requestPermission method

@override Future<PermissionStatus> requestPermission()

Implementation

@override
Future<PermissionStatus> requestPermission() async {
  switch (repository.status ?? PermissionStatus.granted) {
    case PermissionStatus.granted:
    case PermissionStatus.limited:
      // close permission page and back to the screen to request permission.
      break;
    case PermissionStatus.denied:
      // if the permission is mandatory to use app, keep permission page.
      await repository.request();
      if (repository.status == PermissionStatus.limited ||
          repository.status == PermissionStatus.granted) {
        update(state: PermissionViewState.grantedAndExit);
      }
      break;

    case PermissionStatus.permanentlyDenied:
      // goto settings
      bool ret = await openAppSettings();
      if (ret) {
        await repository.readPermissionStatus();
      }
      break;

    case PermissionStatus.restricted:
      // impossible to access
      break;
  }

  _handleStatus(repository.status);

  return repository.status ?? PermissionStatus.granted;
}