onWillPop: onWillPop is a callback method that returns a Future value; if true, the screen can be popped; if false, the screen will not be popped out . However, the screen can still be popped by calling the Navigator.
onWillPop: onWillPop is a callback method that returns a Future value; if true, the screen can be popped; if false, the screen will not be popped out . However, the screen can still be popped by calling the Navigator.