内容

• 特性
• 公共函数
• 重实现公共函数
• 信号
• 详细描述

QPieSeries Class

The QPieSeries class presents data in pie charts. 更多...

头：	#include <QPieSeries>
实例化：	PieSeries
继承：	QAbstractSeries

• 所有成员列表，包括继承成员

特性

count : const int endAngle : qreal holeSize : qreal horizontalPosition : qreal

size : qreal startAngle : qreal sum : const qreal verticalPosition : qreal

公共函数

	QPieSeries (QObject * parent = nullptr)
virtual	~QPieSeries ()
bool	append (QPieSlice * slice )
bool	append (const QList<QPieSlice *> & slices )
QPieSlice *	append (const QString & label , qreal value )
void	clear ()
int	count () const
qreal	holeSize () const
qreal	horizontalPosition () const
bool	insert (int index , QPieSlice * slice )
bool	isEmpty () const
qreal	pieEndAngle () const
qreal	pieSize () const
qreal	pieStartAngle () const
bool	remove (QPieSlice * slice )
void	setHoleSize (qreal holeSize )
void	setHorizontalPosition (qreal relativePosition )
void	setLabelsPosition (QPieSlice::LabelPosition position )
void	setLabelsVisible (bool visible = true)
void	setPieEndAngle (qreal angle )
void	setPieSize (qreal relativeSize )
void	setPieStartAngle (qreal startAngle )
void	setVerticalPosition (qreal relativePosition )
QList<QPieSlice *>	slices () const
qreal	sum () const
bool	take (QPieSlice * slice )
qreal	verticalPosition () const
QPieSeries &	operator<< (QPieSlice * slice )

重实现公共函数

virtual QAbstractSeries::SeriesType

type () const override

信号

void	added (const QList<QPieSlice *> & slices )
void	clicked (QPieSlice * slice )
void	countChanged ()
void	doubleClicked (QPieSlice * slice )
void	hovered (QPieSlice * slice , bool state )
void	pressed (QPieSlice * slice )
void	released (QPieSlice * slice )
void	removed (const QList<QPieSlice *> & slices )
void	sumChanged ()

详细描述

A pie series consists of slices that are defined as QPieSlice objects. The slices can have any values as the QPieSeries object calculates the percentage of a slice compared with the sum of all slices in the series to determine the actual size of the slice in the chart.

Pie size and position on the chart are controlled by using relative values that range from 0.0 to 1.0. These relate to the actual chart rectangle.

By default, the pie is defined as a full pie. A partial pie can be created by setting a starting angle and angle span for the series. A full pie is 360 degrees, where 0 is at 12 a'clock.

见 pie chart example or donut chart example to learn how to use QPieSeries.

另请参阅 QPieSlice and QChart .

特性文档编制

[read-only] count : const int

This property holds the number of slices in the series.

访问函数：

int	count () const

通知程序信号：

void	countChanged ()

endAngle : qreal

This property holds the ending angle of the pie.

A full pie is 360 degrees, where 0 degrees is at 12 a'clock.

The default value is 360.

访问函数：

qreal	pieEndAngle () const
void	setPieEndAngle (qreal angle )

holeSize : qreal

This property holds the donut hole size.

The value is relative to the chart rectangle, so that:

• 0.0 is the minimum size (full pie drawn without a hole).
• 1.0 is the maximum size that can fit the chart (the donut has no width).

当设置此特性时， size property is adjusted if necessary, to ensure that the hole size is not greater than the pie size.

The default value is 0.0.

访问函数：

qreal	holeSize () const
void	setHoleSize (qreal holeSize )

horizontalPosition : qreal

This property holds the horizontal position of the pie.

The value is relative to the chart rectangle, so that:

• 0.0 is the absolute left.
• 1.0 is the absolute right.

The default value is 0.5 (center).

访问函数：

qreal	horizontalPosition () const
void	setHorizontalPosition (qreal relativePosition )

另请参阅 verticalPosition .

size : qreal

This property holds the pie size.

The value is relative to the chart rectangle, so that:

• 0.0 is the minimum size (pie not drawn).
• 1.0 is the maximum size that can fit the chart.

当设置此特性时， holeSize property is adjusted if necessary, to ensure that the hole size is not greater than the pie size.

The default value is 0.7.

访问函数：

qreal	pieSize () const
void	setPieSize (qreal relativeSize )

startAngle : qreal

This property holds the starting angle of the pie.

A full pie is 360 degrees, where 0 degrees is at 12 a'clock.

默认值为 0。

访问函数：

qreal	pieStartAngle () const
void	setPieStartAngle (qreal startAngle )

[read-only] sum : const qreal

This property holds the sum of all slices.

The series keeps track of the sum of all the slices it holds.

访问函数：

qreal

sum () const

通知程序信号：

void	sumChanged ()

verticalPosition : qreal

This property holds the vertical position of the pie.

The value is relative to the chart rectangle, so that:

• 0.0 is the absolute top.
• 1.0 is the absolute bottom.

The default value is 0.5 (center).

访问函数：

qreal	verticalPosition () const
void	setVerticalPosition (qreal relativePosition )

另请参阅 horizontalPosition .

成员函数文档编制

QPieSeries:: QPieSeries ( QObject * parent = nullptr)

Constructs a series object that is a child of parent .

[signal] void QPieSeries:: added (const QList < QPieSlice *> & slices )

This signal is emitted when the slices specified by slices are added to the series.

另请参阅 append () 和 insert ().

[signal] void QPieSeries:: clicked ( QPieSlice * slice )

This signal is emitted when the slice specified by slice 被点击。

另请参阅 QPieSlice::clicked ().

[signal] void QPieSeries:: countChanged ()

This signal is emitted when the slice count changes.

注意： 通知程序信号对于特性 count .

另请参阅 count .

[signal] void QPieSeries:: doubleClicked ( QPieSlice * slice )

This signal is emitted when the slice specified by slice is double-clicked.

另请参阅 QPieSlice::doubleClicked ().

[signal] void QPieSeries:: hovered ( QPieSlice * slice , bool state )

This signal is emitted when a mouse is hovered over the slice specified by slice . When the mouse moves over the slice, state turns true , and when the mouse moves away again, it turns false .

另请参阅 QPieSlice::hovered ().

[signal] void QPieSeries:: pressed ( QPieSlice * slice )

This signal is emitted when the user clicks the slice specified by slice and holds down the mouse button.

另请参阅 QPieSlice::pressed ().

[signal] void QPieSeries:: released ( QPieSlice * slice )

This signal is emitted when the user releases the mouse press on the slice specified by slice .

另请参阅 QPieSlice::released ().

[signal] void QPieSeries:: removed (const QList < QPieSlice *> & slices )

This signal is emitted when the slices specified by slices are removed from the series.

另请参阅 remove ().

[signal] void QPieSeries:: sumChanged ()

This signal is emitted when the sum of all slices changes.

注意： 通知程序信号对于特性 sum .

另请参阅 sum .

[虚拟] QPieSeries:: ~QPieSeries ()

Removes the pie series and its slices.

bool QPieSeries:: append ( QPieSlice * slice )

Appends the slice specified by slice to the series. Slice ownership is passed to the series.

返回 true if appending succeeds.

bool QPieSeries:: append (const QList < QPieSlice *> & slices )

Appends the array of slices specified by slices to the series. Slice ownership is passed to the series.

返回 true if appending succeeds.

QPieSlice *QPieSeries:: append (const QString & label , qreal value )

Appends a single slice with the specified value and label to the series. Slice ownership is passed to the series. Returns null if value is NaN , Inf ，或 -Inf and adds nothing to the series.

void QPieSeries:: clear ()

Clears all slices from the series.

int QPieSeries:: count () const

Returns the number of the slices in this series.

注意： getter 函数对于特性 count。

bool QPieSeries:: insert ( int index , QPieSlice * slice )

Inserts the slice specified by slice to the series before the slice at the position specified by index . Slice ownership is passed to the series.

返回 true if inserting succeeds.

bool QPieSeries:: isEmpty () const

返回 true if the series is empty.

qreal QPieSeries:: pieEndAngle () const

Returns the end angle of the pie.

A full pie is 360 degrees, where 0 degrees is at 12 a'clock.

注意： getter 函数对于特性 endAngle .

另请参阅 setPieEndAngle (), pieStartAngle ()，和 setPieStartAngle ().

bool QPieSeries:: remove ( QPieSlice * slice )

Removes a single slice, specified by slice , from the series and deletes it permanently.

The pointer cannot be referenced after this call.

返回 true if the removal succeeds.

void QPieSeries:: setLabelsPosition ( QPieSlice::LabelPosition position )

Sets the position of all the slice labels to position .

注意： This function affects only the current slices in the series. If a new slice is added, the default label position is QPieSlice::LabelOutside .

另请参阅 QPieSlice::labelPosition () 和 QPieSlice::setLabelPosition ().

void QPieSeries:: setLabelsVisible ( bool visible = true)

Sets the visibility of all slice labels to visible .

注意： This function affects only the current slices in the series. If a new slice is added, the default label visibility is false .

另请参阅 QPieSlice::isLabelVisible () 和 QPieSlice::setLabelVisible ().

void QPieSeries:: setPieEndAngle ( qreal angle )

Sets the end angle of the pie.

A full pie is 360 degrees, where 0 degrees is at 12 a'clock.

angle must be greater than the start angle.

注意： setter 函数对于特性 endAngle .

另请参阅 pieEndAngle (), pieStartAngle ()，和 setPieStartAngle ().

QList < QPieSlice *> QPieSeries:: slices () const

Returns a list of slices that belong to this series.

qreal QPieSeries:: sum () const

Returns the sum of all slice values in this series.

注意： Getter function for property sum.

另请参阅 QPieSlice::value (), QPieSlice::setValue ()，和 QPieSlice::percentage ().

bool QPieSeries:: take ( QPieSlice * slice )

Takes a single slice, specified by slice , from the series. Does not delete the slice object.

注意： The series remains the slice's parent object. You must set the parent object to take full ownership.

返回 true if the take operation was successful.

[override virtual] QAbstractSeries::SeriesType QPieSeries:: type () const

重实现访问函数为特性： QAbstractSeries::type .

Returns the type of the series.

QPieSeries &QPieSeries:: operator<< ( QPieSlice * slice )

Appends the slice specified by slice to the series and returns a reference to the series. Slice ownership is passed to the series.