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<td align="right" valign="top" width="230"><a href="http://www.trolltech.com"><img src="images/trolltech-logo.png" align="right" width="203" height="32" border="0" /></a></td></tr></table><h1 align="center">QRubberBand Class Reference<br /><sup><sup>[<a href="qtgui.html">QtGui</a> module]</sup></sup></h1>
<p>The QRubberBand class provides a rectangle or line that can indicate a selection or a boundary. <a href="#details">More...</a></p>
<pre> #include <QRubberBand></pre><p>Inherits <a href="qwidget.html">QWidget</a>.</p>
<ul>
<li><a href="qrubberband-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="public-types"></a>
<h3>Public Types</h3>
<ul>
<li><div class="fn"/>enum <b><a href="qrubberband.html#Shape-enum">Shape</a></b> { Line, Rectangle }</li>
</ul>
<a name="public-functions"></a>
<h3>Public Functions</h3>
<ul>
<li><div class="fn"/><b><a href="qrubberband.html#QRubberBand">QRubberBand</a></b> ( Shape <i>s</i>, QWidget * <i>p</i> = 0 )</li>
<li><div class="fn"/><b><a href="qrubberband.html#dtor.QRubberBand">~QRubberBand</a></b> ()</li>
<li><div class="fn"/>void <b><a href="qrubberband.html#move">move</a></b> ( int <i>x</i>, int <i>y</i> )</li>
<li><div class="fn"/>void <b><a href="qrubberband.html#move-2">move</a></b> ( const QPoint & <i>p</i> )</li>
<li><div class="fn"/>void <b><a href="qrubberband.html#resize">resize</a></b> ( int <i>width</i>, int <i>height</i> )</li>
<li><div class="fn"/>void <b><a href="qrubberband.html#resize-2">resize</a></b> ( const QSize & <i>size</i> )</li>
<li><div class="fn"/>void <b><a href="qrubberband.html#setGeometry">setGeometry</a></b> ( const QRect & <i>rect</i> )</li>
<li><div class="fn"/>void <b><a href="qrubberband.html#setGeometry-2">setGeometry</a></b> ( int <i>x</i>, int <i>y</i>, int <i>width</i>, int <i>height</i> )</li>
<li><div class="fn"/>Shape <b><a href="qrubberband.html#shape">shape</a></b> () const</li>
</ul>
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<li><div class="fn"/>195 public functions inherited from <a href="qwidget.html#public-functions">QWidget</a></li>
<li><div class="fn"/>29 public functions inherited from <a href="qobject.html#public-functions">QObject</a></li>
<li><div class="fn"/>12 public functions inherited from <a href="qpaintdevice.html#public-functions">QPaintDevice</a></li>
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<h3>Additional Inherited Members</h3>
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<li><div class="fn"/>55 properties inherited from <a href="qwidget.html#properties">QWidget</a></li>
<li><div class="fn"/>1 property inherited from <a href="qobject.html#properties">QObject</a></li>
<li><div class="fn"/>19 public slots inherited from <a href="qwidget.html#public-slots">QWidget</a></li>
<li><div class="fn"/>1 public slot inherited from <a href="qobject.html#public-slots">QObject</a></li>
<li><div class="fn"/>1 signal inherited from <a href="qwidget.html#signals">QWidget</a></li>
<li><div class="fn"/>1 signal inherited from <a href="qobject.html#signals">QObject</a></li>
<li><div class="fn"/>4 static public members inherited from <a href="qwidget.html#static-public-members">QWidget</a></li>
<li><div class="fn"/>5 static public members inherited from <a href="qobject.html#static-public-members">QObject</a></li>
<li><div class="fn"/>38 protected functions inherited from <a href="qwidget.html#protected-functions">QWidget</a></li>
<li><div class="fn"/>7 protected functions inherited from <a href="qobject.html#protected-functions">QObject</a></li>
<li><div class="fn"/>1 protected function inherited from <a href="qpaintdevice.html#protected-functions">QPaintDevice</a></li>
<li><div class="fn"/>1 protected slot inherited from <a href="qwidget.html#protected-slots">QWidget</a></li>
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<a name="details"></a>
<hr />
<h2>Detailed Description</h2>
<p>The QRubberBand class provides a rectangle or line that can indicate a selection or a boundary.</p>
<p>A rubber band is often used to show a new bounding area (as in a <a href="qsplitter.html">QSplitter</a> or a <a href="qdockwidget.html">QDockWidget</a> that is undocking). Historically this has been implemented using a <a href="qpainter.html">QPainter</a> and XOR, but this approach doesn't always work properly since rendering can happen in the window below the rubber band, but before the rubber band has been "erased".</p>
<p>You can create a QRubberBand whenever you need to render a rubber band around a given area (or to represent a single line), then call <a href="qrubberband.html#setGeometry">setGeometry</a>(), <a href="qrubberband.html#move">move</a>() or <a href="qrubberband.html#resize">resize</a>() to position and size it. A common pattern is to do this in conjunction with mouse events. For example:</p>
<pre> void Widget::mousePressEvent(QMouseEvent *event)
{
origin = event->pos();
if (!rubberBand)
rubberBand = new QRubberBand(QRubberBand::Rectangle, this);
rubberBand->setGeometry(QRect(origin, QSize()));
rubberBand->show();
}
void Widget::mouseMoveEvent(QMouseEvent *event)
{
rubberBand->setGeometry(QRect(origin, event->pos()).normalized());
}
void Widget::mouseReleaseEvent(QMouseEvent *event)
{
rubberBand->hide();
<span class="comment">// determine selection, for example using QRect::intersects()</span>
<span class="comment">// and QRect::contains().</span>
}</pre>
<p>If you pass a parent to QRubberBand's constructor, the rubber band will display only inside its parent, but stays on top of other child widgets. If no parent is passed, QRubberBand will act as a top-level widget.</p>
<p>Call <a href="qwidget.html#show">show</a>() to make the rubber band visible; also when the rubber band is not a top-level. Hiding or destroying the widget will make the rubber band disappear. The rubber band can be a <a href="qrubberband.html#Shape-enum">Rectangle</a> or a <a href="qrubberband.html#Shape-enum">Line</a> (vertical or horizontal), depending on the <a href="qrubberband.html#shape">shape</a>() it was given when constructed.</p>
<hr />
<h2>Member Type Documentation</h2>
<h3 class="fn"><a name="Shape-enum"></a>enum QRubberBand::Shape</h3>
<p>This enum specifies what shape a <a href="qrubberband.html">QRubberBand</a> should have. This is a drawing hint that is passed down to the style system, and can be interpreted by each <a href="qstyle.html">QStyle</a>.</p>
<p><table border="1" cellpadding="2" cellspacing="1" width="100%">
<tr><th width="25%">Constant</th><th width="15%">Value</th><th width="60%">Description</th></tr>
<tr><td valign="top"><tt>QRubberBand::Line</tt></td><td align="center" valign="top"><tt>0</tt></td><td valign="top">A <a href="qrubberband.html">QRubberBand</a> can represent a vertical or horizontal line. Geometry is still given in <a href="qwidget.html#rect-prop">rect</a>() and the line will fill the given geometry on most styles.</td></tr>
<tr><td valign="top"><tt>QRubberBand::Rectangle</tt></td><td align="center" valign="top"><tt>1</tt></td><td valign="top">A <a href="qrubberband.html">QRubberBand</a> can represent a rectangle. Some styles will interpret this as a filled (often semi-transparent) rectangle, or a rectangular outline.</td></tr>
</table></p>
<hr />
<h2>Member Function Documentation</h2>
<h3 class="fn"><a name="QRubberBand"></a>QRubberBand::QRubberBand ( <a href="qrubberband.html#Shape-enum">Shape</a> <i>s</i>, <a href="qwidget.html">QWidget</a> * <i>p</i> = 0 )</h3>
<p>Constructs a rubber band of shape <i>s</i>, with parent <i>p</i>.</p>
<p>By default a rectangular rubber band (<i>s</i> is <tt>Rectangle</tt>) will use a mask, so that a small border of the rectangle is all that is visible. Some styles (e.g., native Mac OS X) will change this and call <a href="qwidget.html#windowOpacity-prop">QWidget::setWindowOpacity</a>() to make a semi-transparent filled selection rectangle.</p>
<h3 class="fn"><a name="dtor.QRubberBand"></a>QRubberBand::~QRubberBand ()</h3>
<p>Destructor.</p>
<h3 class="fn"><a name="move"></a>void QRubberBand::move ( int <i>x</i>, int <i>y</i> )</h3>
<p>Moves the rubberband to point (<i>x</i>, <i>y</i>).</p>
<p>See also <a href="qrubberband.html#resize">resize</a>().</p>
<h3 class="fn"><a name="move-2"></a>void QRubberBand::move ( const <a href="qpoint.html">QPoint</a> & <i>p</i> )</h3>
<p>This is an overloaded member function, provided for convenience.</p>
<p>Moves the rubberband to point <i>p</i>.</p>
<p>See also <a href="qrubberband.html#resize">resize</a>().</p>
<h3 class="fn"><a name="resize"></a>void QRubberBand::resize ( int <i>width</i>, int <i>height</i> )</h3>
<p>Resizes the rubberband so that its width is <i>width</i>, and its height is <i>height</i>.</p>
<p>See also <a href="qrubberband.html#move">move</a>().</p>
<h3 class="fn"><a name="resize-2"></a>void QRubberBand::resize ( const <a href="qsize.html">QSize</a> & <i>size</i> )</h3>
<p>This is an overloaded member function, provided for convenience.</p>
<p>Resizes the rubberband so that its new size is <i>size</i>.</p>
<p>See also <a href="qrubberband.html#move">move</a>().</p>
<h3 class="fn"><a name="setGeometry"></a>void QRubberBand::setGeometry ( const <a href="qrect.html">QRect</a> & <i>rect</i> )</h3>
<p>Sets the geometry of the rubber band to <i>rect</i>, specified in the coordinate system of its parent widget.</p>
<p>See also <a href="qwidget.html#geometry-prop">QWidget::geometry</a>.</p>
<h3 class="fn"><a name="setGeometry-2"></a>void QRubberBand::setGeometry ( int <i>x</i>, int <i>y</i>, int <i>width</i>, int <i>height</i> )</h3>
<p>This is an overloaded member function, provided for convenience.</p>
<p>Sets the geometry of the rubberband to the rectangle whose top-left corner lies at the point (<i>x</i>, <i>y</i>), and with dimensions specified by <i>width</i> and <i>height</i>. The geometry is specified in the parent widget's coordinate system.</p>
<h3 class="fn"><a name="shape"></a><a href="qrubberband.html#Shape-enum">Shape</a> QRubberBand::shape () const</h3>
<p>Returns the shape of this rubber band. The shape can only be set upon construction.</p>
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