How to set Preferred Orientation when Navigating back to home page

Question

How to fix screen orientation cannot back to normal when press the back button?

here soruce code: https://github.com/iyansr/traffic-manager-master

I've set Orientation inside and outside void initState() on both page, but when i go back to homepage, the screen orientation still lanscape.

I want the homepage always in potrait mode and the second page is always landscape

on home.dart:

...
  @override
  void initState() {
    super.initState();
    // Set portrait orientation
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.portraitDown,
      DeviceOrientation.portraitUp,
    ]);

    _dateTime = DateTime.parse(initDate);
  }
...

on counterpage.dart (landscape):

class _CounterPageState extends State<CounterPage> {
  @override
  void initState() {
    super.initState();
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.landscapeLeft,
      DeviceOrientation.landscapeRight,
    ]);
  }
...

Answer 1

initState() isn't called when you back, because your old page is still created, but not active. Maybe the simplest result here will be called setPrefferedOrintations() in dispose() method on second screen

class _CounterPageState extends State<CounterPage> {
  @override
  void initState() {
    super.initState();
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.landscapeLeft,
      DeviceOrientation.landscapeRight,
    ]);
  }

  @override
  void dispose() {
    // Set portrait orientation
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.portraitDown,
      DeviceOrientation.portraitUp,
    ]);
    super.dispose();
  }
}