System back goes to history on profile

[micahmo]

Pull Request Description

This PR taps into the system back button to navigate from "Saved" to "History" on the profile page. This is an Android-specific thing, but I definitely agree that it makes sense for Back to undo the most recent navigation action, even within a page.

Issue Being Fixed

Issue Number: N/A

Screenshots / Recordings

qemu-system-x86_64_20EtAWrqyj.mp4

Checklist

• Did you update CHANGELOG.md?
• Did you use localized strings where applicable?
• Did you add semanticLabels where applicable for accessibility?

[hjiangsu]

If this is an Android-specific thing, then I would wrap the setState logic with the Android platform!

e.g.,

if (Platform.isAndroid) {
  setState(() => { ... });
}

[micahmo]

If this is an Android-specific thing, then I would wrap the setState logic with the Android platform!

Well, maybe I shouldn't say it's Android-specific. Any OS that has a back button as recognized by the BackButtonInterceptor package should use this functionality. 😊 Realistically it's probably just Android, but it's nice to let the package handle that detection for us. I think the less custom code the better. Also note that we use BackButtonInterceptor several other places already and don't have explicit OS checks.

thunder/lib/community/pages/community_page.dart

Line 70 in 4d91b89

BackButtonInterceptor.add(_handleBack);

thunder/lib/community/pages/community_page.dart

Lines 494 to 499 in 4d91b89

	FutureOr<bool> _handleBack(bool stopDefaultButtonEvent, RouteInfo info) async {
	if (context.read<ThunderBloc>().state.isFabOpen) {
	context.read<ThunderBloc>().add(const OnFabToggle(false));
	}
	if (currentCommunityBloc != null) {

[hjiangsu]

Ahh okay, that makes a bit more sense!