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<td >Qt 5.9</td><td ><a href="qtwidgets-index.html">Qt Widgets</a></td><td ><a href="qtwidgets-module.html">C++ Classes</a></td><td >QGraphicsLayout</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right">Qt 5.9.4 Reference Documentation</td>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#reimplemented-public-functions">Reimplemented Public Functions</a></li>
<li class="level1"><a href="#protected-functions">Protected Functions</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
<li class="level2"><a href="#writing-a-custom-layout">Writing a Custom Layout</a></li>
<li class="level2"><a href="#activating-the-layout">Activating the Layout</a></li>
<li class="level2"><a href="#event-handling">Event Handling</a></li>
<li class="level2"><a href="#margin-handling">Margin Handling</a></li>
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<h1 class="title">QGraphicsLayout Class</h1>
<!-- $$$QGraphicsLayout-brief -->
<p>The <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> class provides the base class for all layouts in Graphics View. <a href="#details">More...</a></p>
<!-- @@@QGraphicsLayout -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QGraphicsLayout></span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += widgets</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 4.4</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherits:</td><td class="memItemRight bottomAlign"> <a href="qgraphicslayoutitem.html">QGraphicsLayoutItem</a></td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherited By:</td><td class="memItemRight bottomAlign"> <p><a href="qgraphicsanchorlayout.html">QGraphicsAnchorLayout</a>, <a href="qgraphicsgridlayout.html">QGraphicsGridLayout</a>, and <a href="qgraphicslinearlayout.html">QGraphicsLinearLayout</a></p>
</td></tr></table></div><ul>
<li><a href="qgraphicslayout-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="public-functions"></a>
<h2 id="public-functions">Public Functions</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#QGraphicsLayout">QGraphicsLayout</a></b>(QGraphicsLayoutItem *<i>parent</i> = Q_NULLPTR)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#dtor.QGraphicsLayout">~QGraphicsLayout</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#activate">activate</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual int </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#count">count</a></b>() const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#invalidate">invalidate</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#isActivated">isActivated</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QGraphicsLayoutItem *</td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#itemAt">itemAt</a></b>(int <i>i</i>) const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#removeAt">removeAt</a></b>(int <i>index</i>) = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#setContentsMargins">setContentsMargins</a></b>(qreal <i>left</i>, qreal <i>top</i>, qreal <i>right</i>, qreal <i>bottom</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#widgetEvent">widgetEvent</a></b>(QEvent *<i>e</i>)</td></tr>
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<a name="reimplemented-public-functions"></a>
<h2 id="reimplemented-public-functions">Reimplemented Public Functions</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#getContentsMargins">getContentsMargins</a></b>(qreal *<i>left</i>, qreal *<i>top</i>, qreal *<i>right</i>, qreal *<i>bottom</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#updateGeometry">updateGeometry</a></b>()</td></tr>
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<ul>
<li class="fn">35 public functions inherited from <a href="qgraphicslayoutitem.html#public-functions">QGraphicsLayoutItem</a></li>
</ul>
<a name="protected-functions"></a>
<h2 id="protected-functions">Protected Functions</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qgraphicslayout.html#addChildLayoutItem">addChildLayoutItem</a></b>(QGraphicsLayoutItem *<i>layoutItem</i>)</td></tr>
</table></div>
<ul>
<li class="fn">3 protected functions inherited from <a href="qgraphicslayoutitem.html#protected-functions">QGraphicsLayoutItem</a></li>
</ul>
<a name="details"></a>
<!-- $$$QGraphicsLayout-description -->
<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> class provides the base class for all layouts in Graphics View.</p>
<p><a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> is an abstract class that defines a virtual API for arranging <a href="graphicsview.html#qgraphicswidget">QGraphicsWidget</a> children and other <a href="qgraphicslayoutitem.html">QGraphicsLayoutItem</a> objects for a <a href="graphicsview.html#qgraphicswidget">QGraphicsWidget</a>. <a href="graphicsview.html#qgraphicswidget">QGraphicsWidget</a> assigns responsibility to a <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> through <a href="qgraphicswidget.html#setLayout">QGraphicsWidget::setLayout</a>(). As the widget is resized, the layout will automatically arrange the widget's children. <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> inherits <a href="qgraphicslayoutitem.html">QGraphicsLayoutItem</a>, so, it can be managed by any layout, including its own subclasses.</p>
<a name="writing-a-custom-layout"></a>
<h3 >Writing a Custom Layout</h3>
<p>You can use <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> as a base to write your own custom layout (e.g., a flowlayout), but it is more common to use one of its subclasses instead - <a href="qgraphicslinearlayout.html">QGraphicsLinearLayout</a> or <a href="qgraphicsgridlayout.html">QGraphicsGridLayout</a>. When creating a custom layout, the following functions must be reimplemented as a bare minimum:</p>
<div class="table"><table class="generic">
<thead><tr class="qt-style"><th >Function</th><th >Description</th></tr></thead>
<tr valign="top" class="odd"><td ><a href="qgraphicslayoutitem.html#setGeometry">QGraphicsLayoutItem::setGeometry</a>()</td><td >Notifies you when the geometry of the layout is set. You can store the geometry in your own layout class in a reimplementation of this function.</td></tr>
<tr valign="top" class="even"><td ><a href="qgraphicslayoutitem.html#sizeHint">QGraphicsLayoutItem::sizeHint</a>()</td><td >Returns the layout's size hints.</td></tr>
<tr valign="top" class="odd"><td ><a href="qgraphicslayout.html#count">QGraphicsLayout::count</a>()</td><td >Returns the number of items in your layout.</td></tr>
<tr valign="top" class="even"><td ><a href="qgraphicslayout.html#itemAt">QGraphicsLayout::itemAt</a>()</td><td >Returns a pointer to an item in your layout.</td></tr>
<tr valign="top" class="odd"><td ><a href="qgraphicslayout.html#removeAt">QGraphicsLayout::removeAt</a>()</td><td >Removes an item from your layout without destroying it.</td></tr>
</table></div>
<p>For more details on how to implement each function, refer to the individual function documentation.</p>
<p>Each layout defines its own API for arranging widgets and layout items. For example, with a grid layout, you require a row and a column index with optional row and column spans, alignment, spacing, and more. A linear layout, however, requires a single row or column index to position its items. For a grid layout, the order of insertion does not affect the layout in any way, but for a linear layout, the order is essential. When writing your own layout subclass, you are free to choose the API that best suits your layout.</p>
<p><a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> provides the <a href="qgraphicslayout.html#addChildLayoutItem">addChildLayoutItem</a>() convenience function to add layout items to a custom layout. The function will automatically reparent graphics items, if required.</p>
<a name="activating-the-layout"></a>
<h3 >Activating the Layout</h3>
<p>When the layout's geometry changes, <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> immediately rearranges all of its managed items by calling <a href="qgraphicslayoutitem.html#setGeometry">setGeometry</a>() on each item. This rearrangement is called <i>activating</i> the layout.</p>
<p><a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> updates its own geometry to match the <a href="qgraphicslayoutitem.html#contentsRect">contentsRect</a>() of the <a href="qgraphicslayoutitem.html">QGraphicsLayoutItem</a> it is managing. Thus, it will automatically rearrange all its items when the widget is resized. <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> caches the sizes of all its managed items to avoid calling <a href="qgraphicslayoutitem.html#setGeometry">setGeometry</a>() too often.</p>
<p><b>Note: </b>A <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> will have the same geometry as the <a href="qgraphicslayoutitem.html#contentsRect">contentsRect</a>() of the widget (not the layout) it is assigned to.</p><a name="activating-the-layout-implicitly"></a>
<h4 >Activating the Layout Implicitly</h4>
<p>The layout can be activated implicitly using one of two ways: by calling <a href="qgraphicslayout.html#activate">activate</a>() or by calling <a href="qgraphicslayout.html#invalidate">invalidate</a>(). Calling <a href="qgraphicslayout.html#activate">activate</a>() activates the layout immediately. In contrast, calling <a href="qgraphicslayout.html#invalidate">invalidate</a>() is delayed, as it posts a <a href="../qtcore/qevent.html#Type-enum">LayoutRequest</a> event to the managed widget. Due to event compression, the <a href="qgraphicslayout.html#activate">activate</a>() will only be called once after control has returned to the event loop. This is referred to as <i>invalidating</i> the layout. Invalidating the layout also invalidates any cached information. Also, the <a href="qgraphicslayout.html#invalidate">invalidate</a>() function is a virtual function. So, you can invalidate your own cache in a subclass of <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> by reimplementing this function.</p>
<a name="event-handling"></a>
<h3 >Event Handling</h3>
<p><a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> listens to events for the widget it manages through the virtual <a href="qgraphicslayout.html#widgetEvent">widgetEvent</a>() event handler. When the layout is assigned to a widget, all events delivered to the widget are first processed by <a href="qgraphicslayout.html#widgetEvent">widgetEvent</a>(). This allows the layout to be aware of any relevant state changes on the widget such as visibility changes or layout direction changes.</p>
<a name="margin-handling"></a>
<h3 >Margin Handling</h3>
<p>The margins of a <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> can be modified by reimplementing <a href="qgraphicslayout.html#setContentsMargins">setContentsMargins</a>() and <a href="qgraphicslayout.html#getContentsMargins">getContentsMargins</a>().</p>
</div>
<!-- @@@QGraphicsLayout -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$QGraphicsLayout[overload1]$$$QGraphicsLayoutQGraphicsLayoutItem* -->
<h3 class="fn" id="QGraphicsLayout"><a name="QGraphicsLayout"></a>QGraphicsLayout::<span class="name">QGraphicsLayout</span>(<span class="type"><a href="qgraphicslayoutitem.html#QGraphicsLayoutItem">QGraphicsLayoutItem</a></span> *<i>parent</i> = Q_NULLPTR)</h3>
<p>Contructs a <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> object.</p>
<p><i>parent</i> is passed to <a href="qgraphicslayoutitem.html">QGraphicsLayoutItem</a>'s constructor and the <a href="qgraphicslayoutitem.html">QGraphicsLayoutItem</a>'s <a href="qgraphicslayoutitem.html#isLayout">isLayout</a> argument is set to <i>true</i>.</p>
<p>If <i>parent</i> is a <a href="graphicsview.html#qgraphicswidget">QGraphicsWidget</a> the layout will be installed on that widget. (Note that installing a layout will delete the old one installed.)</p>
<!-- @@@QGraphicsLayout -->
<!-- $$$~QGraphicsLayout[overload1]$$$~QGraphicsLayout -->
<h3 class="fn" id="dtor.QGraphicsLayout"><a name="dtor.QGraphicsLayout"></a>QGraphicsLayout::<span class="name">~QGraphicsLayout</span>()</h3>
<p>Destroys the <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> object.</p>
<!-- @@@~QGraphicsLayout -->
<!-- $$$activate[overload1]$$$activate -->
<h3 class="fn" id="activate"><a name="activate"></a><span class="type">void</span> QGraphicsLayout::<span class="name">activate</span>()</h3>
<p>Activates the layout, causing all items in the layout to be immediately rearranged. This function is based on calling <a href="qgraphicslayout.html#count">count</a>() and <a href="qgraphicslayout.html#itemAt">itemAt</a>(), and then calling <a href="qgraphicslayoutitem.html#setGeometry">setGeometry</a>() on all items sequentially. When activated, the layout will adjust its geometry to its parent's <a href="qgraphicslayoutitem.html#contentsRect">contentsRect</a>(). The parent will then invalidate any layout of its own.</p>
<p>If called in sequence or recursively, e.g., by one of the arranged items in response to being resized, this function will do nothing.</p>
<p>Note that the layout is free to use geometry caching to optimize this process. To forcefully invalidate any such cache, you can call <a href="qgraphicslayout.html#invalidate">invalidate</a>() before calling activate().</p>
<p><b>See also </b><a href="qgraphicslayout.html#invalidate">invalidate</a>().</p>
<!-- @@@activate -->
<!-- $$$addChildLayoutItem[overload1]$$$addChildLayoutItemQGraphicsLayoutItem* -->
<h3 class="fn" id="addChildLayoutItem"><a name="addChildLayoutItem"></a><code>[protected] </code><span class="type">void</span> QGraphicsLayout::<span class="name">addChildLayoutItem</span>(<span class="type"><a href="qgraphicslayoutitem.html#QGraphicsLayoutItem">QGraphicsLayoutItem</a></span> *<i>layoutItem</i>)</h3>
<p>This function is a convenience function provided for custom layouts, and will go through all items in the layout and reparent their graphics items to the closest <a href="graphicsview.html#qgraphicswidget">QGraphicsWidget</a> ancestor of the layout.</p>
<p>If <i>layoutItem</i> is already in a different layout, it will be removed from that layout.</p>
<p>If custom layouts want special behaviour they can ignore to use this function, and implement their own behaviour.</p>
<p>This function was introduced in Qt 4.6.</p>
<p><b>See also </b><a href="qgraphicslayoutitem.html#graphicsItem">graphicsItem</a>().</p>
<!-- @@@addChildLayoutItem -->
<!-- $$$count[overload1]$$$count -->
<h3 class="fn" id="count"><a name="count"></a><code>[pure virtual] </code><span class="type">int</span> QGraphicsLayout::<span class="name">count</span>() const</h3>
<p>This pure virtual function must be reimplemented in a subclass of <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> to return the number of items in the layout.</p>
<p>The subclass is free to decide how to store the items.</p>
<p><b>See also </b><a href="qgraphicslayout.html#itemAt">itemAt</a>() and <a href="qgraphicslayout.html#removeAt">removeAt</a>().</p>
<!-- @@@count -->
<!-- $$$getContentsMargins[overload1]$$$getContentsMarginsqreal*qreal*qreal*qreal* -->
<h3 class="fn" id="getContentsMargins"><a name="getContentsMargins"></a><code>[virtual] </code><span class="type">void</span> QGraphicsLayout::<span class="name">getContentsMargins</span>(<span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> *<i>left</i>, <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> *<i>top</i>, <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> *<i>right</i>, <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> *<i>bottom</i>) const</h3>
<p>Reimplemented from <a href="qgraphicslayoutitem.html#getContentsMargins">QGraphicsLayoutItem::getContentsMargins</a>().</p>
<!-- @@@getContentsMargins -->
<!-- $$$invalidate[overload1]$$$invalidate -->
<h3 class="fn" id="invalidate"><a name="invalidate"></a><code>[virtual] </code><span class="type">void</span> QGraphicsLayout::<span class="name">invalidate</span>()</h3>
<p>Clears any cached geometry and size hint information in the layout, and posts a <a href="../qtcore/qevent.html#Type-enum">LayoutRequest</a> event to the managed parent <a href="qgraphicslayoutitem.html">QGraphicsLayoutItem</a>.</p>
<p><b>See also </b><a href="qgraphicslayout.html#activate">activate</a>() and <a href="qgraphicslayoutitem.html#setGeometry">setGeometry</a>().</p>
<!-- @@@invalidate -->
<!-- $$$isActivated[overload1]$$$isActivated -->
<h3 class="fn" id="isActivated"><a name="isActivated"></a><span class="type">bool</span> QGraphicsLayout::<span class="name">isActivated</span>() const</h3>
<p>Returns <code>true</code> if the layout is currently being activated; otherwise, returns <code>false</code>. If the layout is being activated, this means that it is currently in the process of rearranging its items (i.e., the <a href="qgraphicslayout.html#activate">activate</a>() function has been called, and has not yet returned).</p>
<p><b>See also </b><a href="qgraphicslayout.html#activate">activate</a>() and <a href="qgraphicslayout.html#invalidate">invalidate</a>().</p>
<!-- @@@isActivated -->
<!-- $$$itemAt[overload1]$$$itemAtint -->
<h3 class="fn" id="itemAt"><a name="itemAt"></a><code>[pure virtual] </code><span class="type"><a href="qgraphicslayoutitem.html#QGraphicsLayoutItem">QGraphicsLayoutItem</a></span> *QGraphicsLayout::<span class="name">itemAt</span>(<span class="type">int</span> <i>i</i>) const</h3>
<p>This pure virtual function must be reimplemented in a subclass of <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> to return a pointer to the item at index <i>i</i>. The reimplementation can assume that <i>i</i> is valid (i.e., it respects the value of <a href="qgraphicslayout.html#count">count</a>()). Together with <a href="qgraphicslayout.html#count">count</a>(), it is provided as a means of iterating over all items in a layout.</p>
<p>The subclass is free to decide how to store the items, and the visual arrangement does not have to be reflected through this function.</p>
<p><b>See also </b><a href="qgraphicslayout.html#count">count</a>() and <a href="qgraphicslayout.html#removeAt">removeAt</a>().</p>
<!-- @@@itemAt -->
<!-- $$$removeAt[overload1]$$$removeAtint -->
<h3 class="fn" id="removeAt"><a name="removeAt"></a><code>[pure virtual] </code><span class="type">void</span> QGraphicsLayout::<span class="name">removeAt</span>(<span class="type">int</span> <i>index</i>)</h3>
<p>This pure virtual function must be reimplemented in a subclass of <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> to remove the item at <i>index</i>. The reimplementation can assume that <i>index</i> is valid (i.e., it respects the value of <a href="qgraphicslayout.html#count">count</a>()).</p>
<p>The implementation must ensure that the <a href="qgraphicslayoutitem.html#parentLayoutItem">parentLayoutItem</a>() of the removed item does not point to this layout, since the item is considered to be removed from the layout hierarchy.</p>
<p>If the layout is to be reused between applications, we recommend that the layout deletes the item, but the graphics view framework does not depend on this.</p>
<p>The subclass is free to decide how to store the items.</p>
<p><b>See also </b><a href="qgraphicslayout.html#itemAt">itemAt</a>() and <a href="qgraphicslayout.html#count">count</a>().</p>
<!-- @@@removeAt -->
<!-- $$$setContentsMargins[overload1]$$$setContentsMarginsqrealqrealqrealqreal -->
<h3 class="fn" id="setContentsMargins"><a name="setContentsMargins"></a><span class="type">void</span> QGraphicsLayout::<span class="name">setContentsMargins</span>(<span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> <i>left</i>, <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> <i>top</i>, <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> <i>right</i>, <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> <i>bottom</i>)</h3>
<p>Sets the contents margins to <i>left</i>, <i>top</i>, <i>right</i> and <i>bottom</i>. The default contents margins for toplevel layouts are style dependent (by querying the pixelMetric for <a href="qstyle.html#PixelMetric-enum">QStyle::PM_LayoutLeftMargin</a>, <a href="qstyle.html#PixelMetric-enum">QStyle::PM_LayoutTopMargin</a>, <a href="qstyle.html#PixelMetric-enum">QStyle::PM_LayoutRightMargin</a> and <a href="qstyle.html#PixelMetric-enum">QStyle::PM_LayoutBottomMargin</a>).</p>
<p>For sublayouts the default margins are 0.</p>
<p>Changing the contents margins automatically invalidates the layout.</p>
<p><b>See also </b><a href="qgraphicslayout.html#invalidate">invalidate</a>().</p>
<!-- @@@setContentsMargins -->
<!-- $$$updateGeometry[overload1]$$$updateGeometry -->
<h3 class="fn" id="updateGeometry"><a name="updateGeometry"></a><code>[virtual] </code><span class="type">void</span> QGraphicsLayout::<span class="name">updateGeometry</span>()</h3>
<p>Reimplemented from <a href="qgraphicslayoutitem.html#updateGeometry">QGraphicsLayoutItem::updateGeometry</a>().</p>
<!-- @@@updateGeometry -->
<!-- $$$widgetEvent[overload1]$$$widgetEventQEvent* -->
<h3 class="fn" id="widgetEvent"><a name="widgetEvent"></a><code>[virtual] </code><span class="type">void</span> QGraphicsLayout::<span class="name">widgetEvent</span>(<span class="type"><a href="../qtcore/qevent.html">QEvent</a></span> *<i>e</i>)</h3>
<p>This virtual event handler receives all events for the managed widget. <a href="graphicsview.html#qgraphicslayout">QGraphicsLayout</a> uses this event handler to listen for layout related events such as geometry changes, layout changes or layout direction changes.</p>
<p><i>e</i> is a pointer to the event.</p>
<p>You can reimplement this event handler to track similar events for your own custom layout.</p>
<p><b>See also </b><a href="qgraphicswidget.html#event">QGraphicsWidget::event</a>() and <a href="qgraphicsitem.html#sceneEvent">QGraphicsItem::sceneEvent</a>().</p>
<!-- @@@widgetEvent -->
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