an class="parameter-name">parent</span>, </span> <span class="parameter" id="RegisterCallbackHandler-param-zone"><span class="type-annotation"><a href="dart-async/Zone-class.html">Zone</a></span> <span class="parameter-name">zone</span>, </span> <span class="parameter" id="RegisterCallbackHandler-param-f"><span class="type-annotation">R</span> <span class="parameter-name">f</span>()</span>)
    </section>

        <section class="summary source-code" id="source">
      <h2><span>Implementation</span></h2>
 