didMount method
Implementation
@override
void didMount() {
assert(state._debugLifecycleState == _StateLifecycle.created);
// We check if state uses on of the mixins that support async initialization,
// which will delay the call to [_initState()] until resolved during the first build.
if (owner.isFirstBuild && state is PreloadStateMixin && !binding.isClient) {
_asyncInitState = (state as PreloadStateMixin).preloadState().then((_) => _initState());
} else {
_initState();
}
super.didMount();
}