Flutter “不要跨异步间隙使用 BuildContexts”

Question

Basically I want to return to my LoginView when the user presses Logout in the dialog.

onSelected: (value) async {
              switch (value) {
                case MenuAction.logout:
                  final shouldLogout = await showLogOutDialog(context);
                  final navigator = Navigator.of(context);
                  if (shouldLogout) {
                    await FirebaseAuth.instance.signOut();
                    navigator.pushNamedAndRemoveUntil(
                      '/login',
                      (route) => false,
                    );
                  }
              }
            },

showLogoutDialog function:

Future<bool> showLogOutDialog(BuildContext context) {
  return showDialog<bool>(
    context: context,
    builder: (context) {
      return AlertDialog(
        title: const Text('Sign out'),
        content: const Text('Are you sure you want to sign out?'),
        actions: [
          TextButton(
            onPressed: () {
              Navigator.of(context).pop(false);
            },
            child: const Text('Cancel'),
          ),
          TextButton(
            onPressed: () {
              Navigator.of(context).pop(true);
            },
            child: const Text('Logout'),
          ),
        ],
      );
    },
  ).then((value) => value ?? false);

I get this error: "Do not use BuildContexts across async gaps.".

Anyone who can help me?

Thanks in advance!

Answer 1

It is unsafe, try checking if the widget is mounted or not.

if (mounted) {
  Navigator.of(context);
}

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