Why does WillPopScope always disable swipe backwards?-CodePudding

When pushing on a new screen and wanting to disable the ability to swipe backwards I found the WillPopScope widget.

WillPopScope(
      onWillPop: () async => false,
      child: <some child>

however, it prevents the swipe gesture regardless of whether or not I return true of false. Is it possible to tell this widget that it can pop back on certain screen states?

So effectively I would have:

WillPopScope(
      onWillPop: () async => widget._canSwipeBack,
      child: <some child>

Right now I have add/not-add the widget based on the screen state which seems quite odd.

CodePudding user response：

Please refer to the below code

Without wrapping the widget with WillPopScope usually its performs Navigator.pop(context);

// disables swiping back
WillPopScope(
// disables swiping back or navigating back
 onWillPop: () {},
child: Scaffold(
body: Container(),
  ),
);

WillPopScope(
  onWillPop: () {
   // whenever you want to navigate back to specific route
    Navigator.push(
    context,
    MaterialPageRoute(builder: (context) => SecondRoute()),
    );
 },
 child: Scaffold(
   body: Container(),
  ),
);

WillPopScope(
  onWillPop: () {
// pop back
      Navigator.pop(context);
        },
child: Scaffold(
body: Container(),
  ),
);