内容

• 公共类型
• 特性
• 公共函数
• 信号
• 详细描述

QLegend 类

The QLegend 类显示图表的图例。 更多...

头：	#include <QLegend>
实例化：	图例
继承：	QGraphicsWidget

• 所有成员列表，包括继承成员

公共类型

enum	MarkerShape { MarkerShapeDefault, MarkerShapeRectangle, MarkerShapeCircle, MarkerShapeFromSeries }

特性

alignment : Qt::Alignment backgroundVisible : bool borderColor : QColor color : QColor font : QFont

labelColor : QColor markerShape : MarkerShape reverseMarkers : bool showToolTips : bool

• 14 特性继承自 QGraphicsWidget
• 12 特性继承自 QGraphicsObject
• 1 特性继承自 QObject

公共函数

	~QLegend ()
Qt::Alignment	alignment () const
void	attachToChart ()
QColor	borderColor ()
QBrush	brush () const
QColor	color ()
void	detachFromChart ()
QFont	font () const
bool	isAttachedToChart ()
bool	isBackgroundVisible () const
QBrush	labelBrush () const
QColor	labelColor () const
MarkerShape	markerShape () const
QList<QLegendMarker *>	markers (QAbstractSeries * series = Q_NULLPTR) const
QPen	pen () const
bool	reverseMarkers ()
void	setAlignment (Qt::Alignment alignment )
void	setBackgroundVisible (bool visible = true)
void	setBorderColor (QColor color )
void	setBrush (const QBrush & brush )
void	setColor (QColor color )
void	setFont (const QFont & font )
void	setLabelBrush (const QBrush & brush )
void	setLabelColor (QColor color )
void	setMarkerShape (MarkerShape shape )
void	setPen (const QPen & pen )
void	setReverseMarkers (bool reverseMarkers = true)
void	setShowToolTips (bool show )
bool	showToolTips () const

• 53 公共函数继承自 QGraphicsWidget
• 2 公共函数继承自 QGraphicsObject
• 35 公共函数继承自 QGraphicsLayoutItem
• 32 公共函数继承自 QObject
• 176 公共函数继承自 QGraphicsItem

信号

void	backgroundVisibleChanged (bool visible )
void	borderColorChanged (QColor color )
void	colorChanged (QColor color )
void	fontChanged (QFont font )
void	labelColorChanged (QColor color )
void	markerShapeChanged (MarkerShape shape )
void	reverseMarkersChanged (bool reverseMarkers )
void	showToolTipsChanged (bool showToolTips )

• 1 信号继承自 QGraphicsWidget
• 9 信号继承自 QGraphicsObject
• 2 信号继承自 QObject

额外继承成员

• 1 公共槽继承自 QGraphicsWidget
• 1 公共槽继承自 QObject
• 1 静态公共成员继承自 QGraphicsWidget
• 11 静态公共成员继承自 QObject
• 2 静态公共成员继承自 QGraphicsItem
• 24 保护函数继承自 QGraphicsWidget
• 1 保护函数继承自 QGraphicsObject
• 3 保护函数继承自 QGraphicsLayoutItem
• 9 保护函数继承自 QObject
• 24 保护函数继承自 QGraphicsItem
• 1 保护槽继承自 QGraphicsObject

详细描述

The QLegend 类显示图表的图例。

A legend is a graphical object that displays the legend of a chart. The legend state is updated by QChart when series change. By default, the legend is attached to the chart, but it can be detached to make it independent of chart layout. Legend objects cannot be created or deleted, but they can be referenced via the QChart 类。

另请参阅 QChart .

成员类型文档编制

enum QLegend:: MarkerShape

This enum describes the shape used when rendering legend marker items.

常量	值	描述
QLegend::MarkerShapeDefault	0	Default shape determined by QLegend is used for the marker. This value is supported only for individual QLegendMarker 项。
QLegend::MarkerShapeRectangle	1	Rectangular markers are used. Marker size is determined by font size.
QLegend::MarkerShapeCircle	2	Circular markers are used. Marker size is determined by font size.
QLegend::MarkerShapeFromSeries	3	The marker shape is determined by the series. In case of a scatter series, the legend marker looks like a scatter dot and is the same size as the dot. In case of a line or spline series, the legend marker looks like a small segment of the line. For other series types, rectangular markers are shown.

另请参阅 markerShape .

特性文档编制

alignment : Qt::Alignment

How the legend is aligned with the chart.

可以是 Qt::AlignTop , Qt::AlignBottom , Qt::AlignLeft , Qt::AlignRight . If you set more than one flag, the result is undefined.

访问函数：

Qt::Alignment	alignment () const
void	setAlignment (Qt::Alignment alignment )

backgroundVisible : bool

This property holds whether the legend background is visible.

访问函数：

bool	isBackgroundVisible () const
void	setBackgroundVisible (bool visible = true)

通知程序信号：

void	backgroundVisibleChanged (bool visible )

borderColor : QColor

This property holds the line color of the legend.

访问函数：

QColor	borderColor ()
void	setBorderColor (QColor color )

通知程序信号：

void	borderColorChanged (QColor color )

color : QColor

This property holds the background (brush) color of the legend.

If you change the color of the legend, the style of the legend brush is set to Qt::SolidPattern .

访问函数：

QColor	color ()
void	setColor (QColor color )

通知程序信号：

void	colorChanged (QColor color )

font : QFont

This property holds the font of the markers used by the legend.

访问函数：

QFont	font () const
QFont	font () const
void	setFont (const QFont & font )
void	setFont (const QFont & font )

通知程序信号：

void	fontChanged (QFont font )

labelColor : QColor

This property holds the color of the brush used to draw labels.

访问函数：

QColor	labelColor () const
void	setLabelColor (QColor color )

通知程序信号：

void	labelColorChanged (QColor color )

markerShape : MarkerShape

The default shape of the legend markers. The default value is MarkerShapeRectangle .

该特性在 Qt 5.9 引入。

访问函数：

MarkerShape	markerShape () const
void	setMarkerShape (MarkerShape shape )

通知程序信号：

void	markerShapeChanged (MarkerShape shape )

reverseMarkers : bool

This property holds whether reverse order is used for the markers in the legend.

此特性是 false 在默认情况下。

访问函数：

bool	reverseMarkers ()
void	setReverseMarkers (bool reverseMarkers = true)

通知程序信号：

void	reverseMarkersChanged (bool reverseMarkers )

showToolTips : bool

This property holds whether tooltips are shown when the text is truncated.

此特性是 false 在默认情况下。

访问函数：

bool	showToolTips () const
void	setShowToolTips (bool show )

通知程序信号：

void	showToolTipsChanged (bool showToolTips )

成员函数文档编制

QLegend:: ~QLegend ()

Destroys the legend object. The legend is always owned by a QChart , so an application should never call this function.

void QLegend:: attachToChart ()

Attaches the legend to a chart. The chart may adjust the layout of the legend.

[signal] void QLegend:: backgroundVisibleChanged ( bool visible )

This signal is emitted when the visibility of the legend background changes to visible .

注意： 通知程序信号对于特性 backgroundVisible .

[signal] void QLegend:: borderColorChanged ( QColor color )

This signal is emitted when the border color of the legend background changes to color .

注意： 通知程序信号对于特性 borderColor .

QBrush QLegend:: brush () const

Returns the brush used by the legend.

另请参阅 setBrush ().

[signal] void QLegend:: colorChanged ( QColor color )

This signal is emitted when the color of the legend background changes to color .

注意： 通知程序信号对于特性 color .

void QLegend:: detachFromChart ()

Detaches the legend from the chart. The chart will no longer adjust the layout of the legend.

[signal] void QLegend:: fontChanged ( QFont font )

This signal is emitted when the font of the markers of the legend changes to font .

注意： 通知程序信号对于特性 font .

bool QLegend:: isAttachedToChart ()

返回 true , if the legend is attached to a chart.

bool QLegend:: isBackgroundVisible () const

Returns the visibility of the legend background.

注意： Getter 函数对于特性 backgroundVisible .

QBrush QLegend:: labelBrush () const

Returns the brush used to draw labels.

另请参阅 setLabelBrush ().

[signal] void QLegend:: labelColorChanged ( QColor color )

This signal is emitted when the color of the brush used to draw the legend labels changes to color .

注意： 通知程序信号对于特性 labelColor .

QList < QLegendMarker *> QLegend:: markers ( QAbstractSeries * series = Q_NULLPTR) const

Returns the list of markers in the legend. The list can be filtered by specifying the series for which the markers are returned.

QPen QLegend:: pen () const

Returns the pen used by the legend.

另请参阅 setPen ().

[signal] void QLegend:: reverseMarkersChanged ( bool reverseMarkers )

This signal is emitted when the use of reverse order for the markers in the legend is changed to reverseMarkers .

注意： 通知程序信号对于特性 reverseMarkers .

void QLegend:: setBackgroundVisible ( bool visible = true)

Sets the visibility of the legend background to visible .

注意： Setter 函数对于特性 backgroundVisible .

另请参阅 isBackgroundVisible ().

void QLegend:: setBrush (const QBrush & brush )

设置 brush that is used to draw the background of the legend.

另请参阅 brush ().

void QLegend:: setLabelBrush (const QBrush & brush )

Sets the brush used to draw the legend labels to brush .

另请参阅 labelBrush ().

void QLegend:: setPen (const QPen & pen )

设置 pen that is used to draw the legend borders.

另请参阅 pen ().

void QLegend:: setShowToolTips ( bool show )

当 show is true , the legend labels will show a tooltip when the mouse hovers over them if the label itself is shown elided. This is false 在默认情况下。

注意： Setter 函数对于特性 showToolTips .

另请参阅 showToolTips ().

bool QLegend:: showToolTips () const

Returns whether the tooltips are shown for the legend labels when they are elided.

注意： Getter 函数对于特性 showToolTips .

另请参阅 setShowToolTips ().

[signal] void QLegend:: showToolTipsChanged ( bool showToolTips )

This signal is emitted when the visibility of tooltips is changed to showToolTips .

注意： 通知程序信号对于特性 showToolTips .