title: Android UI Components still running when React component is unmounted with react-router-native
body: <p>When moving my app's navigation handling from react-native-router-flux to react-router-native, I seem to have uncovered an issue in how my app's native UI omponents are handled.</p>
  
  <p>My app has several animated data plots that I've implemented in Java and imported into React Native as <a href="https://facebook.github.io/react-native/docs/native-components-android.html" rel="nofollow noreferrer">Native UI Components</a>. The visualizations are powered by some resource-hungry runnables on background threads that get started when the ui component is loaded. Previously, I stopped these threads by changing a prop of the native ui component (isVisible) to false.</p>
  
  <p>However, when navigating away from a screen containing one of these native ui components with react-router-native (which unmounts components upon transition), even though componentWillUnmount is called in the react component, the native threads powering my plots keep running. </p>
  
  <p>I tried to shut them down by changing the native ui component prop isVisible to false in componentWillUnmount, but even that doesn't fix the problem. Perhaps because there isn't another render of that component after componentWillUnmount?</p>
  
  <p>Does anyone have any ideas on how to force a native UI component and all of its processes to shut down when it's parent is unmounted?</p>