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<title>Qt 4.8: QML Gradient Element</title>
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<a href="index.html" class="qtref"><span>Qt Reference Documentation</span></a>
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<li><a href="qdeclarativeelements.html">QML Elements</a></li>
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<h3><a name="toc">Contents</a></h3>
<ul>
<li class="level1"><a href="#properties">Properties</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
<li class="level2"><a href="#example-usage">Example Usage</a></li>
<li class="level2"><a href="#performance-and-limitations">Performance and Limitations</a></li>
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<h1 class="title">QML Gradient Element</h1>
<span class="subtitle"></span>
<!-- $$$Gradient-brief -->
<p>The Gradient item defines a gradient fill. <a href="#details">More...</a></p>
<!-- @@@Gradient -->
<p>This element was introduced in Qt 4.7.</p>
<ul>
<li><a href="qml-gradient-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="properties"></a>
<h2>Properties</h2>
<ul>
<li class="fn"><b><b><a href="qml-gradient.html#stops-prop">stops</a></b></b> : list<GradientStop></li>
</ul>
<!-- $$$Gradient-description -->
<a name="details"></a>
<h2>Detailed Description</h2>
<p>A gradient is defined by two or more colors, which will be blended seamlessly.</p>
<p>The colors are specified as a set of <a href="qml-gradientstop.html">GradientStop</a> child items, each of which defines a position on the gradient from 0.0 to 1.0 and a color. The position of each <a href="qml-gradientstop.html">GradientStop</a> is defined by setting its <a href="qml-gradientstop.html#position-prop">position</a> property; its color is defined using its <a href="qml-gradientstop.html#color-prop">color</a> property.</p>
<p>A gradient without any gradient stops is rendered as a solid white fill.</p>
<p>Note that this item is not a visual representation of a gradient. To display a gradient, use a visual element (like <a href="qml-rectangle.html">Rectangle</a>) which supports the use of gradients.</p>
<a name="example-usage"></a>
<h2>Example Usage</h2>
<div class="float-right"><p><img src="images/qml-gradient.png" alt="" /></p>
</div><p>The following example declares a <a href="qml-rectangle.html">Rectangle</a> item with a gradient starting with red, blending to yellow at one third of the height of the rectangle, and ending with green:</p>
<pre class="qml"> <span class="type"><a href="qml-rectangle.html">Rectangle</a></span> {
<span class="name">width</span>: <span class="number">100</span>; <span class="name">height</span>: <span class="number">100</span>
<span class="name">gradient</span>: <span class="name">Gradient</span> {
<span class="type"><a href="qml-gradientstop.html">GradientStop</a></span> { <span class="name">position</span>: <span class="number">0.0</span>; <span class="name">color</span>: <span class="string">"red"</span> }
<span class="type"><a href="qml-gradientstop.html">GradientStop</a></span> { <span class="name">position</span>: <span class="number">0.33</span>; <span class="name">color</span>: <span class="string">"yellow"</span> }
<span class="type"><a href="qml-gradientstop.html">GradientStop</a></span> { <span class="name">position</span>: <span class="number">1.0</span>; <span class="name">color</span>: <span class="string">"green"</span> }
}
}</pre>
<br style="clear: both" /><a name="performance-and-limitations"></a>
<h2>Performance and Limitations</h2>
<p>Calculating gradients can be computationally expensive compared to the use of solid color fills or images. Consider using gradients for static items in a user interface.</p>
<p>In Qt 4.7, only vertical, linear gradients can be applied to items. If you need to apply different orientations of gradients, a combination of rotation and clipping will need to be applied to the relevant items. This can introduce additional performance requirements for your application.</p>
<p>The use of animations involving gradient stops may not give the desired result. An alternative way to animate gradients is to use pre-generated images or SVG drawings containing gradients.</p>
<p><b>See also </b><a href="qml-gradientstop.html">GradientStop</a>.</p>
<!-- @@@Gradient -->
<h2>Property Documentation</h2>
<!-- $$$stops -->
<div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="stops-prop"></a><span class="qmlreadonly">read-only</span><span class="name">stops</span> : <span class="type"><a href="qml-list.html">list</a></span><<span class="type"><a href="qml-gradientstop.html">GradientStop</a></span>></p></td></tr></table></div><div class="qmldoc"><p>This property holds the gradient stops describing the gradient.</p>
<p>By default, this property contains an empty list.</p>
<p>To set the gradient stops, define them as children of the Gradient element.</p>
</div></div><!-- @@@stops -->
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