/code>'s <a href="flutter_page_video/AspectRatioVideoState/build.html">build</a> method depends on an object that can itself change
state, for example a <code>ChangeNotifier</code> or <code>Stream</code>, or some other object to
which one can subscribe to receive notifications, then the <code>State</code> should
subscribe to that object during <a href="flutter_page_video/AspectRatioVideoState/initState.html">initState</a>, unsubscribe from the old
object and subscribe to the new object when it changes in
<a