to use the default symbol

const QwtColumnSymbol * QwtPlotBarChart::symbol ( ) const

Returns: Current symbol or NULL, when no symbol has been assigned

See Also: setSymbol()

Public Types

Public Member Functions

Protected Member Functions

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation