Vibration doesn't respecting the pattern

[Alfatist]

Hello guys! I have the following code. In summary, The Vibration.vibrate pattern receives [4900, 100, 4900, 100, 4900, 100, 4900, 100] and intensity, a custom interpolation (it doesn't matter to the issue).

void vibrate() {
    late List<int> patternWaitVibrateMs;
    Duration selectedDuration = const Duration(seconds: 20);

    
    patternWaitVibrateMs = _createListWith4900and100Value(selectedDuration);

    List<int> intensitiesList =
      _generateGradientList(patternWaitVibrateMs.length);

    print(patternWaitVibrateMs); // [4900, 100, 4900, 100, 4900, 100, 4900, 100]
    Vibration.vibrate(
       pattern: patternWaitVibrateMs, intensities: intensitiesList);
  }

List<int> _createListWith100and4900Value(Duration timesToRepeat) {
  List<int> result = [];
  int resultWanted = timesToRepeat.inMilliseconds;
  int sum = 0;
  for (var i = 1; i <= timesToRepeat.inMilliseconds; i++) {
    if (i % 2 == 0) {
      result.add(100);
      sum += 100;
    } else {
      result.add(4900);
      sum += 4900;
    }
    if (sum >= resultWanted) break;
  }
  return result;
}

List<int> _generateGradientList(int lengthPatternWaitVibrate) {
  if (lengthPatternWaitVibrate < 2) {
    throw CustomError("List length must be at least 2");
  }
  List<int> listReturn = List.generate(lengthPatternWaitVibrate, (index) {
    double fraction =
        index / (lengthPatternWaitVibrate - 1); // Fração entre 0 e 1
    return (255 - fraction * (255 - 1)).round(); // Interpolation linear
  });
  return listReturn;
}

It's expected to wait 4900ms and then vibrate 100ms. It keeps vibrating at an unknown pattern, but notable not waiting 4900ms

Platform: Android 13; Samsung S20 FE
print(await Vibration.hasCustomVibrationsSupport()); returns true inside an async func.

[benjamindean]

Hey! What does it do instead? And which platform are you on?

[Alfatist]

Hey! What does it do instead? And which platform are you on?

Hi! I'm using Android 13, directly in a Samsung S20

Instead of follow the pattern, it keeps vibrating. I dunno the pattern, but it's not waiting 4900ms. I reversed the values ( [100, 4900, 100, 4900...]) but keeps not waiting.

Finally, running print(await Vibration.hasCustomVibrationsSupport()); returns true.

I'll add everything in the original issue

[ch-alexander]

@Alfatist

I'm not sure if this will help you or not.

We have an A20 device (also running Android 13) that was failing to run vibrations consecutively (not a pattern).

We found the device does support different duration lengths, but when we played them one after the other, the duration was always shorter than it should have been.

We adjusted the lines in vibration/android/src/main/java/com/benjaminabel/vibration/Vibration.java to remove the AudioAttrributes from the vibration calls.

new AudioAttributes.Builder()
    .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
    .setUsage(AudioAttributes.USAGE_ALARM)
    .build()

Our A20 devices, and others, now behave the same for us. Adhering to the vibration durations we request in sequence. Removing the same lines may fix the patterns for you.