QPieSlice Class

The QPieSlice class represents a single slice in a pie series. 更多...

头：	`#include <QPieSlice>`
CMake:	`find_package(Qt6 REQUIRED COMPONENTS Graphs)` `target_link_libraries(mytarget PRIVATE Qt6::Graphs)`
qmake:	`QT += graphs`
在 QML：	PieSlice
继承：	QObject

所有成员列表，包括继承成员
QPieSlice is part of Qt Graphs C++ Classes for 2D .

公共类型

枚举类	LabelPosition { Outside, InsideHorizontal, InsideTangential, InsideNormal }

特性

angleSpan : const qreal
borderColor : QColor
borderWidth : qreal
color : QColor
explodeDistanceFactor : qreal
exploded : bool
label : QString
labelArmLengthFactor : qreal

labelColor : QColor
labelFont : QFont
labelPosition : LabelPosition
labelVisible : bool
percentage : const qreal
startAngle : const qreal
value : qreal

公共函数

	QPieSlice (QObject * parent = nullptr)
	QPieSlice (const QString & label , qreal value , QObject * parent = nullptr)
virtual	~QPieSlice () override
qreal	angleSpan () const
QColor	borderColor () const
qreal	borderWidth () const
QColor	color () const
qreal	explodeDistanceFactor () const
bool	isExploded () const
bool	isLabelVisible () const
QString	label () const
qreal	labelArmLengthFactor () const
QColor	labelColor () const
QFont	labelFont () const
QPieSlice::LabelPosition	labelPosition ()
qreal	percentage () const
QPieSeries *	series () const
void	setBorderColor (QColor color )
void	setBorderWidth (qreal borderWidth )
void	setColor (QColor color )
void	setExplodeDistanceFactor (qreal factor )
void	setExploded (bool exploded )
void	setLabel (const QString & label )
void	setLabelArmLengthFactor (qreal factor )
void	setLabelColor (QColor color )
void	setLabelFont (const QFont & font )
void	setLabelPosition (QPieSlice::LabelPosition position )
void	setLabelVisible (bool visible = true)
void	setValue (qreal value )
qreal	startAngle () const
qreal	value () const

信号

void	angleSpanChanged ()
void	borderColorChanged ()
void	borderWidthChanged ()
void	colorChanged ()
void	explodeDistanceFactorChanged ()
void	explodedChanged ()
void	labelArmLengthFactorChanged ()
void	labelChanged ()
void	labelColorChanged ()
void	labelFontChanged ()
void	labelPositionChanged ()
void	labelVisibleChanged ()
void	percentageChanged ()
void	startAngleChanged ()
void	valueChanged ()

详细描述

A pie slice has a value and a label. When the slice is added to a pie series, the QPieSeries object calculates the percentage of the slice compared with the sum of all slices in the series to determine the actual size of the slice in the graph.

By default, the label is hidden. If it is visible, it can be either located outside the slice and connected to it with an arm or centered inside the slice either horizontally or in parallel with the tangential or normal of the slice's arc.

By default, the visual appearance of the slice is set by a theme, but the theme can be overridden by specifying slice properties. However, if the theme is changed after the slices are customized, all customization will be lost.

To enable user interaction with the pie graph, some basic signals are emitted when users click pie slices or hover the mouse over them.

另请参阅 QPieSeries .

成员类型文档编制

enum class QPieSlice:: LabelPosition

This enum describes the position of the slice label.

常量	值	描述
`QPieSlice::LabelPosition::Outside`	`0`	The label is located outside the slice connected to it with an arm. This is the default value.
`QPieSlice::LabelPosition::InsideHorizontal`	`1`	The label is centered within the slice and laid out horizontally.
`QPieSlice::LabelPosition::InsideTangential`	`2`	The label is centered within the slice and rotated to be parallel with the tangential of the slice's arc.
`QPieSlice::LabelPosition::InsideNormal`	`3`	The label is centered within the slice and rotated to be parallel with the normal of the slice's arc.

特性文档编制

`[read-only]` angleSpan : const qreal

This property holds the span of the slice in degrees. A full pie is 360 degrees, where 0 degrees is at 12 a'clock. Updated automatically once the slice is added to the series.

访问函数：

qreal angleSpan () const

通知程序信号：

void	angleSpanChanged ()

borderColor : QColor

This property holds the color used to draw the slice border. This is a convenience property for modifying the slice.

访问函数：

QColor	borderColor () const
void	setBorderColor (QColor color )

通知程序信号：

void	borderColorChanged ()

另请参阅 borderWidth .

borderWidth : qreal

This property holds the width of the slice border. This is a convenience property for modifying the slice border width.

访问函数：

qreal	borderWidth () const
void	setBorderWidth (qreal borderWidth )

通知程序信号：

void	borderWidthChanged ()

另请参阅 borderColor .

color : QColor

This property holds the fill color of the slice. This is a convenience property for modifying the slice fill color.

访问函数：

QColor	color () const
void	setColor (QColor color )

通知程序信号：

void	colorChanged ()

explodeDistanceFactor : qreal

Determines how far away from the pie the slice is exploded.

1.0 means that the distance is the same as the radius.
0.5 means that the distance is half of the radius.

By default, the distance is 0.15

访问函数：

qreal	explodeDistanceFactor () const
void	setExplodeDistanceFactor (qreal factor )

通知程序信号：

void	explodeDistanceFactorChanged ()

另请参阅 exploded .

exploded : bool

This property holds whether the slice is separated from the pie.

访问函数：

bool	isExploded () const
void	setExploded (bool exploded )

通知程序信号：

void	explodedChanged ()

另请参阅 explodeDistanceFactor .

label : QString

This property holds the label of the slice.

注意： The string can be HTML formatted.

访问函数：

QString	label () const
void	setLabel (const QString & label )

通知程序信号：

void	labelChanged ()

另请参阅 labelVisible , labelFont ，和 labelArmLengthFactor .

labelArmLengthFactor : qreal

This property holds the length of the label arm. The factor is relative to the pie radius. For example:

1.0 means that the length is the same as the radius.
0.5 means that the length is half of the radius.

By default, the arm length is 0.15

访问函数：

qreal	labelArmLengthFactor () const
void	setLabelArmLengthFactor (qreal factor )

通知程序信号：

void	labelArmLengthFactorChanged ()

另请参阅 label , labelVisible ，和 labelFont .

labelColor : QColor

This property holds the color used to draw the slice label.

访问函数：

QColor	labelColor () const
void	setLabelColor (QColor color )

通知程序信号：

void	labelColorChanged ()

labelFont : QFont

This property holds the font used for drawing the label text.

访问函数：

QFont	labelFont () const
void	setLabelFont (const QFont & font )

通知程序信号：

void	labelFontChanged ()

另请参阅 label , labelVisible ，和 labelArmLengthFactor .

labelPosition : LabelPosition

This property holds the position of the slice label.

访问函数：

QPieSlice::LabelPosition	labelPosition ()
void	setLabelPosition (QPieSlice::LabelPosition position )

通知程序信号：

void	labelPositionChanged ()

另请参阅 label and labelVisible .

labelVisible : bool

This property holds the visibility of the slice label. By default, the label is not visible.

访问函数：

bool	isLabelVisible () const
void	setLabelVisible (bool visible = true)

通知程序信号：

void	labelVisibleChanged ()

另请参阅 label , labelFont ，和 labelArmLengthFactor .

`[read-only]` percentage : const qreal

This property holds the percentage of the slice compared to the sum of all slices in the series. The actual value ranges from 0.0 to 1.0. Updated automatically once the slice is added to the series.

访问函数：

qreal percentage () const

通知程序信号：

void	percentageChanged ()

另请参阅 value and QPieSeries::sum .

`[read-only]` startAngle : const qreal

This property holds the starting angle of this slice in the series it belongs to. A full pie is 360 degrees, where 0 degrees is at 12 a'clock. Updated automatically once the slice is added to the series.

访问函数：

qreal startAngle () const

通知程序信号：

void	startAngleChanged ()

value : qreal

This property holds the value of the slice.

注意： A negative value is converted to a positive value.

访问函数：

qreal	值 () const
void	setValue (qreal value )

通知程序信号：

void	valueChanged ()

另请参阅 percentage () 和 QPieSeries::sum ().

成员函数文档编制

`[explicit]` QPieSlice:: QPieSlice ( QObject * parent = nullptr)

Constructs an empty slice with the parent parent .

另请参阅 QPieSeries::append () 和 QPieSeries::insert ().

QPieSlice:: QPieSlice (const QString & label , qreal value , QObject * parent = nullptr)

Constructs an empty slice with the specified value , label ，和 parent .

另请参阅 QPieSeries::append () 和 QPieSeries::insert ().

`[override virtual noexcept]` QPieSlice:: ~QPieSlice ()

Removes the slice. The slice should not be removed if it has been added to a series.

QPieSeries *QPieSlice:: series () const

Returns the series that this slice belongs to.

另请参阅 QPieSeries::append ().

QPieSlice Class

公共类型

特性

公共函数

信号

详细描述

成员类型文档编制

enum class QPieSlice:: LabelPosition

特性文档编制

[read-only] angleSpan : const qreal

borderColor : QColor

borderWidth : qreal

color : QColor

explodeDistanceFactor : qreal

exploded : bool

label : QString

labelArmLengthFactor : qreal

labelColor : QColor

labelFont : QFont

labelPosition : LabelPosition

labelVisible : bool

[read-only] percentage : const qreal

[read-only] startAngle : const qreal

value : qreal

成员函数文档编制

[explicit] QPieSlice:: QPieSlice ( QObject * parent = nullptr)

QPieSlice:: QPieSlice (const QString & label , qreal value , QObject * parent = nullptr)

[override virtual noexcept] QPieSlice:: ~QPieSlice ()

QPieSeries *QPieSlice:: series () const

内容

`[read-only]` angleSpan : const qreal

`[read-only]` percentage : const qreal

`[read-only]` startAngle : const qreal

`[explicit]` QPieSlice:: QPieSlice ( QObject * parent = nullptr)

`[override virtual noexcept]` QPieSlice:: ~QPieSlice ()