QLogValue3DAxisFormatter Class

The QLogValue3DAxisFormatter class provides formatting rules for a logarithmic value axis. More...

Header: #include <QLogValue3DAxisFormatter>
qmake: QT += datavisualization
Since: QtDataVisualization 1.1
Instantiated By: LogValueAxis3DFormatter
Inherits: QValue3DAxisFormatter

This class was introduced in QtDataVisualization 1.1.

Properties

Public Functions

QLogValue3DAxisFormatter(QObject *parent = nullptr)
virtual ~QLogValue3DAxisFormatter()
bool autoSubGrid() const
qreal base() const
void setAutoSubGrid(bool enabled)
void setBase(qreal base)
void setShowEdgeLabels(bool enabled)
bool showEdgeLabels() const

Signals

void autoSubGridChanged(bool enabled)
void baseChanged(qreal base)
void showEdgeLabelsChanged(bool enabled)

Detailed Description

When a formatter is attached to a value axis, the axis range cannot include negative values or the zero.

See also QValue3DAxisFormatter.

Property Documentation

autoSubGrid : bool

This property holds whether sub-grid positions are generated automatically.

If this property value is set to true, the parent axis sub-segment count is ignored when calculating sub-grid line positions. The sub-grid positions are generated automatically according to the base property value. The number of sub-grid lines is set to the base value minus one, rounded down. This property is ignored when the base value is zero. Defaults to true.

Access functions:

bool autoSubGrid() const
void setAutoSubGrid(bool enabled)

Notifier signal:

void autoSubGridChanged(bool enabled)

See also base and QValue3DAxis::subSegmentCount.

base : qreal

This property holds the base of the logarithm used to map axis values.

If the base is non-zero, the parent axis segment count will be ignored when the grid line and label positions are calculated. If you want the range to be divided into equal segments like a normal value axis, set this property value to zero.

The base has to be zero or a positive value and it cannot be equal to one. Defaults to ten.

Access functions:

qreal base() const
void setBase(qreal base)

Notifier signal:

void baseChanged(qreal base)

See also QValue3DAxis::segmentCount.

showEdgeLabels : bool

This property holds whether the first and last label on the axis are visible.

When the base property value is non-zero, the whole axis range is often not equally divided into segments. The first and last segments are often smaller than the other segments. In extreme cases, this can lead to overlapping labels on the first and last two grid lines. By setting this property to false, you can suppress showing the minimum and maximum labels for the axis in cases where the segments do not exactly fit the axis. Defaults to true.

Access functions:

bool showEdgeLabels() const
void setShowEdgeLabels(bool enabled)

Notifier signal:

void showEdgeLabelsChanged(bool enabled)

See also base and QAbstract3DAxis::labels.

Member Function Documentation

QLogValue3DAxisFormatter::QLogValue3DAxisFormatter(QObject *parent = nullptr)

Constructs a new logarithmic value 3D axis formatter with the optional parent parent.

[virtual] QLogValue3DAxisFormatter::~QLogValue3DAxisFormatter()

Deletes the logarithmic value 3D axis formatter.