I'm working to do a simple countdown and it works great

but the problem is that when I switch to another page, the countdown counter does not continue from where it left off.

eg I initialize the counter: 10 , 9, 8 ...

the page changes and the counter starts again at 10

here is my code

My package: import 'package:circular_countdown_timer/circular_countdown_timer.dart';

class _CircularTimerState extends State<CircularTimer> {
  final CountDownController controller = CountDownController();

  @override
  void initState() {
    super.initState();
    
  }

  void miningCounter() {
    controller.start();
    final user = context.read<FirebaseAuthMethods>().user;

    dbRef.child(user.uid).child('miningEndTime').set(endTime);
  }



  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Circular Timer'),
        backgroundColor: primaryMaterialColor,
      ),
      body: Column(
        crossAxisAlignment: CrossAxisAlignment.center,
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          // Countdown Start Button
          CustomMiningButton(
            icon: Icons.start,
            onTap: miningCounter,
          ),

          CircularCountDownTimer(
            duration: 10,
            initialDuration: 0,
            controller: controller,
            width: MediaQuery.of(context).size.width * 0.2,
            height: MediaQuery.of(context).size.height * 0.2,
            autoStart: false,
          ),
        ],
      ),
    );
  }
}

CodePudding user response：

You need to remember what was the last number. You can use the SharedPreferences package:

Create a class:

class SharedPref {
  static late final SharedPreferences prefs;

  static initialize() async {
    prefs = await SharedPreferences.getInstance();
  }

  SharedPref._();
}

Call the initialize method in your main function:

void main() async {
   await SharedPref.initialize();
   runApp(...);
}

Then before you open the next page you save the value:

SharedPref.prefs.setInt("remaining", _remaining);

Have a variable that holds this number:

 final CountDownController controller = CountDownController();
 late int _remaining;
 bool _loading = true;

  @override
  void initState() {
    super.initState();
    
    _setRemaining();
  }

  _setRemaining() async {
    _remaining = await SharedPref.prefs.getInt("remaining");

    setState(() { _loading = false; });
  }


...

body: _loading ? CircularProgressIndicator() : Column(
        crossAxisAlignment: CrossAxisAlignment.center,
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          // Countdown Start Button
          CustomMiningButton(
            icon: Icons.start,
            onTap: miningCounter,
          ),

          CircularCountDownTimer(
            duration: 10,
            initialDuration: _remaining,
            controller: controller,
            width: MediaQuery.of(context).size.width * 0.2,
            height: MediaQuery.of(context).size.height * 0.2,
            autoStart: false,
          ),
        ],
      ),

CodePudding user response：

I think passing key to the page would work

Here is YouTube vedio for your case :-https://www.youtube.com/watch?v=sMD4Qxn9q_E