I am under the impression that using AutomaticKeepAliveClientMixin would prevent the states dispose() callback from being called when the Widget isn't visible anymore.
However, I have a situation where dispose() and initState() get called every time I hide/show a Widget, even though I implemented AutomaticKeepAliveClientMixin correctly.
class IdleScreenState extends State<IdleScreen> with AutomaticKeepAliveClientMixin {
@override
void initState() {
super.initState();
print('IdleScreen initState');
}
@override
void dispose() {
print('IdleScreen dispose');
super.dispose();
}
@override
Widget build(BuildContext context) {
super.build(context);
// ...build the page...
}
@override
bool get wantKeepAlive => true;
}
This is how I hide/show this Widget
class MainScreen extends State<MainScreen> with AutomaticKeepAliveClientMixin {
@override
Widget build(BuildContext context) {
super.build(context);
return somecondition ? IdleScreen() : OtherScreen();
}
@override
bool get wantKeepAlive => true;
}
Every time this Widget (screen) is shown, initState()gets called, and every time I hide it, dispose() gets called. It's as if the AutomaticKeepAliveClientMixin has no effect. All other similar issues I could find seem to be due to either missing the wantKeepAlive => true or the super.build(context), but they are 100% there in the code.
I tried supplying a GlobalKey for IdleScreen as well, but that didn't have any effect.
However, if I use an IndexedStack or Offstage to hide/show the widget, it works as expected (initState() and dispose() don't get called when hiding/showing the widget).
IndexedStack(
index: somecondition ? 0 : 1,
children: [
IdleScreen(),
OtherScreen()
],
),
Maybe I'm mistaken, but isn't the whole purpose of AutomaticKeepAliveClientMixin to not have to manually keep the widget around using this technique?
This is in a web project, if that matters.
