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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">QGraphicsItemGroup Class Reference<br /><sup><sup>[<a href="qtgui.html">QtGui</a> module]</sup></sup></h1><p>The QGraphicsItemGroup class provides a container that treats a
group of items as a single item. <a href="#details">More...</a></p>
<p>Inherits <a href="qgraphicsitem.html">QGraphicsItem</a>.</p><h3>Methods</h3><ul><li><div class="fn" /><b><a href="qgraphicsitemgroup.html#QGraphicsItemGroup">__init__</a></b> (<i>self</i>, QGraphicsItem <i>parent</i> = None, QGraphicsScene <i>scene</i> = None)</li><li><div class="fn" /><b><a href="qgraphicsitemgroup.html#addToGroup">addToGroup</a></b> (<i>self</i>, QGraphicsItem <i>item</i>)</li><li><div class="fn" />QRectF <b><a href="qgraphicsitemgroup.html#boundingRect">boundingRect</a></b> (<i>self</i>)</li><li><div class="fn" />bool <b><a href="qgraphicsitemgroup.html#isObscuredBy">isObscuredBy</a></b> (<i>self</i>, QGraphicsItem <i>item</i>)</li><li><div class="fn" />QPainterPath <b><a href="qgraphicsitemgroup.html#opaqueArea">opaqueArea</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qgraphicsitemgroup.html#paint">paint</a></b> (<i>self</i>, QPainter <i>painter</i>, QStyleOptionGraphicsItem <i>option</i>, QWidget <i>widget</i> = None)</li><li><div class="fn" /><b><a href="qgraphicsitemgroup.html#removeFromGroup">removeFromGroup</a></b> (<i>self</i>, QGraphicsItem <i>item</i>)</li><li><div class="fn" />int <b><a href="qgraphicsitemgroup.html#type">type</a></b> (<i>self</i>)</li></ul><a name="details" /><hr /><h2>Detailed Description</h2><p>The QGraphicsItemGroup class provides a container that treats a
group of items as a single item.</p>
<p>A QGraphicsItemGroup is a special type of compound item that
treats itself and all its children as one item (i.e., all events
and geometries for all children are merged together). It's common
to use item groups in presentation tools, when the user wants to
group several smaller items into one big item in order to simplify
moving and copying of items.</p>
<p>If all you want is to store items inside other items, you can
use any <a href="qgraphicsitem.html">QGraphicsItem</a> directly by
passing a suitable parent to <a href="qgraphicsitem.html#setParentItem">setParentItem</a>().</p>
<p>The <a href="qgraphicsitemgroup.html#boundingRect">boundingRect</a>() function
of QGraphicsItemGroup returns the bounding rectangle of all items
in the item group. QGraphicsItemGroup ignores the <a href="qgraphicsitem.html#GraphicsItemFlag-enum">ItemIgnoresTransformations</a>
flag on its children (i.e., with respect to the geometry of the
group item, the children are treated as if they were
transformable).</p>
<p>There are two ways to construct an item group. The easiest and
most common approach is to pass a list of items (e.g., all selected
items) to <a href="qgraphicsscene.html#createItemGroup">QGraphicsScene.createItemGroup</a>(),
which returns a new QGraphicsItemGroup item. The other approach is
to manually construct a QGraphicsItemGroup item, add it to the
scene calling <a href="qgraphicsscene.html#addItem">QGraphicsScene.addItem</a>(), and
then add items to the group manually, one at a time by calling
<a href="qgraphicsitemgroup.html#addToGroup">addToGroup</a>(). To
dismantle ("ungroup") an item group, you can either call <a href="qgraphicsscene.html#destroyItemGroup">QGraphicsScene.destroyItemGroup</a>(),
or you can manually remove all items from the group by calling
<a href="qgraphicsitemgroup.html#removeFromGroup">removeFromGroup</a>().</p>
<pre class="cpp">
<span class="comment">// Group all selected items together</span>
<span class="type">QGraphicsItemGroup</span> <span class="operator">*</span>group <span class="operator">=</span> scene<span class="operator">-</span><span class="operator">></span>createItemGroup(scene<span class="operator">-</span><span class="operator">></span>selecteditems());
<span class="comment">// Destroy the group, and delete the group item</span>
scene<span class="operator">-</span><span class="operator">></span>destroyItemGroup(group);
</pre>
<p>The operation of adding and removing items preserves the items'
scene-relative position and transformation, as opposed to calling
<a href="qgraphicsitem.html#setParentItem">setParentItem</a>(),
where only the child item's parent-relative position and
transformation are kept.</p>
<p>The addtoGroup() function reparents the target item to this item
group, keeping the item's position and transformation intact
relative to the scene. Visually, this means that items added via
<a href="qgraphicsitemgroup.html#addToGroup">addToGroup</a>() will
remain completely unchanged as a result of this operation,
regardless of the item or the group's current position or
transformation; although the item's position and matrix are likely
to change.</p>
<p>The <a href="qgraphicsitemgroup.html#removeFromGroup">removeFromGroup</a>()
function has similar semantics to <a href="qgraphicsitem.html#setParentItem">setParentItem</a>(); it
reparents the item to the parent item of the item group. As with
<a href="qgraphicsitemgroup.html#addToGroup">addToGroup</a>(), the
item's scene-relative position and transformation remain
intact.</p>
<hr /><h2>Method Documentation</h2><h3 class="fn"><a name="QGraphicsItemGroup" />QGraphicsItemGroup.__init__ (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>parent</i> = None, <a href="qgraphicsscene.html">QGraphicsScene</a> <i>scene</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>The <i>scene</i> argument, if not None, causes <i>self</i> to be owned by Qt instead of PyQt.</p><p>Constructs a <a href="qgraphicsitemgroup.html">QGraphicsItemGroup</a>. <i>parent</i> is
passed to <a href="qgraphicsitem.html">QGraphicsItem</a>'s
constructor.</p>
<p><b>See also</b> <a href="qgraphicsscene.html#addItem">QGraphicsScene.addItem</a>().</p>
<h3 class="fn"><a name="addToGroup" />QGraphicsItemGroup.addToGroup (<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 the given <i>item</i> and item's child items to this item
group. The item and child items will be reparented to this group,
but its position and transformation relative to the scene will stay
intact.</p>
<p><b>See also</b> <a href="qgraphicsitemgroup.html#removeFromGroup">removeFromGroup</a>() and
<a href="qgraphicsscene.html#createItemGroup">QGraphicsScene.createItemGroup</a>().</p>
<h3 class="fn"><a name="boundingRect" /><a href="qrectf.html">QRectF</a> QGraphicsItemGroup.boundingRect (<i>self</i>)</h3><p>Reimplemented from <a href="qgraphicsitem.html#boundingRect">QGraphicsItem.boundingRect</a>().</p>
<p>Returns the bounding rect of this group item, and all its
children.</p>
<h3 class="fn"><a name="isObscuredBy" />bool QGraphicsItemGroup.isObscuredBy (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>item</i>)</h3><p>Reimplemented from <a href="qgraphicsitem.html#isObscuredBy">QGraphicsItem.isObscuredBy</a>().</p>
<h3 class="fn"><a name="opaqueArea" /><a href="qpainterpath.html">QPainterPath</a> QGraphicsItemGroup.opaqueArea (<i>self</i>)</h3><p>Reimplemented from <a href="qgraphicsitem.html#opaqueArea">QGraphicsItem.opaqueArea</a>().</p>
<h3 class="fn"><a name="paint" />QGraphicsItemGroup.paint (<i>self</i>, <a href="qpainter.html">QPainter</a> <i>painter</i>, <a href="qstyleoptiongraphicsitem.html">QStyleOptionGraphicsItem</a> <i>option</i>, <a href="qwidget.html">QWidget</a> <i>widget</i> = None)</h3><p>Reimplemented from <a href="qgraphicsitem.html#paint">QGraphicsItem.paint</a>().</p>
<h3 class="fn"><a name="removeFromGroup" />QGraphicsItemGroup.removeFromGroup (<i>self</i>, <a href="qgraphicsitem.html">QGraphicsItem</a> <i>item</i>)</h3><p>Removes the specified <i>item</i> from this group. The item will
be reparented to this group's parent item, or to 0 if this group
has no parent. Its position and transformation relative to the
scene will stay intact.</p>
<p><b>See also</b> <a href="qgraphicsitemgroup.html#addToGroup">addToGroup</a>() and <a href="qgraphicsscene.html#destroyItemGroup">QGraphicsScene.destroyItemGroup</a>().</p>
<h3 class="fn"><a name="type" />int QGraphicsItemGroup.type (<i>self</i>)</h3><p>Reimplemented from <a href="qgraphicsitem.html#type">QGraphicsItem.type</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>
