內容

公共類型
特性
公共函數
重實現公共函數
靜態公共成員
詳細描述

QGraphicsSvgItem 類

The QGraphicsSvgItem 類是 QGraphicsItem 可用於渲染 SVG 文件的內容。更多...

頭：	#include <QGraphicsSvgItem>
qmake:	QT += svg
Since:	Qt 4.2
繼承：	QGraphicsObject

公共類型

enum	anonymous { Type }

特性

elementId : QString
maximumCacheSize : QSize

12 特性繼承自 QGraphicsObject
1 特性繼承自 QObject

公共函數

	QGraphicsSvgItem (QGraphicsItem * parent = nullptr)
	QGraphicsSvgItem (const QString & fileName , QGraphicsItem * parent = nullptr)
QString	elementId () const
QSize	maximumCacheSize () const
QSvgRenderer *	renderer () const
void	setElementId (const QString & id )
void	setMaximumCacheSize (const QSize & size )
void	setSharedRenderer (QSvgRenderer * renderer )

重實現公共函數

virtual QRectF	boundingRect () const override
virtual void	paint (QPainter * painter , const QStyleOptionGraphicsItem * option , QWidget * widget = nullptr) override
virtual int	type () const override

2 公共函數繼承自 QGraphicsObject
176 公共函數繼承自 QGraphicsItem
31 公共函數繼承自 QObject

靜態公共成員

const QMetaObject

staticMetaObject

9 靜態公共成員繼承自 QObject

額外繼承成員

1 公共槽繼承自 QObject
9 信號繼承自 QGraphicsObject
2 信號繼承自 QObject
1 保護函數繼承自 QGraphicsObject
24 保護函數繼承自 QGraphicsItem
9 保護函數繼承自 QObject
1 保護槽繼承自 QGraphicsObject

詳細描述

The QGraphicsSvgItem 類是 QGraphicsItem 可用於渲染 SVG 文件的內容。

QGraphicsSvgItem provides a way of rendering SVG files onto QGraphicsView . QGraphicsSvgItem can be created by passing the SVG file to be rendered to its constructor or by explicit setting a shared QSvgRenderer on it.

注意，設置 QSvgRenderer 在 QGraphicsSvgItem doesn't make the item take ownership of the renderer, therefore if using setSharedRenderer () method one has to make sure that the lifetime of the QSvgRenderer object will be at least as long as that of the QGraphicsSvgItem .

QGraphicsSvgItem provides a way of rendering only parts of the SVG files via the setElementId 。若 setElementId () method is called, only the SVG element (and its children) with the passed id will be renderer. This provides a convenient way of selectively rendering large SVG files that contain a number of discrete elements. For example the following code renders only jokers from a SVG file containing a whole card deck:

QSvgRenderer *renderer = new QSvgRenderer(QLatin1String("SvgCardDeck.svg"));
QGraphicsSvgItem *black = new QGraphicsSvgItem();
QGraphicsSvgItem *red   = new QGraphicsSvgItem();
black->setSharedRenderer(renderer);
black->setElementId(QLatin1String("black_joker"));
red->setSharedRenderer(renderer);
red->setElementId(QLatin1String("red_joker"));

Size of the item can be set via direct manipulation of the items transformation matrix.

By default the SVG rendering is cached using QGraphicsItem::DeviceCoordinateCache mode to speedup the display of items. Caching can be disabled by passing QGraphicsItem::NoCache 到 QGraphicsItem::setCacheMode () 方法。

另請參閱 QSvgWidget , Qt SVG C++ 類 , QGraphicsItem ，和 QGraphicsView .

成員類型文檔編製

enum QGraphicsSvgItem:: anonymous

特性文檔編製

elementId : QString

This property holds the element's XML ID.

該特性在 Qt 4.6 引入。

訪問函數：

QString	elementId () const
void	setElementId (const QString & id )

maximumCacheSize : QSize

This property holds the maximum size of the device coordinate cache for this item.

該特性在 Qt 4.6 引入。

訪問函數：

QSize	maximumCacheSize () const
void	setMaximumCacheSize (const QSize & size )

成員函數文檔編製

QGraphicsSvgItem:: QGraphicsSvgItem ( QGraphicsItem * parent = nullptr)

構造新的 SVG 項采用給定 parent .

QGraphicsSvgItem:: QGraphicsSvgItem (const QString & fileName , QGraphicsItem * parent = nullptr)

構造新的項采用給定 parent and loads the contents of the SVG file with the specified fileName .

`[override virtual]` QRectF QGraphicsSvgItem:: boundingRect () const

重實現自 QGraphicsItem::boundingRect ().

返迴此項的邊界矩形。

QString QGraphicsSvgItem:: elementId () const

Returns the XML ID the element that is currently being rendered. Returns an empty string if the whole file is being rendered.

注意： getter 函數對於特性 elementId .

另請參閱 setElementId ().

QSize QGraphicsSvgItem:: maximumCacheSize () const

Returns the current maximum size of the device coordinate cache for this item. If the item is cached using QGraphicsItem::DeviceCoordinateCache mode, caching is bypassed if the extension of the item in device coordinates is larger than the maximum size.

The default maximum cache size is 1024x768. QPixmapCache::cacheLimit () gives the cumulative bounds of the whole cache, whereas maximumCacheSize() refers to a maximum cache size for this particular item.

注意： getter 函數對於特性 maximumCacheSize .

另請參閱 setMaximumCacheSize () 和 QGraphicsItem::cacheMode ().

`[override virtual]` void QGraphicsSvgItem:: paint ( QPainter * painter , const QStyleOptionGraphicsItem * option , QWidget * widget = nullptr)

重實現自 QGraphicsItem::paint ().

QSvgRenderer *QGraphicsSvgItem:: renderer () const

Returns the currently use QSvgRenderer .

void QGraphicsSvgItem:: setElementId (const QString & id )

Sets the XML ID of the element to id .

注意： setter 函數對於特性 elementId .

另請參閱 elementId ().

void QGraphicsSvgItem:: setMaximumCacheSize (const QSize & size )

Sets the maximum device coordinate cache size of the item to size . If the item is cached using QGraphicsItem::DeviceCoordinateCache mode, caching is bypassed if the extension of the item in device coordinates is larger than size .

The cache corresponds to the QPixmap which is used to cache the results of the rendering. Use QPixmapCache::setCacheLimit () to set limitations on the whole cache and use setMaximumCacheSize() when setting cache size for individual items.

注意： setter 函數對於特性 maximumCacheSize .

另請參閱 maximumCacheSize () 和 QGraphicsItem::cacheMode ().

void QGraphicsSvgItem:: setSharedRenderer ( QSvgRenderer * renderer )

集 renderer to be a shared QSvgRenderer on the item. By using this method one can share the same QSvgRenderer on a number of items. This means that the SVG file will be parsed only once. QSvgRenderer passed to this method has to exist for as long as this item is used.

`[override virtual]` int QGraphicsSvgItem:: type () const

重實現自 QGraphicsItem::type ().

內容