内容

• 公共函数
• 重实现公共函数
• 详细描述

QGraphicsEllipseItem 类

The QGraphicsEllipseItem class provides an ellipse item that you can add to a QGraphicsScene . 更多...

头：	#include <QGraphicsEllipseItem>
qmake:	QT += widgets
Since:	Qt 4.2
继承：	QAbstractGraphicsShapeItem

• 所有成员列表，包括继承成员

公共函数

	QGraphicsEllipseItem (QGraphicsItem * parent = Q_NULLPTR)
	QGraphicsEllipseItem (const QRectF & rect , QGraphicsItem * parent = Q_NULLPTR)
	QGraphicsEllipseItem (qreal x , qreal y , qreal width , qreal height , QGraphicsItem * parent = Q_NULLPTR)
	~QGraphicsEllipseItem ()
QRectF	rect () const
void	setRect (const QRectF & rect )
void	setRect (qreal x , qreal y , qreal width , qreal height )
void	setSpanAngle (int angle )
void	setStartAngle (int angle )
int	spanAngle () const
int	startAngle () const

重实现公共函数

virtual QRectF	boundingRect () const
virtual bool	contains (const QPointF & point ) const
virtual bool	isObscuredBy (const QGraphicsItem * item ) const
virtual QPainterPath	opaqueArea () const
virtual void	paint (QPainter * painter , const QStyleOptionGraphicsItem * option , QWidget * widget = Q_NULLPTR)
virtual QPainterPath	shape () const
virtual int	type () const

• 6 公共函数继承自 QAbstractGraphicsShapeItem
• 176 公共函数继承自 QGraphicsItem

额外继承成员

• 2 静态公共成员继承自 QGraphicsItem
• 24 保护函数继承自 QGraphicsItem

详细描述

The QGraphicsEllipseItem class provides an ellipse item that you can add to a QGraphicsScene .

QGraphicsEllipseItem respresents an ellipse with a fill and an outline, and you can also use it for ellipse segments (see startAngle (), spanAngle ()).

To set the item's ellipse, pass a QRectF to QGraphicsEllipseItem 's constructor, or call setRect ()。 rect () function returns the current ellipse geometry.

QGraphicsEllipseItem uses the rect and the pen width to provide a reasonable implementation of boundingRect (), shape ()，和 contains ()。 paint () function draws the ellipse using the item's associated pen and brush, which you can set by calling setPen () 和 setBrush ().

另请参阅 QGraphicsPathItem , QGraphicsRectItem , QGraphicsPolygonItem , QGraphicsTextItem , QGraphicsLineItem , QGraphicsPixmapItem ，和 图形视图框架 .

成员函数文档编制

QGraphicsEllipseItem:: QGraphicsEllipseItem ( QGraphicsItem * parent = Q_NULLPTR)

构造 QGraphicsEllipseItem . parent 会被传递给 QAbstractGraphicsShapeItem 的构造函数。

另请参阅 QGraphicsScene::addItem ().

QGraphicsEllipseItem:: QGraphicsEllipseItem (const QRectF & rect , QGraphicsItem * parent = Q_NULLPTR)

构造 QGraphicsEllipseItem 使用 rect 作为默认矩形。 parent 会被传递给 QAbstractGraphicsShapeItem 的构造函数。

另请参阅 QGraphicsScene::addItem ().

QGraphicsEllipseItem:: QGraphicsEllipseItem ( qreal x , qreal y , qreal width , qreal height , QGraphicsItem * parent = Q_NULLPTR)

构造 QGraphicsEllipseItem using the rectangle defined by ( x , y ) 和给定 width and height , as the default rectangle. parent 会被传递给 QAbstractGraphicsShapeItem 的构造函数。

该函数在 Qt 4.3 引入。

另请参阅 QGraphicsScene::addItem ().

QGraphicsEllipseItem:: ~QGraphicsEllipseItem ()

销毁 QGraphicsEllipseItem .

[虚拟] QRectF QGraphicsEllipseItem:: boundingRect () const

重实现自 QGraphicsItem::boundingRect ().

[虚拟] bool QGraphicsEllipseItem:: contains (const QPointF & point ) const

重实现自 QGraphicsItem::contains ().

[虚拟] bool QGraphicsEllipseItem:: isObscuredBy (const QGraphicsItem * item ) const

重实现自 QGraphicsItem::isObscuredBy ().

[虚拟] QPainterPath QGraphicsEllipseItem:: opaqueArea () const

重实现自 QGraphicsItem::opaqueArea ().

[虚拟] void QGraphicsEllipseItem:: paint ( QPainter * painter , const QStyleOptionGraphicsItem * option , QWidget * widget = Q_NULLPTR)

重实现自 QGraphicsItem::paint ().

QRectF QGraphicsEllipseItem:: rect () const

Returns the item's ellipse geometry as a QRectF .

另请参阅 setRect () 和 QPainter::drawEllipse ().

void QGraphicsEllipseItem:: setRect (const QRectF & rect )

Sets the item's ellipse geometry to rect . The rectangle's left edge defines the left edge of the ellipse, and the rectangle's top edge describes the top of the ellipse. The height and width of the rectangle describe the height and width of the ellipse.

另请参阅 rect () 和 QPainter::drawEllipse ().

void QGraphicsEllipseItem:: setRect ( qreal x , qreal y , qreal width , qreal height )

将项的矩形设为矩形，定义通过 ( x , y ) 和给定 width and height .

此方便函数相当于调用 setRect(QRectF(x, y, width, height))

另请参阅 rect ().

void QGraphicsEllipseItem:: setSpanAngle ( int angle )

Sets the span angle for an ellipse segment to angle , which is in 16ths of a degree. This angle is used together with startAngle () to represent an ellipse segment (a pie). By default, the span angle is 5760 (360 * 16, a full ellipse).

另请参阅 spanAngle (), setStartAngle ()，和 QPainter::drawPie ().

void QGraphicsEllipseItem:: setStartAngle ( int angle )

Sets the start angle for an ellipse segment to angle , which is in 16ths of a degree. This angle is used together with spanAngle () for representing an ellipse segment (a pie). By default, the start angle is 0.

另请参阅 startAngle (), setSpanAngle ()，和 QPainter::drawPie ().

[虚拟] QPainterPath QGraphicsEllipseItem:: shape () const

重实现自 QGraphicsItem::shape ().

int QGraphicsEllipseItem:: spanAngle () const

Returns the span angle of an ellipse segment in 16ths of a degree. This angle is used together with startAngle () for representing an ellipse segment (a pie). By default, this function returns 5760 (360 * 16, a full ellipse).

另请参阅 setSpanAngle () 和 startAngle ().

int QGraphicsEllipseItem:: startAngle () const

Returns the start angle for an ellipse segment in 16ths of a degree. This angle is used together with spanAngle () for representing an ellipse segment (a pie). By default, the start angle is 0.

另请参阅 setStartAngle () 和 spanAngle ().

[虚拟] int QGraphicsEllipseItem:: type () const

重实现自 QGraphicsItem::type ().