QChart Class

The QChart class manages the graphical representation of the chart's series, legends, and axes. More...

Header:	#include <QChart>
Inherits:	QGraphicsWidget
Inherited By:	QPolarChart

• List of all members, including inherited members
• Obsolete members

Public Types

enum	AnimationOption { NoAnimation, GridAxisAnimations, SeriesAnimations, AllAnimations }
flags	AnimationOptions
enum	ChartTheme { ChartThemeLight, ChartThemeBlueCerulean, ChartThemeDark, ChartThemeBrownSand, ChartThemeBlueNcs, …, ChartThemeQt }
enum	ChartType { ChartTypeUndefined, ChartTypeCartesian, ChartTypePolar }

Properties

animationDuration : int animationEasingCurve : QEasingCurve animationOptions : QChart::AnimationOptions backgroundRoundness : qreal backgroundVisible : bool chartType : const QChart::ChartType dropShadowEnabled : bool

locale : QLocale localizeNumbers : bool margins : QMargins plotArea : QRectF plotAreaBackgroundVisible : bool theme : QChart::ChartTheme title : QString

Public Functions

	QChart(QGraphicsItem *parent = nullptr, Qt::WindowFlags wFlags = Qt::WindowFlags())
virtual	~QChart()
void	addAxis(QAbstractAxis *axis, Qt::Alignment alignment)
void	addSeries(QAbstractSeries *series)
int	animationDuration() const
QEasingCurve	animationEasingCurve() const
QChart::AnimationOptions	animationOptions() const
QList<QAbstractAxis *>	axes(Qt::Orientations orientation = Qt::Horizontal|Qt::Vertical, QAbstractSeries *series = nullptr) const
QBrush	backgroundBrush() const
QPen	backgroundPen() const
qreal	backgroundRoundness() const
QChart::ChartType	chartType() const
void	createDefaultAxes()
bool	isBackgroundVisible() const
bool	isDropShadowEnabled() const
bool	isPlotAreaBackgroundVisible() const
bool	isZoomed()
QLegend *	legend() const
QLocale	locale() const
bool	localizeNumbers() const
QPointF	mapToPosition(const QPointF &value, QAbstractSeries *series = nullptr)
QPointF	mapToValue(const QPointF &position, QAbstractSeries *series = nullptr)
QMargins	margins() const
QRectF	plotArea() const
QBrush	plotAreaBackgroundBrush() const
QPen	plotAreaBackgroundPen() const
void	removeAllSeries()
void	removeAxis(QAbstractAxis *axis)
void	removeSeries(QAbstractSeries *series)
void	scroll(qreal dx, qreal dy)
QList<QAbstractSeries *>	series() const
void	setAnimationDuration(int msecs)
void	setAnimationEasingCurve(const QEasingCurve &curve)
void	setAnimationOptions(QChart::AnimationOptions options)
void	setBackgroundBrush(const QBrush &brush)
void	setBackgroundPen(const QPen &pen)
void	setBackgroundRoundness(qreal diameter)
void	setBackgroundVisible(bool visible = true)
void	setDropShadowEnabled(bool enabled = true)
void	setLocale(const QLocale &locale)
void	setLocalizeNumbers(bool localize)
void	setMargins(const QMargins &margins)
void	setPlotArea(const QRectF &rect)
void	setPlotAreaBackgroundBrush(const QBrush &brush)
void	setPlotAreaBackgroundPen(const QPen &pen)
void	setPlotAreaBackgroundVisible(bool visible = true)
void	setTheme(QChart::ChartTheme theme)
void	setTitle(const QString &title)
void	setTitleBrush(const QBrush &brush)
void	setTitleFont(const QFont &font)
QChart::ChartTheme	theme() const
QString	title() const
QBrush	titleBrush() const
QFont	titleFont() const
void	zoom(qreal factor)
void	zoomIn()
void	zoomIn(const QRectF &rect)
void	zoomOut()
void	zoomReset()

Signals

void	plotAreaChanged(const QRectF &plotArea)

Detailed Description

QChart is a QGraphicsWidget that you can show in a QGraphicsScene. It manages the graphical representation of different types of series and other chart related objects like legend and axes. To simply show a chart in a layout, the convenience class QChartView can be used instead of QChart. In addition, line, spline, area, and scatter series can be presented as polar charts by using the QPolarChart class.

See also QChartView and QPolarChart.

Member Type Documentation

enum QChart::AnimationOptionflags QChart::AnimationOptions

This enum describes the animations enabled in the chart.

Constant	Value	Description
QChart::NoAnimation	0x0	Animation is disabled in the chart. This is the default value.
QChart::GridAxisAnimations	0x1	Grid axis animation is enabled in the chart.
QChart::SeriesAnimations	0x2	Series animation is enabled in the chart.
QChart::AllAnimations	0x3	All animation types are enabled in the chart.

The AnimationOptions type is a typedef for QFlags<AnimationOption>. It stores an OR combination of AnimationOption values.

enum QChart::ChartTheme

This enum describes the theme used by the chart.

A theme is a built-in collection of UI style related settings applied to all the visual elements of a chart, such as colors, pens, brushes, and fonts of series, as well as axes, title, and legend. The Chart themes example illustrates how to use themes.

Note: Changing the theme will overwrite all customizations previously applied to the series.

Constant	Value	Description
QChart::ChartThemeLight	0	The light theme, which is the default theme.
QChart::ChartThemeBlueCerulean	1	The cerulean blue theme.
QChart::ChartThemeDark	2	The dark theme.
QChart::ChartThemeBrownSand	3	The sand brown theme.
QChart::ChartThemeBlueNcs	4	The natural color system (NCS) blue theme.
QChart::ChartThemeHighContrast	5	The high contrast theme.
QChart::ChartThemeBlueIcy	6	The icy blue theme.
QChart::ChartThemeQt	7	The Qt theme.

enum QChart::ChartType

This enum describes the chart type.

Constant	Value	Description
QChart::ChartTypeUndefined	0	The chart type is not defined.
QChart::ChartTypeCartesian	1	A cartesian chart.
QChart::ChartTypePolar	2	A polar chart.

Member Function Documentation

QChart::QChart(QGraphicsItem *parent = nullptr, Qt::WindowFlags wFlags = Qt::WindowFlags())

Constructs a chart object that is a child of parent. The properties specified by wFlags are passed to the QGraphicsWidget constructor.

[virtual] QChart::~QChart()

Deletes the chart object and its children, such as the series and axis objects added to it.

void QChart::addAxis(QAbstractAxis *axis, Qt::Alignment alignment)

Adds the axis axis to the chart aligned as specified by alignment. The chart takes the ownership of the axis.

See also removeAxis(), createDefaultAxes(), and QAbstractSeries::attachAxis().

void QChart::addSeries(QAbstractSeries *series)

Adds the series series to the chart and takes ownership of it.

Note: A newly added series is not attached to any axes by default, not even those that might have been created for the chart using createDefaultAxes() before the series was added to the chart. If no axes are attached to the newly added series before the chart is shown, the series will get drawn as if it had axes with ranges that exactly fit the series to the plot area of the chart. This can be confusing if the same chart also displays other series that have properly attached axes, so always make sure you either call createDefaultAxes() after a series has been added or explicitly attach axes for the series.

See also removeSeries(), removeAllSeries(), createDefaultAxes(), and QAbstractSeries::attachAxis().

QList<QAbstractAxis *> QChart::axes(Qt::Orientations orientation = Qt::Horizontal|Qt::Vertical, QAbstractSeries *series = nullptr) const

Returns the axes attached to the series series with the orientation specified by orientation. If no series is specified, all axes added to the chart with the specified orientation are returned.

See also addAxis() and createDefaultAxes().

QBrush QChart::backgroundBrush() const

Gets the brush that is used for painting the background of the chart area.

See also setBackgroundBrush().

QPen QChart::backgroundPen() const

Gets the pen that is used for painting the background of the chart area.

See also setBackgroundPen().

void QChart::createDefaultAxes()

Creates axes for the chart based on the series that have already been added to the chart. Any axes previously added to the chart will be deleted.

Note: This function has to be called after all series have been added to the chart. The axes created by this function will NOT get automatically attached to any series added to the chart after this function has been called. A series with no axes attached will by default scale to utilize the entire plot area of the chart, which can be confusing if there are other series with properly attached axes also present.

Series type	Horizontal axis (X)	Vertical axis (Y)
QXYSeries	QValueAxis	QValueAxis
QBarSeries	QBarCategoryAxis	QValueAxis
QPieSeries	None	None

If there are several QXYSeries derived series added to the chart and no series of other types have been added, then only one pair of axes is created. If there are several series of different types added to the chart, then each series gets its own axes pair.

The axes specific to the series can be later obtained from the chart by providing the series as the parameter for the axes() function call. QPieSeries does not create any axes.

See also axes() and QAbstractSeries::attachAxis().

bool QChart::isZoomed()

Returns true if any series has a zoomed domain.

QLegend *QChart::legend() const

Returns the legend object of the chart. Ownership stays with the chart.

QPointF QChart::mapToPosition(const QPointF &value, QAbstractSeries *series = nullptr)

Returns the position on the chart that corresponds to the value value in the series specified by series.

QPointF QChart::mapToValue(const QPointF &position, QAbstractSeries *series = nullptr)

Returns the value in the series specified by series at the position specified by position in a chart.

QBrush QChart::plotAreaBackgroundBrush() const

Returns the brush used to fill the background of the plot area of the chart.

See also plotArea(), plotAreaBackgroundVisible, plotAreaBackgroundPen(), and setPlotAreaBackgroundBrush().

QPen QChart::plotAreaBackgroundPen() const

Returns the pen used to draw the background of the plot area of the chart.

See also plotArea(), plotAreaBackgroundVisible, plotAreaBackgroundBrush(), and setPlotAreaBackgroundPen().

void QChart::removeAllSeries()

Removes and deletes all series objects that have been added to the chart.

See also addSeries() and removeSeries().

void QChart::removeAxis(QAbstractAxis *axis)

Removes the axis axis from the chart. The chart releases the ownership of the specified axis object.

See also addAxis(), createDefaultAxes(), and QAbstractSeries::detachAxis().

void QChart::removeSeries(QAbstractSeries *series)

Removes the series series from the chart. The chart releases the ownership of the specified series object.

See also addSeries() and removeAllSeries().

void QChart::scroll(qreal dx, qreal dy)

Scrolls the visible area of the chart by the distance specified by dx and dy.

For polar charts, dx indicates the angle along the angular axis instead of distance.

QList<QAbstractSeries *> QChart::series() const

Returns all series that are added to the chart.

See also addSeries(), removeSeries(), and removeAllSeries().

void QChart::setBackgroundBrush(const QBrush &brush)

Sets the brush that is used for painting the background of the chart area to brush.

See also backgroundBrush().

void QChart::setBackgroundPen(const QPen &pen)

Sets the pen that is used for painting the background of the chart area to pen.

See also backgroundPen().

void QChart::setPlotAreaBackgroundBrush(const QBrush &brush)

Sets the brush used to fill the background of the plot area of the chart to brush.

See also plotArea(), plotAreaBackgroundVisible, setPlotAreaBackgroundPen(), and plotAreaBackgroundBrush().

void QChart::setPlotAreaBackgroundPen(const QPen &pen)

Sets the pen used to draw the background of the plot area of the chart to pen.

See also plotArea(), plotAreaBackgroundVisible, setPlotAreaBackgroundBrush(), and plotAreaBackgroundPen().

void QChart::setTitleBrush(const QBrush &brush)

Sets the brush used for drawing the title text to brush.

See also titleBrush().

void QChart::setTitleFont(const QFont &font)

Sets the font that is used for drawing the chart title to font.

See also titleFont().

QBrush QChart::titleBrush() const

Returns the brush used for drawing the title text.

See also setTitleBrush().

QFont QChart::titleFont() const

Gets the font that is used for drawing the chart title.

See also setTitleFont().

void QChart::zoom(qreal factor)

Zooms into the view by the custom factor factor.

A factor over 1.0 zooms into the view and a factor between 0.0 and 1.0 zooms out of it.

void QChart::zoomIn()

Zooms into the view by a factor of two.

void QChart::zoomIn(const QRectF &rect)

Zooms into the view to a maximum level at which the rectangle rect is still fully visible.

Note: Applying a zoom may modify properties of attached axes, for instance QAbstractAxis::min and QAbstractAxis::max.

Note: This is not supported for polar charts.

void QChart::zoomOut()

Zooms out of the view by a factor of two.

void QChart::zoomReset()

Resets the series domains to what they were before any zoom method was called.

Note: This will also reset scrolling and explicit axis range settings specified between the first zoom operation and calling this method. If no zoom operation has been performed, this method does nothing.