exit pop up flutter

 @override
  Widget build(BuildContext context) {
    return PopScope(
        canPop: false,
        onPopInvokedWithResult: (didPop, result) {
          if (didPop) {
            return;
          }
          showExitPopup(context);
        },
        child: Scaffold(
        )
  }


 Future<bool> showExitPopup(context) async {
    return await showDialog(
        context: context,
        builder: (BuildContext context) {
          return AlertDialog(
            content: SizedBox(
              height: 90,
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Text("Do you want to exit?"),
                  SizedBox(height: 20),
                  Row(
                    children: [
                      Expanded(
                        child: ElevatedButton(
                          onPressed: () {
                            if (kDebugMode) {
                              print('yes selected');
                            }
                            exit(0);
                          },
                          style: ElevatedButton.styleFrom(
                              backgroundColor: ProjectColors.appbarColor),
                          child: Text(
                            "Yes",
                            style: TextStyle(color: ProjectColors.white),
                          ),
                        ),
                      ),
                      SizedBox(width: 15),
                      Expanded(
                          child: ElevatedButton(
                            onPressed: () {
                              Navigator.of(context).pop();
                            },
                            style: ElevatedButton.styleFrom(
                              backgroundColor: Colors.white,
                            ),
                            child:
                            Text("No", style: TextStyle(color: Colors.black)),
                          ))
                    ],
                  )
                ],
              ),
            ),
          );
        });
  }