Answers for "flutter remove previous route"

flutter clear navigation stack

Navigator.pushAndRemoveUntil(
      context,
      MaterialPageRoute(
        builder: (BuildContext context) => LoginPage(),
      ),
      (route) => false,
    );

push and remove until flutter

//named
Navigator.of(context)
    .pushNamedAndRemoveUntil('/login', (Route<dynamic> route) => false);
    
//not named
Navigator.of(context).pushAndRemoveUntil(MaterialPageRoute(builder: (context) =>
    LoginScreen()), (Route<dynamic> route) => false),