  </dt>
        <dd>
          An opaque handle to a backdrop filter engine layer. <a href="dart-ui/BackdropFilterEngineLayer-class.html">[...]</a>
        </dd>
        <dt id="CallbackHandle">
          <span class="name "><a href="dart-ui/CallbackHandle-class.html">CallbackHandle</a></span>         
        </dt>
        <dd>
          A wrapper for a raw callback handle. <a href="dart-ui/CallbackHandle-class.html">[...]</a>
        </dd>
        <dt id="Canvas">
          <span class="name "><a href="da