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    <h5>TouchPainter class</h5>
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    <h1>shouldRepaint method</h1>

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        <ol class="annotation-list">
          <li>@override</li>
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      <span class="returntype">bool</span>
      <span class="name ">shouldRepaint</span>
(<wbr><span class="parameter" id="shouldRepaint-param-oldDelegate"><span>covariant</span> <span class="type-annotation">CustomPainter</span> <span class="parameter-name">oldDelegate</span></span>)
      
    </section>
    <section class="desc markdown">
      <p>Called whenever a new instance of the custom painter delegate class is
provided to the <code>RenderCustomPaint</code> object, or any time that a new
<code>CustomPaint</code> object is created with a new instance of the custom painter
delegate class (which amounts to the same thing, because the latter is
implemented in terms of the former).</p>
<p>If the new instance represents different information than the old
instance, then the method should return true, otherwise it should return
false.</p>
<p>If the method returns false, then the <a href="ui_home_TouchPainter/TouchPainter/paint.html">paint</a> call might be optimized
away.</p>
<p>It's possible that the <a href="ui_home_TouchPainter/TouchPainter/paint.html">paint</a> method will get called even if
<a href="ui_home_TouchPainter/TouchPainter/shouldRepaint.html">shouldRepaint</a> returns false (e.g. if an ancestor or descendant needed to
be repainted). It's also possible that the <a href="ui_home_TouchPainter/TouchPainter/paint.html">paint</a> method will get called
without <a href="ui_home_TouchPainter/TouchPainter/shouldRepaint.html">shouldRepaint</a> being called at all (e.g. if the box changes
size).</p>
<p>If a custom delegate has a particularly expensive paint function such that
repaints should be avoided as much as possible, a <code>RepaintBoundary</code> or
<code>RenderRepaintBoundary</code> (or other render object with
<code>RenderObject.isRepaintBoundary</code> set to true) might be helpful.</p>
<p>The <code>oldDelegate</code> argument will never be null.</p>
    </section>
    
    <section class="summary source-code" id="source">
      <h2><span>Implementation</span> </h2>
      <pre class="language-dart"><code class="language-dart">@override
bool shouldRepaint(CustomPainter oldDelegate) {
  return true;
}</code></pre>
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