llucax / pausable_timer

A Dart timer that can be paused, resumed and reset.

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pausable_timer's Issues

dartfmt may be unnecessary

pausable_timer/.github/workflows/ci.yml

Line 32 in 40cf0d2

run: dartfmt --set-exit-if-changed --dry-run --fix lib test example

Running the dartfmt command in the CI may be unnecessary since

pausable_timer/.github/workflows/ci.yml

Line 27 in 40cf0d2

uses: zgosalvez/github-actions-analyze-flutter@v1

already runs it. See https://github.com/zgosalvez/github-actions-analyze-dart/blob/17a5ca792b39421bdaace447ba65be49af8d907d/src/index.js#L96.

Add a periodic timer flavor

There has been already a couple of requests for an easy way to create a pausable periodic timer in #19.

People seems to expect a PausableTimer.periodic() constructor, even when it's trivial to build on top of PausableTimer bacause it trivial to reset it and start it again.

Example:

timer = PausableTimer(
    Duration(seconds: 1),
    () {
      // This is really what your callback do.
      print('A period has passed');

      // we know the callback won't be called before the constructor ends, so
      // it is safe to use !
      timer
        ..reset()
        ..start();
    },
  )..start();

Once you want your timer to go away, you can just .pause() it and that's it. There is the caveat that if the actual work your callback does takes too long, the period will stretch. If you reset the timer before doing the actual work, it can be called without any further wait if it took longer than the period. Finally the time it takes for the work to be done can be calculated and the duration of the timer adjusted accordingly, which gets much less trivial, so maybe it is a worthy addition anyway 🤔

Automate publishing

It seems it's possible to automate publishing through GitHub Actions.

It would be nice to have this implemented.

A reference to the `PausableTimer` should be passed into `callback` to eliminate the requirement for storing an instance externally.

Use `dart:core` `Stopwatch` instead of depending on `clock`

Stopwatch exists in dart:core, so we should use it in this package instead of depending unnecessarily on clock.

Trying to make a countdown timer for video recording, but the callback is fired only once.

I tried the same with the inbuilt Timer.Periodic(), but pausing and resuming was so erratic; I had a time limit of 10 seconds, but pausing and resuming multiple times causes the total recording time to go over that limit.
I stumbled across this library from an SO answer.

When I replaced Timer.Periodic with PausableTimer, I see that it is fired only once.

Here is the sample code:

 int _start= 10;

 void startTimer() {    
    _timer = PausableTimer(
      Duration(seconds: 1),
      () {
        if (_start <= 0) {         
          recordVideo();
          setState(() {
            _isRecording = true;
          });
        } else {
          setState(() {
            _start = _start - 1;            
          });          
        }
      },
    )..start();
  }

This method will be called when the recording button is pressed.
recordVideo() is what I call to either start recording (along with startTime()) or end recording.

I know you're busy and haven't touched Dart in years, but can you help me understand what is that I'm doing wrong here and why is it being called only once?

Pause timer periodic?

EDIT: See #45 for an example on how to implement this.

Declaring and using the timer in init state does not work like timer.periodic.

What is meaning by "pause"?

I try to have a simple timer and need to pause it:

late final PausableTimer timer;

timer = PausableTimer(Duration(seconds: 1), () {
    print('Fired!');
    timer
        ..reset()
       ..start();
    });
    timer.start();

now I want to pause it:

timer!.pause();

But after starting again with timer!.start(); it starts from millisecond 0.
This is not good because I never hit exactly at millisecond 0 when pausing, but maybe at 323 millisecond or similar.

How can I restart the timer from the exact position where i paused it?