Question 75524 in Flutter Question posted in
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problems with restarting countdown – Flutter

i am trying to make it so that when the timer finishes, it automatically restarts but it seems i am running into some problems. here is the code

int _start = 7;
  int? selectedValue;


  void startTimer() {
    const oneSec = Duration(seconds: 1);
    _timer = Timer.periodic(
      oneSec,
          (Timer timer) {
        if (_start == 0) {
          setState(() {});
        } else {
          setState(() {
            _start--;
          });
        }
      },
    );
  }
  void restartTimer() {
    if (_timer != null) {
      _timer.cancel();
    }
   setState(() {
     _start = 5;
   });
    startTimer();
  }
  @override
  void initState() {
    // TODO: implement initState
    startTimer();
    restartTimer();

i would appreciate a fix to this problem

Tags:

3

Answers


  1. 0

    you need to call restartTimer() after the timer reaches zero

    if (_start == 0) {
    setState(() {});
    restartTimer();
}

    I would also suggest allowing zero and restarting after

    if (_start < 0) {
    restartTimer();
}
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  2. 0

    If you could send the whole snippet it may be easier to see what is wrong but from what I can already see, you put the restart timer method in the initState, which means, the method will be called only once and at the wrong time.

    What I would suggest is:

         int _start = 7;
      int? selectedValue;
    
    
      void startTimer() {
        const oneSec = Duration(seconds: 1);
        _timer = Timer.periodic(
          oneSec,
              (Timer timer) {
            if (_start == 0) {
              setState(() {
                restartTimer();
              });
            } else {
              setState(() {
                _start--;
              });
            }
          },
        );
      }
      void restartTimer() {
        if (_timer != null) {
          _timer.cancel();
        }
       setState(() {
     _start = 5;
   });
    startTimer();
  }
  @override
  void initState() {
    // TODO: implement initState
    startTimer();

    Here I took away the restart timer method and put it inside your start method where you check if the countdown is 0 or not.
    Don’t forget to not put the int _start = 7 into the build, else when you will set the state again, the "start" will be 7 instead of 5 as you intended in your method (and the _start– won’t work either).

    Hope it helped.

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  3. 0

    Change this way,

    void startTimer() {
      const oneSec = Duration(seconds: 1);
      _timer = Timer.periodic(
        oneSec,
        (Timer timer) {
          if (_start == 0) {
            setState(() {});
            restartTimer();
          } else {
            setState(() {
              _start--;
            });
          }
        },
      );
    }

    and

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