QValueAxis Class
The QValueAxis class adds values to a chart's axes. More...
Header: | #include <QValueAxis> |
Instantiated By: | ValueAxis |
Inherits: | QAbstractAxis |
Inherited By: |
Properties
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- 27 properties inherited from QAbstractAxis
Public Functions
QValueAxis(QObject *parent = nullptr) | |
virtual | ~QValueAxis() |
QString | labelFormat() const |
qreal | max() const |
qreal | min() const |
int | minorTickCount() const |
void | setLabelFormat(const QString &format) |
void | setMax(qreal max) |
void | setMin(qreal min) |
void | setMinorTickCount(int count) |
void | setRange(qreal min, qreal max) |
void | setTickCount(int count) |
int | tickCount() const |
Reimplemented Public Functions
virtual QAbstractAxis::AxisType | type() const |
- 58 public functions inherited from QAbstractAxis
Public Slots
void | applyNiceNumbers() |
Signals
void | labelFormatChanged(const QString &format) |
void | maxChanged(qreal max) |
void | minChanged(qreal min) |
void | minorTickCountChanged(int tickCount) |
void | rangeChanged(qreal min, qreal max) |
void | tickCountChanged(int tickCount) |
- 25 signals inherited from QAbstractAxis
Detailed Description
The QValueAxis class adds values to a chart's axes.
A value axis can be set up to show an axis line with tick marks, grid lines, and shades. The values on the axis are drawn at the positions of tick marks.
The following example code illustrates how to use the QValueAxis class:
QChartView *chartView = new QChartView; QLineSeries *series = new QLineSeries; // ... chartView->chart()->addSeries(series); QValueAxis *axisX = new QValueAxis; axisX->setRange(10, 20.5); axisX->setTickCount(10); axisX->setLabelFormat("%.2f"); chartView->chart()->setAxisX(axisX, series);
Property Documentation
labelFormat : QString
This property holds the label format of the axis.
The format string supports the following conversion specifiers, length modifiers, and flags provided by printf()
in the standard C++ library: d, i, o, x, X, f, F, e, E, g, G, c.
If QChart::localizeNumbers is true
, the supported specifiers are limited to: d, e, E, f, g, G, and i. Also, only the precision modifier is supported. The rest of the formatting comes from the default QLocale of the application.
Access functions:
QString | labelFormat() const |
void | setLabelFormat(const QString &format) |
Notifier signal:
void | labelFormatChanged(const QString &format) |
See also QString::asprintf().
max : qreal
This property holds the maximum value on the axis.
When setting this property, the minimum value is adjusted if necessary, to ensure that the range remains valid.
Access functions:
qreal | max() const |
void | setMax(qreal max) |
Notifier signal:
void | maxChanged(qreal max) |
min : qreal
This property holds the minimum value on the axis.
When setting this property, the maximum value is adjusted if necessary, to ensure that the range remains valid.
Access functions:
qreal | min() const |
void | setMin(qreal min) |
Notifier signal:
void | minChanged(qreal min) |
minorTickCount : int
This property holds the number of minor tick marks on the axis. This indicates how many grid lines are drawn between major ticks on the chart. Labels are not drawn for minor ticks. The default value is 0.
Access functions:
int | minorTickCount() const |
void | setMinorTickCount(int count) |
Notifier signal:
void | minorTickCountChanged(int tickCount) |
tickCount : int
This property holds the number of tick marks on the axis. This indicates how many grid lines are drawn on the chart. The default value is 5, and the number cannot be less than 2.
Access functions:
int | tickCount() const |
void | setTickCount(int count) |
Notifier signal:
void | tickCountChanged(int tickCount) |
Member Function Documentation
QValueAxis::QValueAxis(QObject *parent = nullptr)
Constructs an axis object that is a child of parent.
[virtual]
QValueAxis::~QValueAxis()
Destroys the object.
[slot]
void QValueAxis::applyNiceNumbers()
Modifies the current range and number of tick marks on the axis to look nice. The algorithm considers numbers that can be expressed as a form of 1*10^n, 2* 10^n, or 5*10^n to be nice numbers. These numbers are used for setting spacing for the tick marks.
See also setRange() and setTickCount().
[signal]
void QValueAxis::rangeChanged(qreal min, qreal max)
void QValueAxis::setRange(qreal min, qreal max)
Sets the range from min to max on the axis. If min is greater than max, this function returns without making any changes.
[virtual]
QAbstractAxis::AxisType QValueAxis::type() const
Reimplemented from QAbstractAxis::type().
Returns the type of the axis.