QChart Class | Qt Charts 5.7

Qt 5.7 | Qt Charts | C++ Classes | QChart

Qt 5.7.1 Reference Documentation

# QChart Class

Main chart API for Qt Charts. More...

Header: | #include <QChart>
Inherited By: | QPolarChart

- List of all members, including inherited members

## Public Types

enum | AnimationOption { NoAnimation, GridAxisAnimations, SeriesAnimations, AllAnimations }
flags | AnimationOptions
enum | ChartTheme { ChartThemeLight, ChartThemeBlueCerulean, ChartThemeDark, ChartThemeBrownSand, ..., 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 : const QRectF plotAreaBackgroundVisible : bool theme : QChart::ChartTheme title : QString

## Public Functions

| QChart(QGraphicsItem *parent = Q_NULLPTR, Qt::WindowFlags wFlags = Qt::WindowFlags())
| ~QChart()
void | addAxis(QAbstractAxis *axis, Qt::Alignment alignment)
void | addSeries(QAbstractSeries *series)
int | animationDuration() const
QEasingCurve | animationEasingCurve() const
AnimationOptions | animationOptions() const
QList<QAbstractAxis *> | axes(Qt::Orientations orientation = Qt::Horizontal | Qt::Vertical, QAbstractSeries *series = Q_NULLPTR) const
QAbstractAxis * | axisX(QAbstractSeries *series = Q_NULLPTR) const
QAbstractAxis * | axisY(QAbstractSeries *series = Q_NULLPTR) const
QBrush | backgroundBrush() const
QPen | backgroundPen() const
qreal | backgroundRoundness() const
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 = Q_NULLPTR)
QPointF | mapToValue(const QPointF &position, QAbstractSeries *series = Q_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(AnimationOptions options)
void | setAxisX(QAbstractAxis *axis, QAbstractSeries *series = Q_NULLPTR)
void | setAxisY(QAbstractAxis *axis, QAbstractSeries *series = Q_NULLPTR)
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 | 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

Main chart API for Qt Charts.

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. If you simply want to show a chart in a layout, you can use the convenience class QChartView instead of QChart.

See also QChartView and QPolarChart.

## Member Type Documentation

### enum QChart::AnimationOption
flags QChart::AnimationOptions

For enabling/disabling animations. Defaults to NoAnimation.

Constant | Value
--- | ---
`QChart::NoAnimation` | `0x0`
`QChart::GridAxisAnimations` | `0x1`
`QChart::SeriesAnimations` | `0x2`
`QChart::AllAnimations` | `0x3`

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.

Constant | Value | Description
--- | --- | ---
`QChart::ChartThemeLight` | `0` | The default theme
`QChart::ChartThemeBlueCerulean` | `1` |
`QChart::ChartThemeDark` | `2` |
`QChart::ChartThemeBrownSand` | `3` |
`QChart::ChartThemeBlueNcs` | `4` |
`QChart::ChartThemeHighContrast` | `5` |
`QChart::ChartThemeBlueIcy` | `6` |
`QChart::ChartThemeQt` | `7` |

### enum QChart::ChartType

This enum describes the chart type.

Constant | Value
--- | ---
`QChart::ChartTypeUndefined` | `0`
`QChart::ChartTypeCartesian` | `1`
`QChart::ChartTypePolar` | `2`

## Property Documentation

### animationDuration : int

The duration of the animation for the chart.

Access functions:

int | animationDuration() const
void | setAnimationDuration(int msecs)

### animationEasingCurve : QEasingCurve

The easing curve of the animation for the chart.

Access functions:

QEasingCurve | animationEasingCurve() const
void | setAnimationEasingCurve(const QEasingCurve &curve)

### animationOptions : QChart::AnimationOptions

The animation options for the chart. Animations are enabled/disabled based on this setting.

Access functions:

AnimationOptions | animationOptions() const
void | setAnimationOptions(AnimationOptions options)

### backgroundRoundness : qreal

The diameter of the rounding circle at the corners of the chart background.

Access functions:

qreal | backgroundRoundness() const
void | setBackgroundRoundness(qreal diameter)

### backgroundVisible : bool

Specifies whether the chart background is visible or not.

Access functions:

bool | isBackgroundVisible() const
void | setBackgroundVisible(bool visible = true)

See also setBackgroundBrush(), setBackgroundPen(), and plotAreaBackgroundVisible.

### chartType : const QChart::ChartType

Chart type indicates if the chart is a cartesian chart or a polar chart. This property is set internally and it is read only.

Access functions:

ChartType | chartType() const

See also QPolarChart.

### dropShadowEnabled : bool

If set to true, the background drop shadow effect is enabled. If set to false, it is disabled. Note that the drop shadow effect depends on theme, which means the setting may be changed if you switch to another theme.

Access functions:

bool | isDropShadowEnabled() const
void | setDropShadowEnabled(bool enabled = true)

### locale : QLocale

Sets the locale used to format various chart labels when localizeNumbers is `true`. This also determines the locale used to format QDateTimeAxis labels regardless of localizeNumbers property. Defaults to application default locale at the time the chart is constructed.

This property was introduced in QtCharts 2.0.

Access functions:

QLocale | locale() const
void | setLocale(const QLocale &locale)

See also localizeNumbers.

### localizeNumbers : bool

When `true`, all generated numbers appearing in various series and axis labels will be localized using the QLocale set with the locale property. When `false`, the "C" locale is always used. Defaults to `false`.

Note: This property doesn't affect QDateTimeAxis labels, which always use the QLocale set with the locale property.

This property was introduced in QtCharts 2.0.

Access functions:

bool | localizeNumbers() const
void | setLocalizeNumbers(bool localize)

See also locale.

### margins : QMargins

Margins between the plot area (axes) and the edge of the chart widget.

Access functions:

QMargins | margins() const
void | setMargins(const QMargins &margins)

### plotArea : const QRectF

Holds the rectangle within which the drawing of the chart is done. It does not include the area defined by margins.

Access functions:

QRectF | plotArea() const

Notifier signal:

void | plotAreaChanged(const QRectF &plotArea)

### plotAreaBackgroundVisible : bool

Specifies whether the chart plot area background is visible or not.

Note: By default the plot area background is not visible and the plot area uses the general chart background.

Access functions:

bool | isPlotAreaBackgroundVisible() const
void | setPlotAreaBackgroundVisible(bool visible = true)

See also setPlotAreaBackgroundBrush(), setPlotAreaBackgroundPen(), and backgroundVisible.

### theme : QChart::ChartTheme

Theme is a built-in collection of UI style related settings applied for all visual elements of a chart, like colors, pens, brushes, and fonts of series, axes, title, and legend. Chart themes example shows an example with a few different themes.

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

Access functions:

QChart::ChartTheme | theme() const
void | setTheme(QChart::ChartTheme theme)

### title : QString

Title is the name (label) of a chart. It is shown as a headline on top of the chart. Chart title supports html formatting.

Access functions:

QString | title() const
void | setTitle(const QString &title)

## Member Function Documentation

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

Constructs a chart object which is a child of a parent. Parameter wFlags is passed to the QGraphicsWidget constructor.

### QChart::~QChart()

Destroys the chart object and its children, like series and axis objects added to it.

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

Adds the axis to the chart with alignment. The chart takes the ownership of the axis.

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

### void QChart::addSeries(QAbstractSeries *series)

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

Note: A newly added series is attached to no axes by default, including any axes that were 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 = Q_NULLPTR) const

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

See also addAxis() and createDefaultAxes().

### QAbstractAxis *QChart::axisX(QAbstractSeries *series = Q_NULLPTR) const

Returns a pointer to the horizontal axis attached to the specified series. If no series is specified, the first horizontal axis added to the chart is returned.

See also setAxisX(), addAxis(), and QAbstractSeries::attachAxis().

### QAbstractAxis *QChart::axisY(QAbstractSeries *series = Q_NULLPTR) const

Returns a pointer to the vertical axis attached to the specified series. If no series is specified, the first vertical axis added to the chart is returned.

See also setAxisY(), addAxis(), and QAbstractSeries::attachAxis().

### 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 | X-axis | Y-axis
--- | --- | ---
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 axes() function call. QPieSeries does not create any axes.

See also axisX(), axisY(), axes(), setAxisX(), setAxisY(), 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 = Q_NULLPTR)

Returns the position on the chart widget that corresponds to the value in the series domain.

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

Returns the value in the series domain that corresponds to the position relative to chart widget.

### QBrush QChart::plotAreaBackgroundBrush() const

Returns the brush for the background of the plot area of the chart.

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

### QPen QChart::plotAreaBackgroundPen() const

Returns the pen for 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 from the chart. The chart releases its ownership of the specified axis object.

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

### void QChart::removeSeries(QAbstractSeries *series)

Removes the series from the chart. The chart releases its 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 defined in the dx and dy.

For polar charts, dx indicates the angle along 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::setAxisX(QAbstractAxis *axis, QAbstractSeries *series = Q_NULLPTR)

Adds the axis to the chart and attaches it to the series as a bottom-aligned horizontal axis. The chart takes ownership of both the axis and the series. Any horizontal axes previously attached to the series are deleted.

See also axisX(), axisY(), setAxisY(), createDefaultAxes(), and QAbstractSeries::attachAxis().

### void QChart::setAxisY(QAbstractAxis *axis, QAbstractSeries *series = Q_NULLPTR)

Adds the axis to the chart and attaches it to the series as a left-aligned vertical axis. The chart takes ownership of both the axis and the series. Any vertical axes previously attached to the series are deleted.

See also axisX(), axisY(), setAxisX(), createDefaultAxes(), and QAbstractSeries::attachAxis().

### void QChart::setBackgroundBrush(const QBrush &brush)

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

See also backgroundBrush().

### void QChart::setBackgroundPen(const QPen &pen)

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

See also backgroundPen().

### void QChart::setPlotAreaBackgroundBrush(const QBrush &brush)

Sets the brush for the background of the plot area of the chart.

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

### void QChart::setPlotAreaBackgroundPen(const QPen &pen)

Sets the pen for the background of the plot area of the chart.

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

### void QChart::setTitleBrush(const QBrush &brush)

Sets the brush used for drawing the title text.

See also titleBrush().

### void QChart::setTitleFont(const QFont &font)

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

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 in the view by a custom factor.

A factor over 1.0 zooms the view in and factor between 0.0 and 1.0 zooms out.

### void QChart::zoomIn()

Zooms in the view by a factor of two.

### void QChart::zoomIn(const QRectF &rect)

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

Note: This is not supported for polar charts.

### void QChart::zoomOut()

Zooms out 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 that this will also reset any scrolls and explicit axis range settings done between the first zoom operation and calling this method. If no zoom operation has been done, this method does nothing.