QChart Class

成员函数

QChart::QChart(QGraphicsItem *parent = Q_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.

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.

参见 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.

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

参见 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.

参见 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.

参见 setAxisY(), addAxis(), and QAbstractSeries::attachAxis().

QBrush QChart::backgroundBrush() const

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

参见 setBackgroundBrush().

QPen QChart::backgroundPen() const

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

参见 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.

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.

参见 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 that corresponds to the value value in the series specified by series.

QPointF QChart::mapToValue(const QPointF &position, QAbstractSeries *series = Q_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.

参见 plotArea(), plotAreaBackgroundVisible, plotAreaBackgroundPen(), and setPlotAreaBackgroundBrush().

QPen QChart::plotAreaBackgroundPen() const

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

参见 plotArea(), plotAreaBackgroundVisible, plotAreaBackgroundBrush(), and setPlotAreaBackgroundPen().

void QChart::removeAllSeries()

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

参见 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.

参见 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.

参见 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.

参见 addSeries(), removeSeries(), and removeAllSeries().

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

Adds the axis axis to the chart and attaches it to the series 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.

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

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

Adds the axis axis to the chart and attaches it to the series 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.

参见 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 to brush.

参见 backgroundBrush().

void QChart::setBackgroundPen(const QPen &pen)

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

参见 backgroundPen().

void QChart::setPlotAreaBackgroundBrush(const QBrush &brush)

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

参见 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.

参见 plotArea(), plotAreaBackgroundVisible, setPlotAreaBackgroundBrush(), and plotAreaBackgroundPen().

void QChart::setTitleBrush(const QBrush &brush)

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

参见 titleBrush().

void QChart::setTitleFont(const QFont &font)

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

参见 titleFont().

QBrush QChart::titleBrush() const

Returns the brush used for drawing the title text.

参见 setTitleBrush().

QFont QChart::titleFont() const

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

参见 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: 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.