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内容

QPieSeries Class

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

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

特性

公共函数

QPieSeries (QObject * parent = nullptr)
virtual ~QPieSeries ()
bool append (QPieSlice * slice )
bool append (QList<QPieSlice *> slices )
QPieSlice * append (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 (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 (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

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 )

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 ( 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 ( 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 .

[virtual] 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 ( 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 ( 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.