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</style></head><body><table border="0" cellpadding="0" cellspacing="0" width="100%"><tr /><td align="left" valign="top" width="32"><img align="left" border="0" height="32" src="images/rb-logo.png" width="32" /></td><td width="1">  </td><td class="postheader" valign="center"><a href="index.html"><font color="#004faf">Home</font></a> · <a href="classes.html"><font color="#004faf">All Classes</font></a> · <a href="modules.html"><font color="#004faf">Modules</font></a></td></table><h1 align="center">QGraphicsScene Class Reference<br /><sup><sup>[<a href="qtgui.html">QtGui</a> module]</sup></sup></h1><p>The QGraphicsScene class provides a surface for managing a large
number of 2D graphical items. <a href="#details">More...</a></p>
<p>Inherits <a href="qobject.html">QObject</a>.</p><h3>Types</h3><ul><li><div class="fn" />enum <b><a href="qgraphicsscene.html#ItemIndexMethod-enum">ItemIndexMethod</a></b> { BspTreeIndex, NoIndex }</li><li><div class="fn" />enum <b><a href="qgraphicsscene.html#SceneLayer-enum">SceneLayer</a></b> { ItemLayer, BackgroundLayer, ForegroundLayer, AllLayers }</li><li><div class="fn" />class <b><a href="qgraphicsscene-scenelayers.html">SceneLayers</a></b></li></ul><h3>Methods</h3><ul><li><div class="fn" /><b><a href="qgraphicsscene.html#QGraphicsScene">__init__</a></b> (<i>self</i>, QObject <i>parent</i> = None)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#QGraphicsScene-2">__init__</a></b> (<i>self</i>, QRectF <i>sceneRect</i>, QObject <i>parent</i> = None)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#QGraphicsScene-3">__init__</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>width</i>, float <i>height</i>, QObject <i>parent</i> = None)</li><li><div class="fn" />QGraphicsItem <b><a href="qgraphicsscene.html#activePanel">activePanel</a></b> (<i>self</i>)</li><li><div class="fn" />QGraphicsWidget <b><a href="qgraphicsscene.html#activeWindow">activeWindow</a></b> (<i>self</i>)</li><li><div class="fn" />QGraphicsEllipseItem <b><a href="qgraphicsscene.html#addEllipse">addEllipse</a></b> (<i>self</i>, QRectF <i>rect</i>, QPen <i>pen</i> = QPen(), QBrush <i>brush</i> = QBrush())</li><li><div class="fn" />QGraphicsEllipseItem <b><a href="qgraphicsscene.html#addEllipse-2">addEllipse</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, QPen <i>pen</i> = QPen(), QBrush <i>brush</i> = QBrush())</li><li><div class="fn" /><b><a href="qgraphicsscene.html#addItem">addItem</a></b> (<i>self</i>, QGraphicsItem <i>item</i>)</li><li><div class="fn" />QGraphicsLineItem <b><a href="qgraphicsscene.html#addLine">addLine</a></b> (<i>self</i>, QLineF <i>line</i>, QPen <i>pen</i> = QPen())</li><li><div class="fn" />QGraphicsLineItem <b><a href="qgraphicsscene.html#addLine-2">addLine</a></b> (<i>self</i>, float <i>x1</i>, float <i>y1</i>, float <i>x2</i>, float <i>y2</i>, QPen <i>pen</i> = QPen())</li><li><div class="fn" />QGraphicsPathItem <b><a href="qgraphicsscene.html#addPath">addPath</a></b> (<i>self</i>, QPainterPath <i>path</i>, QPen <i>pen</i> = QPen(), QBrush <i>brush</i> = QBrush())</li><li><div class="fn" />QGraphicsPixmapItem <b><a href="qgraphicsscene.html#addPixmap">addPixmap</a></b> (<i>self</i>, QPixmap <i>pixmap</i>)</li><li><div class="fn" />QGraphicsPolygonItem <b><a href="qgraphicsscene.html#addPolygon">addPolygon</a></b> (<i>self</i>, QPolygonF <i>polygon</i>, QPen <i>pen</i> = QPen(), QBrush <i>brush</i> = QBrush())</li><li><div class="fn" />QGraphicsRectItem <b><a href="qgraphicsscene.html#addRect">addRect</a></b> (<i>self</i>, QRectF <i>rect</i>, QPen <i>pen</i> = QPen(), QBrush <i>brush</i> = QBrush())</li><li><div class="fn" />QGraphicsRectItem <b><a href="qgraphicsscene.html#addRect-2">addRect</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, QPen <i>pen</i> = QPen(), QBrush <i>brush</i> = QBrush())</li><li><div class="fn" />QGraphicsSimpleTextItem <b><a href="qgraphicsscene.html#addSimpleText">addSimpleText</a></b> (<i>self</i>, QString <i>text</i>, QFont <i>font</i> = QFont())</li><li><div class="fn" />QGraphicsTextItem <b><a href="qgraphicsscene.html#addText">addText</a></b> (<i>self</i>, QString <i>text</i>, QFont <i>font</i> = QFont())</li><li><div class="fn" />QGraphicsProxyWidget <b><a href="qgraphicsscene.html#addWidget">addWidget</a></b> (<i>self</i>, QWidget <i>widget</i>, Qt.WindowFlags <i>flags</i> = 0)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#advance">advance</a></b> (<i>self</i>)</li><li><div class="fn" />QBrush <b><a href="qgraphicsscene.html#backgroundBrush">backgroundBrush</a></b> (<i>self</i>)</li><li><div class="fn" />int <b><a href="qgraphicsscene.html#bspTreeDepth">bspTreeDepth</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#clear">clear</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#clearFocus">clearFocus</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#clearSelection">clearSelection</a></b> (<i>self</i>)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#collidingItems">collidingItems</a></b> (<i>self</i>, QGraphicsItem <i>item</i>, Qt.ItemSelectionMode <i>mode</i> = Qt.IntersectsItemShape)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#contextMenuEvent">contextMenuEvent</a></b> (<i>self</i>, QGraphicsSceneContextMenuEvent <i>event</i>)</li><li><div class="fn" />QGraphicsItemGroup <b><a href="qgraphicsscene.html#createItemGroup">createItemGroup</a></b> (<i>self</i>, list-of-QGraphicsItem <i>items</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#destroyItemGroup">destroyItemGroup</a></b> (<i>self</i>, QGraphicsItemGroup <i>group</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#dragEnterEvent">dragEnterEvent</a></b> (<i>self</i>, QGraphicsSceneDragDropEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#dragLeaveEvent">dragLeaveEvent</a></b> (<i>self</i>, QGraphicsSceneDragDropEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#dragMoveEvent">dragMoveEvent</a></b> (<i>self</i>, QGraphicsSceneDragDropEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#drawBackground">drawBackground</a></b> (<i>self</i>, QPainter <i>painter</i>, QRectF <i>rect</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#drawForeground">drawForeground</a></b> (<i>self</i>, QPainter <i>painter</i>, QRectF <i>rect</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#drawItems">drawItems</a></b> (<i>self</i>, QPainter <i>painter</i>, list-of-QGraphicsItem <i>items</i>, list-of-QStyleOptionGraphicsItem <i>options</i>, QWidget <i>widget</i> = None)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#dropEvent">dropEvent</a></b> (<i>self</i>, QGraphicsSceneDragDropEvent <i>event</i>)</li><li><div class="fn" />bool <b><a href="qgraphicsscene.html#event">event</a></b> (<i>self</i>, QEvent <i>event</i>)</li><li><div class="fn" />bool <b><a href="qgraphicsscene.html#eventFilter">eventFilter</a></b> (<i>self</i>, QObject <i>watched</i>, QEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#focusInEvent">focusInEvent</a></b> (<i>self</i>, QFocusEvent <i>event</i>)</li><li><div class="fn" />QGraphicsItem <b><a href="qgraphicsscene.html#focusItem">focusItem</a></b> (<i>self</i>)</li><li><div class="fn" />bool <b><a href="qgraphicsscene.html#focusNextPrevChild">focusNextPrevChild</a></b> (<i>self</i>, bool <i>next</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#focusOutEvent">focusOutEvent</a></b> (<i>self</i>, QFocusEvent <i>event</i>)</li><li><div class="fn" />QFont <b><a href="qgraphicsscene.html#font">font</a></b> (<i>self</i>)</li><li><div class="fn" />QBrush <b><a href="qgraphicsscene.html#foregroundBrush">foregroundBrush</a></b> (<i>self</i>)</li><li><div class="fn" />bool <b><a href="qgraphicsscene.html#hasFocus">hasFocus</a></b> (<i>self</i>)</li><li><div class="fn" />float <b><a href="qgraphicsscene.html#height">height</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#helpEvent">helpEvent</a></b> (<i>self</i>, QGraphicsSceneHelpEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#inputMethodEvent">inputMethodEvent</a></b> (<i>self</i>, QInputMethodEvent <i>event</i>)</li><li><div class="fn" />QVariant <b><a href="qgraphicsscene.html#inputMethodQuery">inputMethodQuery</a></b> (<i>self</i>, Qt.InputMethodQuery <i>query</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#invalidate">invalidate</a></b> (<i>self</i>, QRectF <i>rect</i> = QRectF(), SceneLayers <i>layers</i> = QGraphicsScene.AllLayers)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#invalidate-2">invalidate</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, SceneLayers <i>layers</i> = QGraphicsScene.AllLayers)</li><li><div class="fn" />bool <b><a href="qgraphicsscene.html#isActive">isActive</a></b> (<i>self</i>)</li><li><div class="fn" />bool <b><a href="qgraphicsscene.html#isSortCacheEnabled">isSortCacheEnabled</a></b> (<i>self</i>)</li><li><div class="fn" />QGraphicsItem <b><a href="qgraphicsscene.html#itemAt">itemAt</a></b> (<i>self</i>, QPointF <i>pos</i>)</li><li><div class="fn" />QGraphicsItem <b><a href="qgraphicsscene.html#itemAt-2">itemAt</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>)</li><li><div class="fn" />QGraphicsItem <b><a href="qgraphicsscene.html#itemAt-3">itemAt</a></b> (<i>self</i>, QPointF <i>pos</i>, QTransform <i>deviceTransform</i>)</li><li><div class="fn" />QGraphicsItem <b><a href="qgraphicsscene.html#itemAt-4">itemAt</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, QTransform <i>deviceTransform</i>)</li><li><div class="fn" />ItemIndexMethod <b><a href="qgraphicsscene.html#itemIndexMethod">itemIndexMethod</a></b> (<i>self</i>)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items">items</a></b> (<i>self</i>)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-2">items</a></b> (<i>self</i>, Qt.SortOrder <i>order</i>)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-3">items</a></b> (<i>self</i>, QPointF <i>pos</i>)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-4">items</a></b> (<i>self</i>, QPointF <i>pos</i>, Qt.ItemSelectionMode <i>mode</i>, Qt.SortOrder <i>order</i>, QTransform <i>deviceTransform</i> = QTransform())</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-5">items</a></b> (<i>self</i>, QRectF <i>rectangle</i>, Qt.ItemSelectionMode <i>mode</i> = Qt.IntersectsItemShape)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-6">items</a></b> (<i>self</i>, QRectF <i>rect</i>, Qt.ItemSelectionMode <i>mode</i>, Qt.SortOrder <i>order</i>, QTransform <i>deviceTransform</i> = QTransform())</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-7">items</a></b> (<i>self</i>, QPolygonF <i>polygon</i>, Qt.ItemSelectionMode <i>mode</i> = Qt.IntersectsItemShape)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-8">items</a></b> (<i>self</i>, QPolygonF <i>polygon</i>, Qt.ItemSelectionMode <i>mode</i>, Qt.SortOrder <i>order</i>, QTransform <i>deviceTransform</i> = QTransform())</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-9">items</a></b> (<i>self</i>, QPainterPath <i>path</i>, Qt.ItemSelectionMode <i>mode</i> = Qt.IntersectsItemShape)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-10">items</a></b> (<i>self</i>, QPainterPath <i>path</i>, Qt.ItemSelectionMode <i>mode</i>, Qt.SortOrder <i>order</i>, QTransform <i>deviceTransform</i> = QTransform())</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-11">items</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, Qt.ItemSelectionMode <i>mode</i> = Qt.IntersectsItemShape)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#items-12">items</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, Qt.ItemSelectionMode <i>mode</i>, Qt.SortOrder <i>order</i>, QTransform <i>deviceTransform</i> = QTransform())</li><li><div class="fn" />QRectF <b><a href="qgraphicsscene.html#itemsBoundingRect">itemsBoundingRect</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#keyPressEvent">keyPressEvent</a></b> (<i>self</i>, QKeyEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#keyReleaseEvent">keyReleaseEvent</a></b> (<i>self</i>, QKeyEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#mouseDoubleClickEvent">mouseDoubleClickEvent</a></b> (<i>self</i>, QGraphicsSceneMouseEvent <i>event</i>)</li><li><div class="fn" />QGraphicsItem <b><a href="qgraphicsscene.html#mouseGrabberItem">mouseGrabberItem</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#mouseMoveEvent">mouseMoveEvent</a></b> (<i>self</i>, QGraphicsSceneMouseEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#mousePressEvent">mousePressEvent</a></b> (<i>self</i>, QGraphicsSceneMouseEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#mouseReleaseEvent">mouseReleaseEvent</a></b> (<i>self</i>, QGraphicsSceneMouseEvent <i>event</i>)</li><li><div class="fn" />QPalette <b><a href="qgraphicsscene.html#palette">palette</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#removeItem">removeItem</a></b> (<i>self</i>, QGraphicsItem <i>item</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#render">render</a></b> (<i>self</i>, QPainter <i>painter</i>, QRectF <i>target</i> = QRectF(), QRectF <i>source</i> = QRectF(), Qt.AspectRatioMode <i>mode</i> = Qt.KeepAspectRatio)</li><li><div class="fn" />QRectF <b><a href="qgraphicsscene.html#sceneRect">sceneRect</a></b> (<i>self</i>)</li><li><div class="fn" />list-of-QGraphicsItem <b><a href="qgraphicsscene.html#selectedItems">selectedItems</a></b> (<i>self</i>)</li><li><div class="fn" />QPainterPath <b><a href="qgraphicsscene.html#selectionArea">selectionArea</a></b> (<i>self</i>)</li><li><div class="fn" />bool <b><a href="qgraphicsscene.html#sendEvent">sendEvent</a></b> (<i>self</i>, QGraphicsItem <i>item</i>, QEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setActivePanel">setActivePanel</a></b> (<i>self</i>, QGraphicsItem <i>item</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setActiveWindow">setActiveWindow</a></b> (<i>self</i>, QGraphicsWidget <i>widget</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setBackgroundBrush">setBackgroundBrush</a></b> (<i>self</i>, QBrush <i>brush</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setBspTreeDepth">setBspTreeDepth</a></b> (<i>self</i>, int <i>depth</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setFocus">setFocus</a></b> (<i>self</i>, Qt.FocusReason <i>focusReason</i> = Qt.OtherFocusReason)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setFocusItem">setFocusItem</a></b> (<i>self</i>, QGraphicsItem <i>item</i>, Qt.FocusReason <i>focusReason</i> = Qt.OtherFocusReason)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setFont">setFont</a></b> (<i>self</i>, QFont <i>font</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setForegroundBrush">setForegroundBrush</a></b> (<i>self</i>, QBrush <i>brush</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setItemIndexMethod">setItemIndexMethod</a></b> (<i>self</i>, ItemIndexMethod <i>method</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setPalette">setPalette</a></b> (<i>self</i>, QPalette <i>palette</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setSceneRect">setSceneRect</a></b> (<i>self</i>, QRectF <i>rect</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setSceneRect-2">setSceneRect</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setSelectionArea">setSelectionArea</a></b> (<i>self</i>, QPainterPath <i>path</i>, QTransform <i>deviceTransform</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setSelectionArea-2">setSelectionArea</a></b> (<i>self</i>, QPainterPath <i>path</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setSelectionArea-3">setSelectionArea</a></b> (<i>self</i>, QPainterPath <i>path</i>, Qt.ItemSelectionMode)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setSelectionArea-4">setSelectionArea</a></b> (<i>self</i>, QPainterPath <i>path</i>, Qt.ItemSelectionMode <i>mode</i>, QTransform <i>deviceTransform</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setSortCacheEnabled">setSortCacheEnabled</a></b> (<i>self</i>, bool <i>enabled</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setStickyFocus">setStickyFocus</a></b> (<i>self</i>, bool <i>enabled</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#setStyle">setStyle</a></b> (<i>self</i>, QStyle <i>style</i>)</li><li><div class="fn" />bool <b><a href="qgraphicsscene.html#stickyFocus">stickyFocus</a></b> (<i>self</i>)</li><li><div class="fn" />QStyle <b><a href="qgraphicsscene.html#style">style</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#update">update</a></b> (<i>self</i>, QRectF <i>rect</i> = QRectF())</li><li><div class="fn" /><b><a href="qgraphicsscene.html#update-2">update</a></b> (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>)</li><li><div class="fn" />list-of-QGraphicsView <b><a href="qgraphicsscene.html#views">views</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsscene.html#wheelEvent">wheelEvent</a></b> (<i>self</i>, QGraphicsSceneWheelEvent <i>event</i>)</li><li><div class="fn" />float <b><a href="qgraphicsscene.html#width">width</a></b> (<i>self</i>)</li></ul><h3>Qt Signals</h3><ul><li><div class="fn" />void <b><a href="qgraphicsscene.html#changed">changed</a></b> (const QList<QRectF>&)</li><li><div class="fn" />void <b><a href="qgraphicsscene.html#sceneRectChanged">sceneRectChanged</a></b> (const QRectF&)</li><li><div class="fn" />void <b><a href="qgraphicsscene.html#selectionChanged">selectionChanged</a></b> ()</li></ul><a name="details" /><hr /><h2>Detailed Description</h2><p>The QGraphicsScene class provides a surface for managing a large
number of 2D graphical items.</p>
<p>The class serves as a container for QGraphicsItems. It is used
together with <a href="qgraphicsview.html">QGraphicsView</a> for
visualizing graphical items, such as lines, rectangles, text, or
even custom items, on a 2D surface. QGraphicsScene is part of the
<a href="graphicsview.html">Graphics View Framework</a>.</p>
<p>QGraphicsScene also provides functionality that lets you
efficiently determine both the location of items, and for
determining what items are visible within an arbitrary area on the
scene. With the <a href="qgraphicsview.html">QGraphicsView</a>
widget, you can either visualize the whole scene, or zoom in and
view only parts of the scene.</p>
<p>Example:</p>
<pre class="cpp">
<span class="type">QGraphicsScene</span> scene;
scene<span class="operator">.</span><a href="qgraphicsscene.html#addText">addText</a>(<span class="string">"Hello, world!"</span>);
<span class="type"><a href="qgraphicsview.html">QGraphicsView</a></span> view(<span class="operator">&</span>scene);
view<span class="operator">.</span>show();
</pre>
<p>Note that QGraphicsScene has no visual appearance of its own; it
only manages the items. You need to create a <a href="qgraphicsview.html">QGraphicsView</a> widget to visualize the
scene.</p>
<p>To add items to a scene, you start off by constructing a
QGraphicsScene object. Then, you have two options: either add your
existing <a href="qgraphicsitem.html">QGraphicsItem</a> objects by
calling <a href="qgraphicsscene.html#addItem">addItem</a>(), or you
can call one of the convenience functions <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPath">addPath</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addPolygon">addPolygon</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), or <a href="qgraphicsscene.html#addText">addText</a>(), which all return a
pointer to the newly added item. The dimensions of the items added
with these functions are relative to the item's coordinate system,
and the items position is initialized to (0, 0) in the scene.</p>
<p>You can then visualize the scene using <a href="qgraphicsview.html">QGraphicsView</a>. When the scene changes,
(e.g., when an item moves or is transformed) QGraphicsScene emits
the <a href="qgraphicsscene.html#changed">changed</a>() signal. To
remove an item, call <a href="qgraphicsscene.html#removeItem">removeItem</a>().</p>
<p>QGraphicsScene uses an indexing algorithm to manage the location
of items efficiently. By default, a BSP (Binary Space Partitioning)
tree is used; an algorithm suitable for large scenes where most
items remain static (i.e., do not move around). You can choose to
disable this index by calling <a href="qgraphicsscene.html#itemIndexMethod-prop">setItemIndexMethod</a>().
For more information about the available indexing algorithms, see
the <a href="qgraphicsscene.html#itemIndexMethod-prop">itemIndexMethod</a>
property.</p>
<p>The scene's bounding rect is set by calling <a href="qgraphicsscene.html#sceneRect-prop">setSceneRect</a>(). Items can
be placed at any position on the scene, and the size of the scene
is by default unlimited. The scene rect is used only for internal
bookkeeping, maintaining the scene's item index. If the scene rect
is unset, QGraphicsScene will use the bounding area of all items,
as returned by <a href="qgraphicsscene.html#itemsBoundingRect">itemsBoundingRect</a>(), as
the scene rect. However, <a href="qgraphicsscene.html#itemsBoundingRect">itemsBoundingRect</a>() is
a relatively time consuming function, as it operates by collecting
positional information for every item on the scene. Because of
this, you should always set the scene rect when operating on large
scenes.</p>
<p>One of QGraphicsScene's greatest strengths is its ability to
efficiently determine the location of items. Even with millions of
items on the scene, the <a href="qgraphicsscene.html#items">items</a>() functions can determine the
location of an item within few milliseconds. There are several
overloads to <a href="qgraphicsscene.html#items">items</a>(): one
that finds items at a certain position, one that finds items inside
or intersecting with a polygon or a rectangle, and more. The list
of returned items is sorted by stacking order, with the topmost
item being the first item in the list. For convenience, there is
also an <a href="qgraphicsscene.html#itemAt">itemAt</a>() function
that returns the topmost item at a given position.</p>
<p>QGraphicsScene maintains selection information for the scene. To
select items, call <a href="qgraphicsscene.html#setSelectionArea">setSelectionArea</a>(), and
to clear the current selection, call <a href="qgraphicsscene.html#clearSelection">clearSelection</a>(). Call
<a href="qgraphicsscene.html#selectedItems">selectedItems</a>() to
get the list of all selected items.</p>
<a id="event-handling-and-propagation" name="event-handling-and-propagation" />
<h3>Event Handling and Propagation</h3>
<p>Another responsibility that QGraphicsScene has, is to propagate
events from <a href="qgraphicsview.html">QGraphicsView</a>. To send
an event to a scene, you construct an event that inherits <a href="qevent.html">QEvent</a>, and then send it using, for example,
<a href="qcoreapplication.html#sendEvent">QApplication.sendEvent</a>().
<a href="qgraphicsscene.html#event">event</a>() is responsible for
dispatching the event to the individual items. Some common events
are handled by convenience event handlers. For example, key press
events are handled by <a href="qgraphicsscene.html#keyPressEvent">keyPressEvent</a>(), and mouse
press events are handled by <a href="qgraphicsscene.html#mousePressEvent">mousePressEvent</a>().</p>
<p>Key events are delivered to the <i>focus item</i>. To set the
focus item, you can either call <a href="qgraphicsscene.html#setFocusItem">setFocusItem</a>(), passing an
item that accepts focus, or the item itself can call <a href="qgraphicsitem.html#setFocus">QGraphicsItem.setFocus</a>(). Call
<a href="qgraphicsscene.html#focusItem">focusItem</a>() to get the
current focus item. For compatibility with widgets, the scene also
maintains its own focus information. By default, the scene does not
have focus, and all key events are discarded. If <a href="qgraphicsscene.html#setFocus">setFocus</a>() is called, or if an
item on the scene gains focus, the scene automatically gains focus.
If the scene has focus, <a href="qgraphicsscene.html#hasFocus">hasFocus</a>() will return true, and
key events will be forwarded to the focus item, if any. If the
scene loses focus, (i.e., someone calls <a href="qgraphicsscene.html#clearFocus">clearFocus</a>()) while an item
has focus, the scene will maintain its item focus information, and
once the scene regains focus, it will make sure the last focus item
regains focus.</p>
<p>For mouse-over effects, QGraphicsScene dispatches <i>hover
events</i>. If an item accepts hover events (see <a href="qgraphicsitem.html#acceptHoverEvents">QGraphicsItem.acceptHoverEvents</a>()),
it will receive a <a href="qevent.html#Type-enum">GraphicsSceneHoverEnter</a> event when the
mouse enters its area. As the mouse continues moving inside the
item's area, QGraphicsScene will send it <a href="qevent.html#Type-enum">GraphicsSceneHoverMove</a> events. When the
mouse leaves the item's area, the item will receive a <a href="qevent.html#Type-enum">GraphicsSceneHoverLeave</a> event.</p>
<p>All mouse events are delivered to the current <i>mouse
grabber</i> item. An item becomes the scene's mouse grabber if it
accepts mouse events (see <a href="qgraphicsitem.html#acceptedMouseButtons">QGraphicsItem.acceptedMouseButtons</a>())
and it receives a mouse press. It stays the mouse grabber until it
receives a mouse release when no other mouse buttons are pressed.
You can call <a href="qgraphicsscene.html#mouseGrabberItem">mouseGrabberItem</a>() to
determine what item is currently grabbing the mouse.</p>
<hr /><h2>Type Documentation</h2><h3 class="fn"><a name="ItemIndexMethod-enum" />QGraphicsScene.ItemIndexMethod</h3><p>This enum describes the indexing algorithms <a href="qgraphicsscene.html">QGraphicsScene</a> provides for managing
positional information about items on the scene.</p>
<table class="valuelist">
<tr class="odd" valign="top">
<th class="tblConst">Constant</th>
<th class="tblval">Value</th>
<th class="tbldscr">Description</th>
</tr>
<tr>
<td class="topAlign"><tt>QGraphicsScene.BspTreeIndex</tt></td>
<td class="topAlign"><tt>0</tt></td>
<td class="topAlign">A Binary Space Partitioning tree is applied.
All <a href="qgraphicsscene.html">QGraphicsScene</a>'s item
location algorithms are of an order close to logarithmic
complexity, by making use of binary search. Adding, moving and
removing items is logarithmic. This approach is best for static
scenes (i.e., scenes where most items do not move).</td>
</tr>
<tr>
<td class="topAlign"><tt>QGraphicsScene.NoIndex</tt></td>
<td class="topAlign"><tt>-1</tt></td>
<td class="topAlign">No index is applied. Item location is of
linear complexity, as all items on the scene are searched. Adding,
moving and removing items, however, is done in constant time. This
approach is ideal for dynamic scenes, where many items are added,
moved or removed continuously.</td>
</tr>
</table>
<p><b>See also</b> <a href="qgraphicsscene.html#itemIndexMethod-prop">setItemIndexMethod</a>()
and <a href="qgraphicsscene.html#bspTreeDepth-prop">bspTreeDepth</a>.</p>
<h3 class="fn"><a name="SceneLayer-enum" />QGraphicsScene.SceneLayer</h3><p>This enum describes the rendering layers in a <a href="qgraphicsscene.html">QGraphicsScene</a>. When <a href="qgraphicsscene.html">QGraphicsScene</a> draws the scene contents,
it renders each of these layers separately, in order.</p>
<p>Each layer represents a flag that can be OR'ed together when
calling functions such as <a href="qgraphicsscene.html#invalidate">invalidate</a>() or <a href="qgraphicsview.html#invalidateScene">QGraphicsView.invalidateScene</a>().</p>
<table class="valuelist">
<tr class="odd" valign="top">
<th class="tblConst">Constant</th>
<th class="tblval">Value</th>
<th class="tbldscr">Description</th>
</tr>
<tr>
<td class="topAlign"><tt>QGraphicsScene.ItemLayer</tt></td>
<td class="topAlign"><tt>0x1</tt></td>
<td class="topAlign">The item layer. <a href="qgraphicsscene.html">QGraphicsScene</a> renders all items are in
this layer by calling the virtual function <a class="obsolete" href="qgraphicsscene-obsolete.html#drawItems">drawItems</a>(). The item layer is drawn after the
background layer, but before the foreground layer.</td>
</tr>
<tr>
<td class="topAlign"><tt>QGraphicsScene.BackgroundLayer</tt></td>
<td class="topAlign"><tt>0x2</tt></td>
<td class="topAlign">The background layer. <a href="qgraphicsscene.html">QGraphicsScene</a> renders the scene's
background in this layer by calling the virtual function <a href="qgraphicsscene.html#drawBackground">drawBackground</a>(). The
background layer is drawn first of all layers.</td>
</tr>
<tr>
<td class="topAlign"><tt>QGraphicsScene.ForegroundLayer</tt></td>
<td class="topAlign"><tt>0x4</tt></td>
<td class="topAlign">The foreground layer. <a href="qgraphicsscene.html">QGraphicsScene</a> renders the scene's
foreground in this layer by calling the virtual function <a href="qgraphicsscene.html#drawForeground">drawForeground</a>(). The
foreground layer is drawn last of all layers.</td>
</tr>
<tr>
<td class="topAlign"><tt>QGraphicsScene.AllLayers</tt></td>
<td class="topAlign"><tt>0xffff</tt></td>
<td class="topAlign">All layers; this value represents a
combination of all three layers.</td>
</tr>
</table>
<p>This enum was introduced or modified in Qt 4.3.</p>
<p>The SceneLayers type is a typedef for <a href="qflags.html">QFlags</a><SceneLayer>. It stores an OR
combination of SceneLayer values.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#invalidate">invalidate</a>() and <a href="qgraphicsview.html#invalidateScene">QGraphicsView.invalidateScene</a>().</p>
<hr /><h2>Method Documentation</h2><h3 class="fn"><a name="QGraphicsScene" />QGraphicsScene.__init__ (<i>self</i>, <a href="qobject.html">QObject</a> <i>parent</i> = None)</h3><p>The <i>parent</i> argument, if not None, causes <i>self</i> to be owned by Qt instead of PyQt.</p><p>Constructs a <a href="qgraphicsscene.html">QGraphicsScene</a>
object. The <i>parent</i> parameter is passed to <a href="qobject.html">QObject</a>'s constructor.</p>
<h3 class="fn"><a name="QGraphicsScene-2" />QGraphicsScene.__init__ (<i>self</i>, <a href="qrectf.html">QRectF</a> <i>sceneRect</i>, <a href="qobject.html">QObject</a> <i>parent</i> = None)</h3><p>The <i>parent</i> argument, if not None, causes <i>self</i> to be owned by Qt instead of PyQt.</p><p>Constructs a <a href="qgraphicsscene.html">QGraphicsScene</a>
object, using <i>sceneRect</i> for its scene rectangle. The
<i>parent</i> parameter is passed to <a href="qobject.html">QObject</a>'s constructor.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#sceneRect-prop">sceneRect</a>.</p>
<h3 class="fn"><a name="QGraphicsScene-3" />QGraphicsScene.__init__ (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>width</i>, float <i>height</i>, <a href="qobject.html">QObject</a> <i>parent</i> = None)</h3><p>The <i>parent</i> argument, if not None, causes <i>self</i> to be owned by Qt instead of PyQt.</p><p>Constructs a <a href="qgraphicsscene.html">QGraphicsScene</a>
object, using the rectangle specified by (<i>x</i>, <i>y</i>), and
the given <i>width</i> and <i>height</i> for its scene rectangle.
The <i>parent</i> parameter is passed to <a href="qobject.html">QObject</a>'s constructor.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#sceneRect-prop">sceneRect</a>.</p>
<h3 class="fn"><a name="activePanel" /><a href="qgraphicsitem.html">QGraphicsItem</a> QGraphicsScene.activePanel (<i>self</i>)</h3><p>Returns the current active panel, or 0 if no panel is currently
active.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setActivePanel">QGraphicsScene.setActivePanel</a>().</p>
<h3 class="fn"><a name="activeWindow" /><a href="qgraphicswidget.html">QGraphicsWidget</a> QGraphicsScene.activeWindow (<i>self</i>)</h3><p>Returns the current active window, or 0 if no window is
currently active.</p>
<p>This function was introduced in Qt 4.4.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setActiveWindow">QGraphicsScene.setActiveWindow</a>().</p>
<h3 class="fn"><a name="addEllipse" /><a href="qgraphicsellipseitem.html">QGraphicsEllipseItem</a> QGraphicsScene.addEllipse (<i>self</i>, <a href="qrectf.html">QRectF</a> <i>rect</i>, <a href="qpen.html">QPen</a> <i>pen</i> = QPen(), <a href="qbrush.html">QBrush</a> <i>brush</i> = QBrush())</h3><p>Creates and adds an ellipse item to the scene, and returns the
item pointer. The geometry of the ellipse is defined by
<i>rect</i>, and its pen and brush are initialized to <i>pen</i>
and <i>brush</i>.</p>
<p>Note that the item's geometry is provided in item coordinates,
and its position is initialized to (0, 0).</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPath">addPath</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addText">addText</a>(), <a href="qgraphicsscene.html#addItem">addItem</a>(), and <a href="qgraphicsscene.html#addWidget">addWidget</a>().</p>
<h3 class="fn"><a name="addEllipse-2" /><a href="qgraphicsellipseitem.html">QGraphicsEllipseItem</a> QGraphicsScene.addEllipse (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, <a href="qpen.html">QPen</a> <i>pen</i> = QPen(), <a href="qbrush.html">QBrush</a> <i>brush</i> = QBrush())</h3><p>This convenience function is equivalent to calling
addEllipse(<a href="qrectf.html">QRectF</a>(<i>x</i>, <i>y</i>,
<i>w</i>, <i>h</i>), <i>pen</i>, <i>brush</i>).</p>
<p>This function was introduced in Qt 4.3.</p>
<h3 class="fn"><a name="addItem" />QGraphicsScene.addItem (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>item</i>)</h3><p>The <i>item</i> argument has it's ownership transferred to Qt.</p><p>Adds or moves the <i>item</i> and all its childen to this scene.
This scene takes ownership of the <i>item</i>.</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p>If the item is already in a different scene, it will first be
removed from its old scene, and then added to this scene as a
top-level.</p>
<p><a href="qgraphicsscene.html">QGraphicsScene</a> will send
ItemSceneChange notifications to <i>item</i> while it is added to
the scene. If item does not currently belong to a scene, only one
notification is sent. If it does belong to scene already (i.e., it
is moved to this scene), <a href="qgraphicsscene.html">QGraphicsScene</a> will send an addition
notification as the item is removed from its previous scene.</p>
<p>If the item is a panel, the scene is active, and there is no
active panel in the scene, then the item will be activated.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#removeItem">removeItem</a>(), <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPath">addPath</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addText">addText</a>(), <a href="qgraphicsscene.html#addWidget">addWidget</a>(), and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="addLine" /><a href="qgraphicslineitem.html">QGraphicsLineItem</a> QGraphicsScene.addLine (<i>self</i>, <a href="qlinef.html">QLineF</a> <i>line</i>, <a href="qpen.html">QPen</a> <i>pen</i> = QPen())</h3><p>Creates and adds a line item to the scene, and returns the item
pointer. The geometry of the line is defined by <i>line</i>, and
its pen is initialized to <i>pen</i>.</p>
<p>Note that the item's geometry is provided in item coordinates,
and its position is initialized to (0, 0).</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addPath">addPath</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addText">addText</a>(), <a href="qgraphicsscene.html#addItem">addItem</a>(), and <a href="qgraphicsscene.html#addWidget">addWidget</a>().</p>
<h3 class="fn"><a name="addLine-2" /><a href="qgraphicslineitem.html">QGraphicsLineItem</a> QGraphicsScene.addLine (<i>self</i>, float <i>x1</i>, float <i>y1</i>, float <i>x2</i>, float <i>y2</i>, <a href="qpen.html">QPen</a> <i>pen</i> = QPen())</h3><p>This convenience function is equivalent to calling
addLine(<a href="qlinef.html">QLineF</a>(<i>x1</i>, <i>y1</i>,
<i>x2</i>, <i>y2</i>), <i>pen</i>).</p>
<p>This function was introduced in Qt 4.3.</p>
<h3 class="fn"><a name="addPath" /><a href="qgraphicspathitem.html">QGraphicsPathItem</a> QGraphicsScene.addPath (<i>self</i>, <a href="qpainterpath.html">QPainterPath</a> <i>path</i>, <a href="qpen.html">QPen</a> <i>pen</i> = QPen(), <a href="qbrush.html">QBrush</a> <i>brush</i> = QBrush())</h3><p>Creates and adds a path item to the scene, and returns the item
pointer. The geometry of the path is defined by <i>path</i>, and
its pen and brush are initialized to <i>pen</i> and
<i>brush</i>.</p>
<p>Note that the item's geometry is provided in item coordinates,
and its position is initialized to (0, 0).</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addText">addText</a>(), <a href="qgraphicsscene.html#addItem">addItem</a>(), and <a href="qgraphicsscene.html#addWidget">addWidget</a>().</p>
<h3 class="fn"><a name="addPixmap" /><a href="qgraphicspixmapitem.html">QGraphicsPixmapItem</a> QGraphicsScene.addPixmap (<i>self</i>, <a href="qpixmap.html">QPixmap</a> <i>pixmap</i>)</h3><p>Creates and adds a pixmap item to the scene, and returns the
item pointer. The pixmap is defined by <i>pixmap</i>.</p>
<p>Note that the item's geometry is provided in item coordinates,
and its position is initialized to (0, 0).</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPath">addPath</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addText">addText</a>(), <a href="qgraphicsscene.html#addItem">addItem</a>(), and <a href="qgraphicsscene.html#addWidget">addWidget</a>().</p>
<h3 class="fn"><a name="addPolygon" /><a href="qgraphicspolygonitem.html">QGraphicsPolygonItem</a> QGraphicsScene.addPolygon (<i>self</i>, <a href="qpolygonf.html">QPolygonF</a> <i>polygon</i>, <a href="qpen.html">QPen</a> <i>pen</i> = QPen(), <a href="qbrush.html">QBrush</a> <i>brush</i> = QBrush())</h3><p>Creates and adds a polygon item to the scene, and returns the
item pointer. The polygon is defined by <i>polygon</i>, and its pen
and brush are initialized to <i>pen</i> and <i>brush</i>.</p>
<p>Note that the item's geometry is provided in item coordinates,
and its position is initialized to (0, 0).</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPath">addPath</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addText">addText</a>(), <a href="qgraphicsscene.html#addItem">addItem</a>(), and <a href="qgraphicsscene.html#addWidget">addWidget</a>().</p>
<h3 class="fn"><a name="addRect" /><a href="qgraphicsrectitem.html">QGraphicsRectItem</a> QGraphicsScene.addRect (<i>self</i>, <a href="qrectf.html">QRectF</a> <i>rect</i>, <a href="qpen.html">QPen</a> <i>pen</i> = QPen(), <a href="qbrush.html">QBrush</a> <i>brush</i> = QBrush())</h3><p>Creates and adds a rectangle item to the scene, and returns the
item pointer. The geometry of the rectangle is defined by
<i>rect</i>, and its pen and brush are initialized to <i>pen</i>
and <i>brush</i>.</p>
<p>Note that the item's geometry is provided in item coordinates,
and its position is initialized to (0, 0). For example, if a
<a href="qrect.html">QRect</a>(50, 50, 100, 100) is added, its
top-left corner will be at (50, 50) relative to the origin in the
items coordinate system.</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addText">addText</a>(), <a href="qgraphicsscene.html#addItem">addItem</a>(), and <a href="qgraphicsscene.html#addWidget">addWidget</a>().</p>
<h3 class="fn"><a name="addRect-2" /><a href="qgraphicsrectitem.html">QGraphicsRectItem</a> QGraphicsScene.addRect (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, <a href="qpen.html">QPen</a> <i>pen</i> = QPen(), <a href="qbrush.html">QBrush</a> <i>brush</i> = QBrush())</h3><p>This convenience function is equivalent to calling
addRect(<a href="qrectf.html">QRectF</a>(<i>x</i>, <i>y</i>,
<i>w</i>, <i>h</i>), <i>pen</i>, <i>brush</i>).</p>
<p>This function was introduced in Qt 4.3.</p>
<h3 class="fn"><a name="addSimpleText" /><a href="qgraphicssimpletextitem.html">QGraphicsSimpleTextItem</a> QGraphicsScene.addSimpleText (<i>self</i>, QString <i>text</i>, <a href="qfont.html">QFont</a> <i>font</i> = QFont())</h3><p>Creates and adds a <a href="qgraphicssimpletextitem.html">QGraphicsSimpleTextItem</a> to the
scene, and returns the item pointer. The text string is initialized
to <i>text</i>, and its font is initialized to <i>font</i>.</p>
<p>The item's position is initialized to (0, 0).</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addItem">addItem</a>(), and <a href="qgraphicsscene.html#addWidget">addWidget</a>().</p>
<h3 class="fn"><a name="addText" /><a href="qgraphicstextitem.html">QGraphicsTextItem</a> QGraphicsScene.addText (<i>self</i>, QString <i>text</i>, <a href="qfont.html">QFont</a> <i>font</i> = QFont())</h3><p>Creates and adds a text item to the scene, and returns the item
pointer. The text string is initialized to <i>text</i>, and its
font is initialized to <i>font</i>.</p>
<p>The item's position is initialized to (0, 0).</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addItem">addItem</a>(), and <a href="qgraphicsscene.html#addWidget">addWidget</a>().</p>
<h3 class="fn"><a name="addWidget" /><a href="qgraphicsproxywidget.html">QGraphicsProxyWidget</a> QGraphicsScene.addWidget (<i>self</i>, <a href="qwidget.html">QWidget</a> <i>widget</i>, <a href="qt-windowflags.html">Qt.WindowFlags</a> <i>flags</i> = 0)</h3><p>The <i>widget</i> argument has it's ownership transferred to Qt.</p><p>Creates a new <a href="qgraphicsproxywidget.html">QGraphicsProxyWidget</a> for
<i>widget</i>, adds it to the scene, and returns a pointer to the
proxy. <i>wFlags</i> set the default window flags for the embedding
proxy widget.</p>
<p>The item's position is initialized to (0, 0).</p>
<p>If the item is visible (i.e., <a href="qgraphicsitem.html#isVisible">QGraphicsItem.isVisible</a>()
returns true), <a href="qgraphicsscene.html">QGraphicsScene</a>
will emit <a href="qgraphicsscene.html#changed">changed</a>() once
control goes back to the event loop.</p>
<p>Note that widgets with the <a href="qt.html#WidgetAttribute-enum">Qt.WA_PaintOnScreen</a> widget
attribute set and widgets that wrap an external application or
controller are not supported. Examples are <a href="qglwidget.html">QGLWidget</a> and <a href="qaxwidget.html">QAxWidget</a>.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addEllipse">addEllipse</a>(), <a href="qgraphicsscene.html#addLine">addLine</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addPixmap">addPixmap</a>(), <a href="qgraphicsscene.html#addRect">addRect</a>(), <a href="qgraphicsscene.html#addText">addText</a>(), <a href="qgraphicsscene.html#addSimpleText">addSimpleText</a>(), and
<a href="qgraphicsscene.html#addItem">addItem</a>().</p>
<h3 class="fn"><a name="advance" />QGraphicsScene.advance (<i>self</i>)</h3><p>This method is also a Qt slot with the C++ signature <tt>void advance()</tt>.</p><p>This slot <i>advances</i> the scene by one step, by calling
<a href="qgraphicsitem.html#advance">QGraphicsItem.advance</a>()
for all items on the scene. This is done in two phases: in the
first phase, all items are notified that the scene is about to
change, and in the second phase all items are notified that they
can move. In the first phase, <a href="qgraphicsitem.html#advance">QGraphicsItem.advance</a>() is called
passing a value of 0 as an argument, and 1 is passed in the second
phase.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#advance">QGraphicsItem.advance</a>(), <a href="qgraphicsitemanimation.html">QGraphicsItemAnimation</a>, and
<a href="qtimeline.html">QTimeLine</a>.</p>
<h3 class="fn"><a name="backgroundBrush" /><a href="qbrush.html">QBrush</a> QGraphicsScene.backgroundBrush (<i>self</i>)</h3><h3 class="fn"><a name="bspTreeDepth" />int QGraphicsScene.bspTreeDepth (<i>self</i>)</h3><h3 class="fn"><a name="clear" />QGraphicsScene.clear (<i>self</i>)</h3><p>This method is also a Qt slot with the C++ signature <tt>void clear()</tt>.</p><p>Removes and deletes all items from the scene, but otherwise
leaves the state of the scene unchanged.</p>
<p>This function was introduced in Qt 4.4.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addItem">addItem</a>().</p>
<h3 class="fn"><a name="clearFocus" />QGraphicsScene.clearFocus (<i>self</i>)</h3><p>Clears focus from the scene. If any item has focus when this
function is called, it will lose focus, and regain focus again once
the scene regains focus.</p>
<p>A scene that does not have focus ignores key events.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#hasFocus">hasFocus</a>(), <a href="qgraphicsscene.html#setFocus">setFocus</a>(), and <a href="qgraphicsscene.html#setFocusItem">setFocusItem</a>().</p>
<h3 class="fn"><a name="clearSelection" />QGraphicsScene.clearSelection (<i>self</i>)</h3><p>Clears the current selection.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setSelectionArea">setSelectionArea</a>() and
<a href="qgraphicsscene.html#selectedItems">selectedItems</a>().</p>
<h3 class="fn"><a name="collidingItems" />list-of-QGraphicsItem QGraphicsScene.collidingItems (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>item</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i> = Qt.IntersectsItemShape)</h3><p>Returns a list of all items that collide with <i>item</i>.
Collisions are determined by calling <a href="qgraphicsitem.html#collidesWithItem">QGraphicsItem.collidesWithItem</a>();
the collision detection is determined by <i>mode</i>. By default,
all items whose shape intersects <i>item</i> or is contained inside
<i>item</i>'s shape are returned.</p>
<p>The items are returned in descending stacking order (i.e., the
first item in the list is the uppermost item, and the last item is
the lowermost item).</p>
<p><b>See also</b> <a href="qgraphicsscene.html#items">items</a>(),
<a href="qgraphicsscene.html#itemAt">itemAt</a>(), <a href="qgraphicsitem.html#collidesWithItem">QGraphicsItem.collidesWithItem</a>(),
and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="contextMenuEvent" />QGraphicsScene.contextMenuEvent (<i>self</i>, <a href="qgraphicsscenecontextmenuevent.html">QGraphicsSceneContextMenuEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>contextMenuEvent</i>, can be
reimplemented in a subclass to receive context menu events. The
default implementation forwards the event to the topmost item that
accepts context menu events at the position of the event. If no
items accept context menu events at this position, the event is
ignored.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#contextMenuEvent">QGraphicsItem.contextMenuEvent</a>().</p>
<h3 class="fn"><a name="createItemGroup" /><a href="qgraphicsitemgroup.html">QGraphicsItemGroup</a> QGraphicsScene.createItemGroup (<i>self</i>, list-of-QGraphicsItem <i>items</i>)</h3><p>The <i>items</i> argument has it's ownership transferred to Qt.</p><p>Groups all items in <i>items</i> into a new <a href="qgraphicsitemgroup.html">QGraphicsItemGroup</a>, and returns a
pointer to the group. The group is created with the common ancestor
of <i>items</i> as its parent, and with position (0, 0). The items
are all reparented to the group, and their positions and
transformations are mapped to the group. If <i>items</i> is empty,
this function will return an empty top-level <a href="qgraphicsitemgroup.html">QGraphicsItemGroup</a>.</p>
<p><a href="qgraphicsscene.html">QGraphicsScene</a> has ownership
of the group item; you do not need to delete it. To dismantle
(ungroup) a group, call <a href="qgraphicsscene.html#destroyItemGroup">destroyItemGroup</a>().</p>
<p><b>See also</b> <a href="qgraphicsscene.html#destroyItemGroup">destroyItemGroup</a>() and
<a href="qgraphicsitemgroup.html#addToGroup">QGraphicsItemGroup.addToGroup</a>().</p>
<h3 class="fn"><a name="destroyItemGroup" />QGraphicsScene.destroyItemGroup (<i>self</i>, <a href="qgraphicsitemgroup.html">QGraphicsItemGroup</a> <i>group</i>)</h3><p>The <i>group</i> argument has it's ownership transferred to Qt.</p><p>Reparents all items in <i>group</i> to <i>group</i>'s parent
item, then removes <i>group</i> from the scene, and finally deletes
it. The items' positions and transformations are mapped from the
group to the group's parent.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#createItemGroup">createItemGroup</a>() and
<a href="qgraphicsitemgroup.html#removeFromGroup">QGraphicsItemGroup.removeFromGroup</a>().</p>
<h3 class="fn"><a name="dragEnterEvent" />QGraphicsScene.dragEnterEvent (<i>self</i>, <a href="qgraphicsscenedragdropevent.html">QGraphicsSceneDragDropEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>event</i>, can be reimplemented
in a subclass to receive drag enter events for the scene.</p>
<p>The default implementation accepts the event and prepares the
scene to accept drag move events.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#dragEnterEvent">QGraphicsItem.dragEnterEvent</a>(),
<a href="qgraphicsscene.html#dragMoveEvent">dragMoveEvent</a>(),
<a href="qgraphicsscene.html#dragLeaveEvent">dragLeaveEvent</a>(),
and <a href="qgraphicsscene.html#dropEvent">dropEvent</a>().</p>
<h3 class="fn"><a name="dragLeaveEvent" />QGraphicsScene.dragLeaveEvent (<i>self</i>, <a href="qgraphicsscenedragdropevent.html">QGraphicsSceneDragDropEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>event</i>, can be reimplemented
in a subclass to receive drag leave events for the scene.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#dragLeaveEvent">QGraphicsItem.dragLeaveEvent</a>(),
<a href="qgraphicsscene.html#dragEnterEvent">dragEnterEvent</a>(),
<a href="qgraphicsscene.html#dragMoveEvent">dragMoveEvent</a>(),
and <a href="qgraphicsscene.html#dropEvent">dropEvent</a>().</p>
<h3 class="fn"><a name="dragMoveEvent" />QGraphicsScene.dragMoveEvent (<i>self</i>, <a href="qgraphicsscenedragdropevent.html">QGraphicsSceneDragDropEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>event</i>, can be reimplemented
in a subclass to receive drag move events for the scene.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#dragMoveEvent">QGraphicsItem.dragMoveEvent</a>(),
<a href="qgraphicsscene.html#dragEnterEvent">dragEnterEvent</a>(),
<a href="qgraphicsscene.html#dragLeaveEvent">dragLeaveEvent</a>(),
and <a href="qgraphicsscene.html#dropEvent">dropEvent</a>().</p>
<h3 class="fn"><a name="drawBackground" />QGraphicsScene.drawBackground (<i>self</i>, <a href="qpainter.html">QPainter</a> <i>painter</i>, <a href="qrectf.html">QRectF</a> <i>rect</i>)</h3><p>Draws the background of the scene using <i>painter</i>, before
any items and the foreground are drawn. Reimplement this function
to provide a custom background for the scene.</p>
<p>All painting is done in <i>scene</i> coordinates. The
<i>rect</i> parameter is the exposed rectangle.</p>
<p>If all you want is to define a color, texture, or gradient for
the background, you can call <a href="qgraphicsscene.html#backgroundBrush-prop">setBackgroundBrush</a>()
instead.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#drawForeground">drawForeground</a>() and
<a class="obsolete" href="qgraphicsscene-obsolete.html#drawItems">drawItems</a>().</p>
<h3 class="fn"><a name="drawForeground" />QGraphicsScene.drawForeground (<i>self</i>, <a href="qpainter.html">QPainter</a> <i>painter</i>, <a href="qrectf.html">QRectF</a> <i>rect</i>)</h3><p>Draws the foreground of the scene using <i>painter</i>, after
the background and all items have been drawn. Reimplement this
function to provide a custom foreground for the scene.</p>
<p>All painting is done in <i>scene</i> coordinates. The
<i>rect</i> parameter is the exposed rectangle.</p>
<p>If all you want is to define a color, texture or gradient for
the foreground, you can call <a href="qgraphicsscene.html#foregroundBrush-prop">setForegroundBrush</a>()
instead.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#drawBackground">drawBackground</a>() and
<a class="obsolete" href="qgraphicsscene-obsolete.html#drawItems">drawItems</a>().</p>
<h3 class="fn"><a name="drawItems" />QGraphicsScene.drawItems (<i>self</i>, <a href="qpainter.html">QPainter</a> <i>painter</i>, list-of-QGraphicsItem <i>items</i>, list-of-QStyleOptionGraphicsItem <i>options</i>, <a href="qwidget.html">QWidget</a> <i>widget</i> = None)</h3><h3 class="fn"><a name="dropEvent" />QGraphicsScene.dropEvent (<i>self</i>, <a href="qgraphicsscenedragdropevent.html">QGraphicsSceneDragDropEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>event</i>, can be reimplemented
in a subclass to receive drop events for the scene.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#dropEvent">QGraphicsItem.dropEvent</a>(),
<a href="qgraphicsscene.html#dragEnterEvent">dragEnterEvent</a>(),
<a href="qgraphicsscene.html#dragMoveEvent">dragMoveEvent</a>(),
and <a href="qgraphicsscene.html#dragLeaveEvent">dragLeaveEvent</a>().</p>
<h3 class="fn"><a name="event" />bool QGraphicsScene.event (<i>self</i>, <a href="qevent.html">QEvent</a> <i>event</i>)</h3><p>Reimplemented from <a href="qobject.html#event">QObject.event</a>().</p>
<p>Processes the event <i>event</i>, and dispatches it to the
respective event handlers.</p>
<p>In addition to calling the convenience event handlers, this
function is responsible for converting mouse move events to hover
events for when there is no mouse grabber item. Hover events are
delivered directly to items; there is no convenience function for
them.</p>
<p>Unlike <a href="qwidget.html">QWidget</a>, <a href="qgraphicsscene.html">QGraphicsScene</a> does not have the
convenience functions <a href="qwidget.html#enterEvent">enterEvent()</a> and <a href="qwidget.html#leaveEvent">leaveEvent()</a>. Use this function to
obtain those events instead.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#contextMenuEvent">contextMenuEvent</a>(),
<a href="qgraphicsscene.html#keyPressEvent">keyPressEvent</a>(),
<a href="qgraphicsscene.html#keyReleaseEvent">keyReleaseEvent</a>(),
<a href="qgraphicsscene.html#mousePressEvent">mousePressEvent</a>(),
<a href="qgraphicsscene.html#mouseMoveEvent">mouseMoveEvent</a>(),
<a href="qgraphicsscene.html#mouseReleaseEvent">mouseReleaseEvent</a>(),
<a href="qgraphicsscene.html#mouseDoubleClickEvent">mouseDoubleClickEvent</a>(),
<a href="qgraphicsscene.html#focusInEvent">focusInEvent</a>(), and
<a href="qgraphicsscene.html#focusOutEvent">focusOutEvent</a>().</p>
<h3 class="fn"><a name="eventFilter" />bool QGraphicsScene.eventFilter (<i>self</i>, <a href="qobject.html">QObject</a> <i>watched</i>, <a href="qevent.html">QEvent</a> <i>event</i>)</h3><p>Reimplemented from <a href="qobject.html#eventFilter">QObject.eventFilter</a>().</p>
<p><a href="qgraphicsscene.html">QGraphicsScene</a> filters
<a href="qapplication.html">QApplication</a>'s events to detect
palette and font changes.</p>
<h3 class="fn"><a name="focusInEvent" />QGraphicsScene.focusInEvent (<i>self</i>, <a href="qfocusevent.html">QFocusEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>focusEvent</i>, can be
reimplemented in a subclass to receive focus in events.</p>
<p>The default implementation sets focus on the scene, and then on
the last focus item.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#focusOutEvent">QGraphicsItem.focusOutEvent</a>().</p>
<h3 class="fn"><a name="focusItem" /><a href="qgraphicsitem.html">QGraphicsItem</a> QGraphicsScene.focusItem (<i>self</i>)</h3><p>When the scene is active, this functions returns the scene's
current focus item, or 0 if no item currently has focus. When the
scene is inactive, this functions returns the item that will gain
input focus when the scene becomes active.</p>
<p>The focus item receives keyboard input when the scene receives a
key event.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setFocusItem">setFocusItem</a>(), <a href="qgraphicsitem.html#hasFocus">QGraphicsItem.hasFocus</a>(), and
<a href="qgraphicsscene.html#isActive">isActive</a>().</p>
<h3 class="fn"><a name="focusNextPrevChild" />bool QGraphicsScene.focusNextPrevChild (<i>self</i>, bool <i>next</i>)</h3><p>Finds a new widget to give the keyboard focus to, as appropriate
for Tab and Shift+Tab, and returns true if it can find a new
widget, or false if it cannot. If <i>next</i> is true, this
function searches forward; if <i>next</i> is false, it searches
backward.</p>
<p>You can reimplement this function in a subclass of <a href="qgraphicsscene.html">QGraphicsScene</a> to provide fine-grained
control over how tab focus passes inside your scene. The default
implementation is based on the tab focus chain defined by <a href="qgraphicswidget.html#setTabOrder">QGraphicsWidget.setTabOrder</a>().</p>
<p>This function was introduced in Qt 4.4.</p>
<h3 class="fn"><a name="focusOutEvent" />QGraphicsScene.focusOutEvent (<i>self</i>, <a href="qfocusevent.html">QFocusEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>focusEvent</i>, can be
reimplemented in a subclass to receive focus out events.</p>
<p>The default implementation removes focus from any focus item,
then removes focus from the scene.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#focusInEvent">QGraphicsItem.focusInEvent</a>().</p>
<h3 class="fn"><a name="font" /><a href="qfont.html">QFont</a> QGraphicsScene.font (<i>self</i>)</h3><h3 class="fn"><a name="foregroundBrush" /><a href="qbrush.html">QBrush</a> QGraphicsScene.foregroundBrush (<i>self</i>)</h3><h3 class="fn"><a name="hasFocus" />bool QGraphicsScene.hasFocus (<i>self</i>)</h3><p>Returns true if the scene has focus; otherwise returns false. If
the scene has focus, it will will forward key events from <a href="qkeyevent.html">QKeyEvent</a> to any item that has focus.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setFocus">setFocus</a>() and <a href="qgraphicsscene.html#setFocusItem">setFocusItem</a>().</p>
<h3 class="fn"><a name="height" />float QGraphicsScene.height (<i>self</i>)</h3><p>This convenience function is equivalent to calling
<tt>sceneRect().height()</tt>.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#width">width</a>().</p>
<h3 class="fn"><a name="helpEvent" />QGraphicsScene.helpEvent (<i>self</i>, <a href="qgraphicsscenehelpevent.html">QGraphicsSceneHelpEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>helpEvent</i>, can be
reimplemented in a subclass to receive help events. The events are
of type <a href="qevent.html#Type-enum">QEvent.ToolTip</a>, which
are created when a tooltip is requested.</p>
<p>The default implementation shows the tooltip of the topmost
item, i.e., the item with the highest z-value, at the mouse cursor
position. If no item has a tooltip set, this function does
nothing.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#toolTip">QGraphicsItem.toolTip</a>() and
<a href="qgraphicsscenehelpevent.html">QGraphicsSceneHelpEvent</a>.</p>
<h3 class="fn"><a name="inputMethodEvent" />QGraphicsScene.inputMethodEvent (<i>self</i>, <a href="qinputmethodevent.html">QInputMethodEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>event</i>, can be reimplemented
in a subclass to receive input method events for the scene.</p>
<p>The default implementation forwards the event to the <a href="qgraphicsscene.html#focusItem">focusItem</a>(). If no item
currently has focus or the current focus item does not accept input
methods, this function does nothing.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#inputMethodEvent">QGraphicsItem.inputMethodEvent</a>().</p>
<h3 class="fn"><a name="inputMethodQuery" />QVariant QGraphicsScene.inputMethodQuery (<i>self</i>, <a href="qt.html#InputMethodQuery-enum">Qt.InputMethodQuery</a> <i>query</i>)</h3><p>This method is used by input methods to query a set of
properties of the scene to be able to support complex input method
operations as support for surrounding text and reconversions.</p>
<p>The <i>query</i> parameter specifies which property is
queried.</p>
<p><b>See also</b> <a href="qwidget.html#inputMethodQuery">QWidget.inputMethodQuery</a>().</p>
<h3 class="fn"><a name="invalidate" />QGraphicsScene.invalidate (<i>self</i>, <a href="qrectf.html">QRectF</a> <i>rect</i> = QRectF(), <a href="qgraphicsscene-scenelayers.html">SceneLayers</a> <i>layers</i> = QGraphicsScene.AllLayers)</h3><p>This method is also a Qt slot with the C++ signature <tt>void invalidate(const QRectF& = QRectF(),QGraphicsScene::SceneLayers = QGraphicsScene.AllLayers)</tt>.</p><p>Invalidates and schedules a redraw of the <i>layers</i> in
<i>rect</i> on the scene. Any cached content in <i>layers</i> is
unconditionally invalidated and redrawn.</p>
<p>You can use this function overload to notify <a href="qgraphicsscene.html">QGraphicsScene</a> of changes to the
background or the foreground of the scene. This function is
commonly used for scenes with tile-based backgrounds to notify
changes when <a href="qgraphicsview.html">QGraphicsView</a> has
enabled <a href="qgraphicsview.html#CacheModeFlag-enum">CacheBackground</a>.</p>
<p>Example:</p>
<pre class="cpp">
<span class="type"><a href="qrectf.html">QRectF</a></span> TileScene<span class="operator">.</span>rectForTile(<span class="type">int</span> x<span class="operator">,</span> <span class="type">int</span> y) <span class="keyword">const</span>
{
<span class="comment">// Return the rectangle for the tile at position (x, y).</span>
<span class="keyword">return</span> <span class="type"><a href="qrectf.html">QRectF</a></span>(x <span class="operator">*</span> tileWidth<span class="operator">,</span> y <span class="operator">*</span> tileHeight<span class="operator">,</span> tileWidth<span class="operator">,</span> tileHeight);
}
<span class="type">void</span> TileScene<span class="operator">.</span>setTile(<span class="type">int</span> x<span class="operator">,</span> <span class="type">int</span> y<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="qpixmap.html">QPixmap</a></span> <span class="operator">&</span>pixmap)
{
<span class="comment">// Sets or replaces the tile at position (x, y) with pixmap.</span>
<span class="keyword">if</span> (x <span class="operator">></span><span class="operator">=</span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> x <span class="operator"><</span> numTilesH <span class="operator">&</span><span class="operator">&</span> y <span class="operator">></span><span class="operator">=</span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> y <span class="operator"><</span> numTilesV) {
tiles<span class="operator">[</span>y<span class="operator">]</span><span class="operator">[</span>x<span class="operator">]</span> <span class="operator">=</span> pixmap;
invalidate(rectForTile(x<span class="operator">,</span> y)<span class="operator">,</span> BackgroundLayer);
}
}
<span class="type">void</span> TileScene<span class="operator">.</span>drawBackground(<span class="type"><a href="qpainter.html">QPainter</a></span> <span class="operator">*</span>painter<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="qrectf.html">QRectF</a></span> <span class="operator">&</span>exposed)
{
<span class="comment">// Draws all tiles that intersect the exposed area.</span>
<span class="keyword">for</span> (<span class="type">int</span> y <span class="operator">=</span> <span class="number">0</span>; y <span class="operator"><</span> numTilesV; <span class="operator">+</span><span class="operator">+</span>y) {
<span class="keyword">for</span> (<span class="type">int</span> x <span class="operator">=</span> <span class="number">0</span>; x <span class="operator"><</span> numTilesH; <span class="operator">+</span><span class="operator">+</span>x) {
<span class="type"><a href="qrectf.html">QRectF</a></span> rect <span class="operator">=</span> rectForTile(x<span class="operator">,</span> y);
<span class="keyword">if</span> (exposed<span class="operator">.</span>intersects(rect))
painter<span class="operator">-</span><span class="operator">></span>drawPixmap(rect<span class="operator">.</span>topLeft()<span class="operator">,</span> tiles<span class="operator">[</span>y<span class="operator">]</span><span class="operator">[</span>x<span class="operator">]</span>);
}
}
}
</pre>
<p>Note that <a href="qgraphicsview.html">QGraphicsView</a>
currently supports background caching only (see <a href="qgraphicsview.html#CacheModeFlag-enum">QGraphicsView.CacheBackground</a>).
This function is equivalent to calling <a href="qgraphicsscene.html#update">update</a>() if any layer but <a href="qgraphicsscene.html#SceneLayer-enum">BackgroundLayer</a> is
passed.</p>
<p><b>See also</b> <a href="qgraphicsview.html#resetCachedContent">QGraphicsView.resetCachedContent</a>().</p>
<h3 class="fn"><a name="invalidate-2" />QGraphicsScene.invalidate (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, <a href="qgraphicsscene-scenelayers.html">SceneLayers</a> <i>layers</i> = QGraphicsScene.AllLayers)</h3><p>This is an overloaded function.</p>
<p>This convenience function is equivalent to calling
invalidate(<a href="qrectf.html">QRectF</a>(<i>x</i>, <i>y</i>,
<i>w</i>, <i>h</i>), <i>layers</i>);</p>
<p>This function was introduced in Qt 4.3.</p>
<h3 class="fn"><a name="isActive" />bool QGraphicsScene.isActive (<i>self</i>)</h3><p>Returns true if the scene is active (e.g., it's viewed by at
least one <a href="qgraphicsview.html">QGraphicsView</a> that is
active); otherwise returns false.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#isActive">QGraphicsItem.isActive</a>() and
<a href="qwidget.html#isActiveWindow-prop">QWidget.isActiveWindow</a>().</p>
<h3 class="fn"><a name="isSortCacheEnabled" />bool QGraphicsScene.isSortCacheEnabled (<i>self</i>)</h3><h3 class="fn"><a name="itemAt" /><a href="qgraphicsitem.html">QGraphicsItem</a> QGraphicsScene.itemAt (<i>self</i>, <a href="qpointf.html">QPointF</a> <i>pos</i>)</h3><p>Returns the topmost visible item at the specified
<i>position</i>, or 0 if there are no items at this position.</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#items">items</a>(),
<a href="qgraphicsscene.html#collidingItems">collidingItems</a>(),
and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="itemAt-2" /><a href="qgraphicsitem.html">QGraphicsItem</a> QGraphicsScene.itemAt (<i>self</i>, float <i>x</i>, float <i>y</i>)</h3><h3 class="fn"><a name="itemAt-3" /><a href="qgraphicsitem.html">QGraphicsItem</a> QGraphicsScene.itemAt (<i>self</i>, <a href="qpointf.html">QPointF</a> <i>pos</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i>)</h3><p>This is an overloaded function.</p>
<p>Returns the topmost item at the position specified by (<i>x</i>,
<i>y</i>), or 0 if there are no items at this position.</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>This convenience function is equivalent to calling
<tt>itemAt(QPointF(x, y), deviceTransform)</tt>.</p>
<p>This function was introduced in Qt 4.6.</p>
<h3 class="fn"><a name="itemAt-4" /><a href="qgraphicsitem.html">QGraphicsItem</a> QGraphicsScene.itemAt (<i>self</i>, float <i>x</i>, float <i>y</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i>)</h3><h3 class="fn"><a name="itemIndexMethod" /><a href="qgraphicsscene.html#ItemIndexMethod-enum">ItemIndexMethod</a> QGraphicsScene.itemIndexMethod (<i>self</i>)</h3><h3 class="fn"><a name="items" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>)</h3><p>Returns a list of all items in the scene in descending stacking
order.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addItem">addItem</a>(), <a href="qgraphicsscene.html#removeItem">removeItem</a>(), and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="items-2" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qt.html#SortOrder-enum">Qt.SortOrder</a> <i>order</i>)</h3><p>Returns an ordered list of all items on the scene. <i>order</i>
decides the stacking order.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addItem">addItem</a>(), <a href="qgraphicsscene.html#removeItem">removeItem</a>(), and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="items-3" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qpointf.html">QPointF</a> <i>pos</i>)</h3><p>Returns all visible items that, depending on <i>mode</i>, are at
the specified <i>pos</i> in a list sorted using <i>order</i>.</p>
<p>The default value for <i>mode</i> is <a href="qt.html#ItemSelectionMode-enum">Qt.IntersectsItemShape</a>; all
items whose exact shape intersects with <i>pos</i> are
returned.</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#itemAt">itemAt</a>() and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="items-4" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qpointf.html">QPointF</a> <i>pos</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i>, <a href="qt.html#SortOrder-enum">Qt.SortOrder</a> <i>order</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i> = QTransform())</h3><h3 class="fn"><a name="items-5" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qrectf.html">QRectF</a> <i>rectangle</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i> = Qt.IntersectsItemShape)</h3><h3 class="fn"><a name="items-6" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qrectf.html">QRectF</a> <i>rect</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i>, <a href="qt.html#SortOrder-enum">Qt.SortOrder</a> <i>order</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i> = QTransform())</h3><h3 class="fn"><a name="items-7" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qpolygonf.html">QPolygonF</a> <i>polygon</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i> = Qt.IntersectsItemShape)</h3><p>This is an overloaded function.</p>
<p>Returns all visible items that, depending on <i>mode</i>, are
either inside or intersect with the rectangle defined by <i>x</i>,
<i>y</i>, <i>w</i> and <i>h</i>, in a list sorted using
<i>order</i>.</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>This function was introduced in Qt 4.6.</p>
<h3 class="fn"><a name="items-8" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qpolygonf.html">QPolygonF</a> <i>polygon</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i>, <a href="qt.html#SortOrder-enum">Qt.SortOrder</a> <i>order</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i> = QTransform())</h3><h3 class="fn"><a name="items-9" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qpainterpath.html">QPainterPath</a> <i>path</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i> = Qt.IntersectsItemShape)</h3><h3 class="fn"><a name="items-10" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, <a href="qpainterpath.html">QPainterPath</a> <i>path</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i>, <a href="qt.html#SortOrder-enum">Qt.SortOrder</a> <i>order</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i> = QTransform())</h3><p>This is an overloaded function.</p>
<p>Returns all visible items that, depending on <i>mode</i>, are
either inside or intersect with the specified <i>rect</i> and
return a list sorted using <i>order</i>.</p>
<p>The default value for <i>mode</i> is <a href="qt.html#ItemSelectionMode-enum">Qt.IntersectsItemShape</a>; all
items whose exact shape intersects with or is contained by
<i>rect</i> are returned.</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#itemAt">itemAt</a>() and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="items-11" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i> = Qt.IntersectsItemShape)</h3><p>This is an overloaded function.</p>
<p>Returns all visible items that, depending on <i>mode</i>, are
either inside or intersect with the specified <i>polygon</i> and
return a list sorted using <i>order</i>.</p>
<p>The default value for <i>mode</i> is <a href="qt.html#ItemSelectionMode-enum">Qt.IntersectsItemShape</a>; all
items whose exact shape intersects with or is contained by
<i>polygon</i> are returned.</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#itemAt">itemAt</a>() and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="items-12" />list-of-QGraphicsItem QGraphicsScene.items (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i>, <a href="qt.html#SortOrder-enum">Qt.SortOrder</a> <i>order</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i> = QTransform())</h3><p>This is an overloaded function.</p>
<p>Returns all visible items that, depending on <i>mode</i>, are
either inside or intersect with the specified <i>path</i> and
return a list sorted using <i>order</i>.</p>
<p>The default value for <i>mode</i> is <a href="qt.html#ItemSelectionMode-enum">Qt.IntersectsItemShape</a>; all
items whose exact shape intersects with or is contained by
<i>path</i> are returned.</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#itemAt">itemAt</a>() and <a href="qgraphicsitem.html#sorting">Sorting</a>.</p>
<h3 class="fn"><a name="itemsBoundingRect" /><a href="qrectf.html">QRectF</a> QGraphicsScene.itemsBoundingRect (<i>self</i>)</h3><p>Calculates and returns the bounding rect of all items on the
scene. This function works by iterating over all items, and because
if this, it can be slow for large scenes.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#sceneRect-prop">sceneRect</a>().</p>
<h3 class="fn"><a name="keyPressEvent" />QGraphicsScene.keyPressEvent (<i>self</i>, <a href="qkeyevent.html">QKeyEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>keyEvent</i>, can be
reimplemented in a subclass to receive keypress events. The default
implementation forwards the event to current focus item.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#keyPressEvent">QGraphicsItem.keyPressEvent</a>()
and <a href="qgraphicsscene.html#focusItem">focusItem</a>().</p>
<h3 class="fn"><a name="keyReleaseEvent" />QGraphicsScene.keyReleaseEvent (<i>self</i>, <a href="qkeyevent.html">QKeyEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>keyEvent</i>, can be
reimplemented in a subclass to receive key release events. The
default implementation forwards the event to current focus
item.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#keyReleaseEvent">QGraphicsItem.keyReleaseEvent</a>()
and <a href="qgraphicsscene.html#focusItem">focusItem</a>().</p>
<h3 class="fn"><a name="mouseDoubleClickEvent" />QGraphicsScene.mouseDoubleClickEvent (<i>self</i>, <a href="qgraphicsscenemouseevent.html">QGraphicsSceneMouseEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>mouseEvent</i>, can be
reimplemented in a subclass to receive mouse doubleclick events for
the scene.</p>
<p>If someone doubleclicks on the scene, the scene will first
receive a mouse press event, followed by a release event (i.e., a
click), then a doubleclick event, and finally a release event. If
the doubleclick event is delivered to a different item than the one
that received the first press and release, it will be delivered as
a press event. However, tripleclick events are not delivered as
doubleclick events in this case.</p>
<p>The default implementation is similar to <a href="qgraphicsscene.html#mousePressEvent">mousePressEvent</a>().</p>
<p><b>See also</b> <a href="qgraphicsitem.html#mousePressEvent">QGraphicsItem.mousePressEvent</a>(),
<a href="qgraphicsitem.html#mouseMoveEvent">QGraphicsItem.mouseMoveEvent</a>(),
<a href="qgraphicsitem.html#mouseReleaseEvent">QGraphicsItem.mouseReleaseEvent</a>(),
and <a href="qgraphicsitem.html#setAcceptedMouseButtons">QGraphicsItem.setAcceptedMouseButtons</a>().</p>
<h3 class="fn"><a name="mouseGrabberItem" /><a href="qgraphicsitem.html">QGraphicsItem</a> QGraphicsScene.mouseGrabberItem (<i>self</i>)</h3><p>Returns the current mouse grabber item, or 0 if no item is
currently grabbing the mouse. The mouse grabber item is the item
that receives all mouse events sent to the scene.</p>
<p>An item becomes a mouse grabber when it receives and accepts a
mouse press event, and it stays the mouse grabber until either of
the following events occur:</p>
<ul>
<li>If the item receives a mouse release event when there are no
other buttons pressed, it loses the mouse grab.</li>
<li>If the item becomes invisible (i.e., someone calls
<tt>item->setVisible(false)</tt>), or if it becomes disabled
(i.e., someone calls <tt>item->setEnabled(false)</tt>), it loses
the mouse grab.</li>
<li>If the item is removed from the scene, it loses the mouse
grab.</li>
</ul>
<p>If the item loses its mouse grab, the scene will ignore all
mouse events until a new item grabs the mouse (i.e., until a new
item receives a mouse press event).</p>
<h3 class="fn"><a name="mouseMoveEvent" />QGraphicsScene.mouseMoveEvent (<i>self</i>, <a href="qgraphicsscenemouseevent.html">QGraphicsSceneMouseEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>mouseEvent</i>, can be
reimplemented in a subclass to receive mouse move events for the
scene.</p>
<p>The default implementation depends on the mouse grabber state.
If there is a mouse grabber item, the event is sent to the mouse
grabber. If there are any items that accept hover events at the
current position, the event is translated into a hover event and
accepted; otherwise it's ignored.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#mousePressEvent">QGraphicsItem.mousePressEvent</a>(),
<a href="qgraphicsitem.html#mouseReleaseEvent">QGraphicsItem.mouseReleaseEvent</a>(),
<a href="qgraphicsitem.html#mouseDoubleClickEvent">QGraphicsItem.mouseDoubleClickEvent</a>(),
and <a href="qgraphicsitem.html#setAcceptedMouseButtons">QGraphicsItem.setAcceptedMouseButtons</a>().</p>
<h3 class="fn"><a name="mousePressEvent" />QGraphicsScene.mousePressEvent (<i>self</i>, <a href="qgraphicsscenemouseevent.html">QGraphicsSceneMouseEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>mouseEvent</i>, can be
reimplemented in a subclass to receive mouse press events for the
scene.</p>
<p>The default implementation depends on the state of the scene. If
there is a mouse grabber item, then the event is sent to the mouse
grabber. Otherwise, it is forwarded to the topmost item that
accepts mouse events at the scene position from the event, and that
item promptly becomes the mouse grabber item.</p>
<p>If there is no item at the given position on the scene, the
selection area is reset, any focus item loses its input focus, and
the event is then ignored.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#mousePressEvent">QGraphicsItem.mousePressEvent</a>()
and <a href="qgraphicsitem.html#setAcceptedMouseButtons">QGraphicsItem.setAcceptedMouseButtons</a>().</p>
<h3 class="fn"><a name="mouseReleaseEvent" />QGraphicsScene.mouseReleaseEvent (<i>self</i>, <a href="qgraphicsscenemouseevent.html">QGraphicsSceneMouseEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>mouseEvent</i>, can be
reimplemented in a subclass to receive mouse release events for the
scene.</p>
<p>The default implementation depends on the mouse grabber state.
If there is no mouse grabber, the event is ignored. Otherwise, if
there is a mouse grabber item, the event is sent to the mouse
grabber. If this mouse release represents the last pressed button
on the mouse, the mouse grabber item then loses the mouse grab.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#mousePressEvent">QGraphicsItem.mousePressEvent</a>(),
<a href="qgraphicsitem.html#mouseMoveEvent">QGraphicsItem.mouseMoveEvent</a>(),
<a href="qgraphicsitem.html#mouseDoubleClickEvent">QGraphicsItem.mouseDoubleClickEvent</a>(),
and <a href="qgraphicsitem.html#setAcceptedMouseButtons">QGraphicsItem.setAcceptedMouseButtons</a>().</p>
<h3 class="fn"><a name="palette" /><a href="qpalette.html">QPalette</a> QGraphicsScene.palette (<i>self</i>)</h3><h3 class="fn"><a name="removeItem" />QGraphicsScene.removeItem (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>item</i>)</h3><p>The <i>item</i> argument</p><p>Removes the item <i>item</i> and all its children from the
scene. The ownership of <i>item</i> is passed on to the caller
(i.e., <a href="qgraphicsscene.html">QGraphicsScene</a> will no
longer delete <i>item</i> when destroyed).</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addItem">addItem</a>().</p>
<h3 class="fn"><a name="render" />QGraphicsScene.render (<i>self</i>, <a href="qpainter.html">QPainter</a> <i>painter</i>, <a href="qrectf.html">QRectF</a> <i>target</i> = QRectF(), <a href="qrectf.html">QRectF</a> <i>source</i> = QRectF(), <a href="qt.html#AspectRatioMode-enum">Qt.AspectRatioMode</a> <i>mode</i> = Qt.KeepAspectRatio)</h3><p>Renders the <i>source</i> rect from scene into <i>target</i>,
using <i>painter</i>. This function is useful for capturing the
contents of the scene onto a paint device, such as a <a href="qimage.html">QImage</a> (e.g., to take a screenshot), or for
printing with <a href="qprinter.html">QPrinter</a>. For
example:</p>
<pre class="cpp">
<span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span> scene;
scene<span class="operator">.</span><a href="qgraphicsscene.html#addItem">addItem</a>(<span class="operator">.</span><span class="operator">.</span><span class="operator">.</span>
<span class="operator">.</span><span class="operator">.</span><span class="operator">.</span>
<span class="type"><a href="qprinter.html">QPrinter</a></span> printer(<span class="type"><a href="qprinter.html">QPrinter</a></span><span class="operator">.</span>HighResolution);
printer<span class="operator">.</span>setPaperSize(<span class="type"><a href="qprinter.html">QPrinter</a></span><span class="operator">.</span>A4);
<span class="type"><a href="qpainter.html">QPainter</a></span> painter(<span class="operator">&</span>printer);
scene<span class="operator">.</span>render(<span class="operator">&</span>painter);
</pre>
<p>If <i>source</i> is a null rect, this function will use <a href="qgraphicsscene.html#sceneRect-prop">sceneRect</a>() to determine
what to render. If <i>target</i> is a null rect, the dimensions of
<i>painter</i>'s paint device will be used.</p>
<p>The source rect contents will be transformed according to
<i>aspectRatioMode</i> to fit into the target rect. By default, the
aspect ratio is kept, and <i>source</i> is scaled to fit in
<i>target</i>.</p>
<p><b>See also</b> <a href="qgraphicsview.html#render">QGraphicsView.render</a>().</p>
<h3 class="fn"><a name="sceneRect" /><a href="qrectf.html">QRectF</a> QGraphicsScene.sceneRect (<i>self</i>)</h3><h3 class="fn"><a name="selectedItems" />list-of-QGraphicsItem QGraphicsScene.selectedItems (<i>self</i>)</h3><p>Returns a list of all currently selected items. The items are
returned in no particular order.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setSelectionArea">setSelectionArea</a>().</p>
<h3 class="fn"><a name="selectionArea" /><a href="qpainterpath.html">QPainterPath</a> QGraphicsScene.selectionArea (<i>self</i>)</h3><p>Returns the selection area that was previously set with <a href="qgraphicsscene.html#setSelectionArea">setSelectionArea</a>(), or
an empty <a href="qpainterpath.html">QPainterPath</a> if no
selection area has been set.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setSelectionArea">setSelectionArea</a>().</p>
<h3 class="fn"><a name="sendEvent" />bool QGraphicsScene.sendEvent (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>item</i>, <a href="qevent.html">QEvent</a> <i>event</i>)</h3><p>Sends event <i>event</i> to item <i>item</i> through possible
event filters.</p>
<p>The event is sent only if the item is enabled.</p>
<p>Returns <tt>false</tt> if the event was filtered or if the item
is disabled. Otherwise returns the value that was returned from the
event handler.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#sceneEvent">QGraphicsItem.sceneEvent</a>() and
<a href="qgraphicsitem.html#sceneEventFilter">QGraphicsItem.sceneEventFilter</a>().</p>
<h3 class="fn"><a name="setActivePanel" />QGraphicsScene.setActivePanel (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>item</i>)</h3><p>Activates <i>item</i>, which must be an item in this scene. You
can also pass 0 for <i>item</i>, in which case <a href="qgraphicsscene.html">QGraphicsScene</a> will deactivate any
currently active panel.</p>
<p>If the scene is currently inactive, <i>item</i> remains inactive
until the scene becomes active (or, ir <i>item</i> is 0, no item
will be activated).</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#activePanel">activePanel</a>(), <a href="qgraphicsscene.html#isActive">isActive</a>(), and <a href="qgraphicsitem.html#isActive">QGraphicsItem.isActive</a>().</p>
<h3 class="fn"><a name="setActiveWindow" />QGraphicsScene.setActiveWindow (<i>self</i>, <a href="qgraphicswidget.html">QGraphicsWidget</a> <i>widget</i>)</h3><p>Activates <i>widget</i>, which must be a widget in this scene.
You can also pass 0 for <i>widget</i>, in which case <a href="qgraphicsscene.html">QGraphicsScene</a> will deactivate any
currently active window.</p>
<p>This function was introduced in Qt 4.4.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#activeWindow">activeWindow</a>() and <a href="qgraphicswidget.html#isActiveWindow">QGraphicsWidget.isActiveWindow</a>().</p>
<h3 class="fn"><a name="setBackgroundBrush" />QGraphicsScene.setBackgroundBrush (<i>self</i>, <a href="qbrush.html">QBrush</a> <i>brush</i>)</h3><h3 class="fn"><a name="setBspTreeDepth" />QGraphicsScene.setBspTreeDepth (<i>self</i>, int <i>depth</i>)</h3><h3 class="fn"><a name="setFocus" />QGraphicsScene.setFocus (<i>self</i>, <a href="qt.html#FocusReason-enum">Qt.FocusReason</a> <i>focusReason</i> = Qt.OtherFocusReason)</h3><p>Sets focus on the scene by sending a <a href="qfocusevent.html">QFocusEvent</a> to the scene, passing
<i>focusReason</i> as the reason. If the scene regains focus after
having previously lost it while an item had focus, the last focus
item will receive focus with <i>focusReason</i> as the reason.</p>
<p>If the scene already has focus, this function does nothing.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#hasFocus">hasFocus</a>(), <a href="qgraphicsscene.html#clearFocus">clearFocus</a>(), and <a href="qgraphicsscene.html#setFocusItem">setFocusItem</a>().</p>
<h3 class="fn"><a name="setFocusItem" />QGraphicsScene.setFocusItem (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>item</i>, <a href="qt.html#FocusReason-enum">Qt.FocusReason</a> <i>focusReason</i> = Qt.OtherFocusReason)</h3><p>Sets the scene's focus item to <i>item</i>, with the focus
reason <i>focusReason</i>, after removing focus from any previous
item that may have had focus.</p>
<p>If <i>item</i> is 0, or if it either does not accept focus
(i.e., it does not have the <a href="qgraphicsitem.html#GraphicsItemFlag-enum">QGraphicsItem.ItemIsFocusable</a>
flag enabled), or is not visible or not enabled, this function only
removes focus from any previous focusitem.</p>
<p>If item is not 0, and the scene does not currently have focus
(i.e., <a href="qgraphicsscene.html#hasFocus">hasFocus</a>()
returns false), this function will call <a href="qgraphicsscene.html#setFocus">setFocus</a>() automatically.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#focusItem">focusItem</a>(), <a href="qgraphicsscene.html#hasFocus">hasFocus</a>(), and <a href="qgraphicsscene.html#setFocus">setFocus</a>().</p>
<h3 class="fn"><a name="setFont" />QGraphicsScene.setFont (<i>self</i>, <a href="qfont.html">QFont</a> <i>font</i>)</h3><h3 class="fn"><a name="setForegroundBrush" />QGraphicsScene.setForegroundBrush (<i>self</i>, <a href="qbrush.html">QBrush</a> <i>brush</i>)</h3><h3 class="fn"><a name="setItemIndexMethod" />QGraphicsScene.setItemIndexMethod (<i>self</i>, <a href="qgraphicsscene.html#ItemIndexMethod-enum">ItemIndexMethod</a> <i>method</i>)</h3><h3 class="fn"><a name="setPalette" />QGraphicsScene.setPalette (<i>self</i>, <a href="qpalette.html">QPalette</a> <i>palette</i>)</h3><h3 class="fn"><a name="setSceneRect" />QGraphicsScene.setSceneRect (<i>self</i>, <a href="qrectf.html">QRectF</a> <i>rect</i>)</h3><h3 class="fn"><a name="setSceneRect-2" />QGraphicsScene.setSceneRect (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>)</h3><h3 class="fn"><a name="setSelectionArea" />QGraphicsScene.setSelectionArea (<i>self</i>, <a href="qpainterpath.html">QPainterPath</a> <i>path</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i>)</h3><p>Sets the selection area to <i>path</i>. All items within this
area are immediately selected, and all items outside are
unselected. You can get the list of all selected items by calling
<a href="qgraphicsscene.html#selectedItems">selectedItems</a>().</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>For an item to be selected, it must be marked as
<i>selectable</i> (<a href="qgraphicsitem.html#GraphicsItemFlag-enum">QGraphicsItem.ItemIsSelectable</a>).</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#clearSelection">clearSelection</a>() and
<a href="qgraphicsscene.html#selectionArea">selectionArea</a>().</p>
<h3 class="fn"><a name="setSelectionArea-2" />QGraphicsScene.setSelectionArea (<i>self</i>, <a href="qpainterpath.html">QPainterPath</a> <i>path</i>)</h3><h3 class="fn"><a name="setSelectionArea-3" />QGraphicsScene.setSelectionArea (<i>self</i>, <a href="qpainterpath.html">QPainterPath</a> <i>path</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a>)</h3><h3 class="fn"><a name="setSelectionArea-4" />QGraphicsScene.setSelectionArea (<i>self</i>, <a href="qpainterpath.html">QPainterPath</a> <i>path</i>, <a href="qt.html#ItemSelectionMode-enum">Qt.ItemSelectionMode</a> <i>mode</i>, <a href="qtransform.html">QTransform</a> <i>deviceTransform</i>)</h3><p>This is an overloaded function.</p>
<p>Sets the selection area to <i>path</i> using <i>mode</i> to
determine if items are included in the selection area.</p>
<p><i>deviceTransform</i> is the transformation that applies to the
view, and needs to be provided if the scene contains items that
ignore transformations.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#clearSelection">clearSelection</a>() and
<a href="qgraphicsscene.html#selectionArea">selectionArea</a>().</p>
<h3 class="fn"><a name="setSortCacheEnabled" />QGraphicsScene.setSortCacheEnabled (<i>self</i>, bool <i>enabled</i>)</h3><h3 class="fn"><a name="setStickyFocus" />QGraphicsScene.setStickyFocus (<i>self</i>, bool <i>enabled</i>)</h3><h3 class="fn"><a name="setStyle" />QGraphicsScene.setStyle (<i>self</i>, <a href="qstyle.html">QStyle</a> <i>style</i>)</h3><p>The <i>style</i> argument has it's ownership transferred to Qt.</p><p>Sets or replaces the style of the scene to <i>style</i>, and
reparents the style to this scene. Any previously assigned style is
deleted. The scene's style defaults to <a href="qapplication.html#style">QApplication.style</a>(), and serves as
the default for all <a href="qgraphicswidget.html">QGraphicsWidget</a> items in the scene.</p>
<p>Changing the style, either directly by calling this function, or
indirectly by calling <a href="qapplication.html#setStyle">QApplication.setStyle</a>(), will
automatically update the style for all widgets in the scene that do
not have a style explicitly assigned to them.</p>
<p>If <i>style</i> is 0, <a href="qgraphicsscene.html">QGraphicsScene</a> will revert to <a href="qapplication.html#style">QApplication.style</a>().</p>
<p>This function was introduced in Qt 4.4.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#style">style</a>().</p>
<h3 class="fn"><a name="stickyFocus" />bool QGraphicsScene.stickyFocus (<i>self</i>)</h3><h3 class="fn"><a name="style" /><a href="qstyle.html">QStyle</a> QGraphicsScene.style (<i>self</i>)</h3><p>Returns the scene's style, or the same as <a href="qapplication.html#style">QApplication.style</a>() if the scene
has not been explicitly assigned a style.</p>
<p>This function was introduced in Qt 4.4.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setStyle">setStyle</a>().</p>
<h3 class="fn"><a name="update" />QGraphicsScene.update (<i>self</i>, <a href="qrectf.html">QRectF</a> <i>rect</i> = QRectF())</h3><p>This method is also a Qt slot with the C++ signature <tt>void update(const QRectF& = QRectF())</tt>.</p><p>Schedules a redraw of the area <i>rect</i> on the scene.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#sceneRect-prop">sceneRect</a>() and <a href="qgraphicsscene.html#changed">changed</a>().</p>
<h3 class="fn"><a name="update-2" />QGraphicsScene.update (<i>self</i>, float <i>x</i>, float <i>y</i>, float <i>w</i>, float <i>h</i>)</h3><p>This is an overloaded function.</p>
<p>This function is equivalent to calling update(<a href="qrectf.html">QRectF</a>(<i>x</i>, <i>y</i>, <i>w</i>,
<i>h</i>));</p>
<p>This function was introduced in Qt 4.3.</p>
<h3 class="fn"><a name="views" />list-of-QGraphicsView QGraphicsScene.views (<i>self</i>)</h3><p>Returns a list of all the views that display this scene.</p>
<p><b>See also</b> <a href="qgraphicsview.html#scene">QGraphicsView.scene</a>().</p>
<h3 class="fn"><a name="wheelEvent" />QGraphicsScene.wheelEvent (<i>self</i>, <a href="qgraphicsscenewheelevent.html">QGraphicsSceneWheelEvent</a> <i>event</i>)</h3><p>This event handler, for event <i>wheelEvent</i>, can be
reimplemented in a subclass to receive mouse wheel events for the
scene.</p>
<p>By default, the event is delivered to the topmost visible item
under the cursor. If ignored, the event propagates to the item
beneath, and again until the event is accepted, or it reaches the
scene. If no items accept the event, it is ignored.</p>
<p><b>See also</b> <a href="qgraphicsitem.html#wheelEvent">QGraphicsItem.wheelEvent</a>().</p>
<h3 class="fn"><a name="width" />float QGraphicsScene.width (<i>self</i>)</h3><p>This convenience function is equivalent to calling <a href="qgraphicsscene.html#sceneRect-prop">sceneRect</a>().width().</p>
<p><b>See also</b> <a href="qgraphicsscene.html#height">height</a>().</p>
<hr /><h2>Qt Signal Documentation</h2><h3 class="fn"><a name="changed" />void changed (const QList<QRectF>&)</h3><p>This is the default overload of this signal.</p><p>This signal is emitted by <a href="qgraphicsscene.html">QGraphicsScene</a> when control reaches the
event loop, if the scene content changes. The <i>region</i>
parameter contains a list of scene rectangles that indicate the
area that has been changed.</p>
<p><b>See also</b> <a href="qgraphicsview.html#updateScene">QGraphicsView.updateScene</a>().</p>
<h3 class="fn"><a name="sceneRectChanged" />void sceneRectChanged (const QRectF&)</h3><p>This is the default overload of this signal.</p><p>This signal is emitted by <a href="qgraphicsscene.html">QGraphicsScene</a> whenever the scene rect
changes. The <i>rect</i> parameter is the new scene rectangle.</p>
<p><b>See also</b> <a href="qgraphicsview.html#updateSceneRect">QGraphicsView.updateSceneRect</a>().</p>
<h3 class="fn"><a name="selectionChanged" />void selectionChanged ()</h3><p>This is the default overload of this signal.</p><p>This signal is emitted by <a href="qgraphicsscene.html">QGraphicsScene</a> whenever the selection
changes. You can call <a href="qgraphicsscene.html#selectedItems">selectedItems</a>() to get the
new list of selected items.</p>
<p>The selection changes whenever an item is selected or
unselected, a selection area is set, cleared or otherwise changed,
if a preselected item is added to the scene, or if a selected item
is removed from the scene.</p>
<p><a href="qgraphicsscene.html">QGraphicsScene</a> emits this
signal only once for group selection operations. For example, if
you set a selection area, select or unselect a <a href="qgraphicsitemgroup.html">QGraphicsItemGroup</a>, or if you add or
remove from the scene a parent item that contains several selected
items, selectionChanged() is emitted only once after the operation
has completed (instead of once for each item).</p>
<p>This function was introduced in Qt 4.3.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#setSelectionArea">setSelectionArea</a>(),
<a href="qgraphicsscene.html#selectedItems">selectedItems</a>(),
and <a href="qgraphicsitem.html#setSelected">QGraphicsItem.setSelected</a>().</p>
<address><hr /><div align="center"><table border="0" cellspacing="0" width="100%"><tr class="address"><td align="left" width="25%">PyQt 4.10.3 for X11</td><td align="center" width="50%">Copyright © <a href="http://www.riverbankcomputing.com">Riverbank Computing Ltd</a> and <a href="http://www.qtsoftware.com">Nokia</a> 2012</td><td align="right" width="25%">Qt 4.8.5</td></tr></table></div></address></body></html>
