Qt 4.8: QGraphicsSvgItem Class Reference

Qt Reference Documentation

# QGraphicsSvgItem Class Reference

The QGraphicsSvgItem class is a QGraphicsItem that can be used to render the contents of SVG files. More...

     #include <QGraphicsSvgItem>

Inherits: QGraphicsObject.

This class was introduced in Qt 4.2.

- List of all members, including inherited members
- Obsolete members

## Properties

- elementId : QString
- maximumCacheSize : QSize

- 12 properties inherited from QGraphicsObject
- 1 property inherited from QObject

## Public Functions

| QGraphicsSvgItem ( QGraphicsItem * parent = 0 )
| QGraphicsSvgItem ( const QString & fileName, QGraphicsItem * parent = 0 )
QString | elementId () const
QSize | maximumCacheSize () const
QSvgRenderer * | renderer () const
void | setElementId ( const QString & id )
void | setMaximumCacheSize ( const QSize & size )
void | setSharedRenderer ( QSvgRenderer * renderer )

## Reimplemented Public Functions

virtual QRectF | boundingRect () const
virtual void | paint ( QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = 0 )
virtual int | type () const

- 2 public functions inherited from QGraphicsObject
- 29 public functions inherited from QObject
- 177 public functions inherited from QGraphicsItem

### Additional Inherited Members

- 1 public slot inherited from QObject
- 9 signals inherited from QGraphicsObject
- 1 signal inherited from QObject
- 7 static public members inherited from QObject
- 2 static public members inherited from QGraphicsItem
- 8 protected functions inherited from QObject
- 24 protected functions inherited from QGraphicsItem
- 1 protected slot inherited from QGraphicsObject

## Detailed Description

The QGraphicsSvgItem class is a QGraphicsItem that can be used to render the contents of SVG files.

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.

Note that setting QSvgRenderer on a 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. If 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 the setSize() method of the bounding rectangle or 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 to the QGraphicsItem::setCacheMode() method.

See also QSvgWidget, QtSvg Module, QGraphicsItem, and QGraphicsView.

## Property Documentation

### elementId : QString

This property holds the element's XML ID.

This property was introduced in Qt 4.6.

Access functions:

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

### maximumCacheSize : QSize

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

This property was introduced in Qt 4.6.

Access functions:

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

## Member Function Documentation

### QGraphicsSvgItem::QGraphicsSvgItem ( QGraphicsItem * parent = 0 )

Constructs a new SVG item with the given parent.

### QGraphicsSvgItem::QGraphicsSvgItem ( const QString & fileName, QGraphicsItem * parent = 0 )

Constructs a new item with the given parent and loads the contents of the SVG file with the specified fileName.

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

Reimplemented from QGraphicsItem::boundingRect().

Returns the bounding rectangle of this item.

### void QGraphicsSvgItem::paint ( QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = 0 )`[virtual]`

Reimplemented from QGraphicsItem::paint().

### QSvgRenderer * QGraphicsSvgItem::renderer () const

Returns the currently use QSvgRenderer.

### void QGraphicsSvgItem::setSharedRenderer ( QSvgRenderer * renderer )

Sets 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.

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

Reimplemented from QGraphicsItem::type().