The QLogValueAxis class adds a logarithmic scale to a chart's axis. 更多...
头: | #include <QLogValueAxis> |
实例化: | LogValueAxis |
继承: | QAbstractAxis |
|
|
QLogValueAxis (QObject * parent = nullptr) | |
virtual | ~QLogValueAxis () |
qreal | base () const |
QString | labelFormat () const |
qreal | max () const |
qreal | min () const |
int | minorTickCount () const |
void | setBase (qreal base ) |
void | setLabelFormat (const QString & format ) |
void | setMax (qreal max ) |
void | setMin (qreal min ) |
void | setMinorTickCount (int minorTickCount ) |
void | setRange (qreal min , qreal max ) |
int | tickCount () const |
virtual QAbstractAxis::AxisType | type () const override |
void | baseChanged (qreal base ) |
void | labelFormatChanged (const QString & format ) |
void | maxChanged (qreal max ) |
void | minChanged (qreal min ) |
void | minorTickCountChanged (int minorTickCount ) |
void | rangeChanged (qreal min , qreal max ) |
void | tickCountChanged (int tickCount ) |
A logarithmic scale is a nonlinear scale that is based on orders of magnitude, so that each tick mark on the axis is the previous tick mark multiplied by a value.
注意: If QLogValueAxis is attached to a series with one or more points with negative or zero values on the associated dimension, the series will not be plotted at all. This is particularly relevant when XYModelMappers are used, since empty cells in models typically contain zero values.
This property holds the base of the logarithm.
The value has to be greater than 0 and cannot equal 1.
访问函数:
qreal | base () const |
void | setBase (qreal base ) |
通知程序信号:
void | baseChanged (qreal base ) |
此特性保持轴的标签格式。
格式字符串支持的以下转换说明符、长度修饰符和标志的提供通过
printf()
在标准 C++ 库:d、i、o、x、X、f、F、e、E、g、G、c。
若
QChart::localizeNumbers
is
true
,支持的说明符限于:d、e、E、f、g、G 和 i。另外,仅支持精度修饰符。其余格式来自默认
QLocale
对于应用程序。
访问函数:
QString | labelFormat () const |
void | setLabelFormat (const QString & format ) |
通知程序信号:
void | labelFormatChanged (const QString & format ) |
另请参阅 QString::asprintf ().
此特性保持轴的最大值。
When setting this property, the minimum value is adjusted if necessary, to ensure that the range remains valid. The value has to be greater than 0.
访问函数:
qreal | max () const |
void | setMax (qreal max ) |
通知程序信号:
void | maxChanged (qreal max ) |
此特性保持轴的最小值。
When setting this property, the maximum value is adjusted if necessary, to ensure that the range remains valid. The value has to be greater than 0.
访问函数:
qreal | min () const |
void | setMin (qreal min ) |
通知程序信号:
void | minChanged (qreal min ) |
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. Set the value to -1 and the number of grid lines between major ticks will be calculated automatically.
访问函数:
int | minorTickCount () const |
void | setMinorTickCount (int minorTickCount ) |
通知程序信号:
void | minorTickCountChanged (int minorTickCount ) |
This property holds the number of tick marks on the axis. This indicates how many grid lines are drawn on the chart. This value is read-only.
访问函数:
int | tickCount () const |
通知程序信号:
void | tickCountChanged (int tickCount ) |
Constructs an axis object that is a child of parent .
[signal]
void
QLogValueAxis::
baseChanged
(
qreal
base
)
此信号发射当 base of the logarithm of the axis changes.
注意: 通知程序信号对于特性 base .
[signal]
void
QLogValueAxis::
labelFormatChanged
(const
QString
&
format
)
此信号发射当 format 对于轴标签改变。
注意: 通知程序信号对于特性 labelFormat .
[signal]
void
QLogValueAxis::
maxChanged
(
qreal
max
)
This signal is emitted when the maximum value of the axis, specified by max ,改变。
注意: 通知程序信号对于特性 max .
[signal]
void
QLogValueAxis::
minChanged
(
qreal
min
)
This signal is emitted when the minimum value of the axis, specified by min ,改变。
注意: 通知程序信号对于特性 min .
[signal]
void
QLogValueAxis::
minorTickCountChanged
(
int
minorTickCount
)
This signal is emitted when the number of minor tick marks on the axis, specified by minorTickCount ,改变。
注意: 通知程序信号对于特性 minorTickCount .
[signal]
void
QLogValueAxis::
rangeChanged
(
qreal
min
,
qreal
max
)
This signal is emitted when the minimum or maximum value of the axis, specified by min and max ,改变。
[signal]
void
QLogValueAxis::
tickCountChanged
(
int
tickCount
)
This signal is emitted when the number of tick marks on the axis, specified by tickCount ,改变。
注意: 通知程序信号对于特性 tickCount .
[虚拟]
QLogValueAxis::
~QLogValueAxis
()
销毁对象。
设置范围从 min to max 在轴。若 min 大于 max ,此函数返回不做任何改变。
[override virtual]
QAbstractAxis::AxisType
QLogValueAxis::
type
() const
重实现: QAbstractAxis::type () const.
返回轴的类型。