QDateTimeAxis Class

The QDateTimeAxis class adds dates and times to a chart's axis. More...

Header:	#include <QDateTimeAxis>
Instantiated By:	DateTimeAxis
Inherits:	QAbstractAxis

• List of all members, including inherited members

Properties

• format : QString
• max : QDateTime
• min : QDateTime
• tickCount : int

Public Functions

	QDateTimeAxis(QObject *parent = nullptr)
virtual	~QDateTimeAxis()
QString	format() const
QDateTime	max() const
QDateTime	min() const
void	setFormat(QString format)
void	setMax(QDateTime max)
void	setMin(QDateTime min)
void	setRange(QDateTime min, QDateTime max)
void	setTickCount(int count)
int	tickCount() const

Reimplemented Public Functions

virtual QAbstractAxis::AxisType

type() const override

Signals

void	formatChanged(QString format)
void	maxChanged(QDateTime max)
void	minChanged(QDateTime min)
void	rangeChanged(QDateTime min, QDateTime max)
void	tickCountChanged(int tickCount)

Detailed Description

QDateTimeAxis can be set up to show an axis line with tick marks, grid lines, and shades. The labels can be configured by setting an appropriate DateTime format. QDateTimeAxis works correctly with dates from 4714 BCE to 287396 CE. For other limitiations related to QDateTime, see QDateTime documentation.

Note: QDateTimeAxis is disabled on platforms that define qreal as float.

QDateTimeAxis can be used with any QXYSeries. To add a data point to the series, QDateTime::toMSecsSinceEpoch() is used:

QLineSeries *series = new QLineSeries;

QDateTime xValue;
xValue.setDate(QDate(2012, 1 , 18));
xValue.setTime(QTime(9, 34));
qreal yValue = 12;
series->append(xValue.toMSecsSinceEpoch(), yValue);

xValue.setDate(QDate(2013, 5 , 11));
xValue.setTime(QTime(11, 14));
qreal yValue = 22;
series->append(xValue.toMSecsSinceEpoch(), yValue);

The following code snippet illustrates adding the series to the chart and setting up QDateTimeAxis:

QChartView *chartView = new QChartView;
chartView->chart()->addSeries(series);

// ...
QDateTimeAxis *axisX = new QDateTimeAxis;
axisX->setFormat("dd-MM-yyyy h:mm");
chartView->chart()->setAxisX(axisX, series);

Member Function Documentation

QDateTimeAxis::QDateTimeAxis(QObject *parent = nullptr)

Constructs an axis object that is a child of parent.

[signal] void QDateTimeAxis::formatChanged(QString format)

This signal is emitted when the format of the axis changes.

Note: Notifier signal for property format.

[signal] void QDateTimeAxis::maxChanged(QDateTime max)

This signal is emitted when the maximum value of the axis, specified by max, changes.

Note: Notifier signal for property max.

[signal] void QDateTimeAxis::minChanged(QDateTime min)

This signal is emitted when the minimum value of the axis, specified by min, changes.

Note: Notifier signal for property min.

[signal] void QDateTimeAxis::rangeChanged(QDateTime min, QDateTime max)

This signal is emitted when the minimum or maximum value of the axis, specified by min and max, changes.

[signal] void QDateTimeAxis::tickCountChanged(int tickCount)

This signal is emitted when the number of tick marks on the axis, specified by tickCount, changes.

Note: Notifier signal for property tickCount.

[virtual] QDateTimeAxis::~QDateTimeAxis()

Destroys the object.

void QDateTimeAxis::setRange(QDateTime min, QDateTime max)

Sets the range on the axis from min to max. If min is greater than max, this function returns without making any changes.

void QDateTimeAxis::setTickCount(int count)

Sets the number of tick marks on the axis to count.

Note: Setter function for property tickCount.

See also tickCount().

int QDateTimeAxis::tickCount() const

Returns the number of tick marks on the axis.

Note: Getter function for property tickCount.

See also setTickCount().

[override virtual] QAbstractAxis::AxisType QDateTimeAxis::type() const

Reimplements: QAbstractAxis::type() const.

Returns the type of the axis.