dispose method
Disposes the view.
The UiKitViewController object is unusable after calling this.
The id
of the platform view cannot be reused after the view is
disposed.
Implementation
Future<void> dispose() async {
_debugDisposed = true;
await SystemChannels.platform_views.invokeMethod<void>('dispose', id);
PlatformViewsService._instance._focusCallbacks.remove(id);
}