fadeTo method

Future<void> fadeTo(double targetVolume, { Duration duration = const Duration(seconds: 2), Curve curve = Curves.linear, })

Fade To Target Volume

Tween volume from current level to targetVolume over duration following curve. Uses a ~60 FPS stepping loop for smoothness.

Edge Cases:

• If duration is very small, we still perform at least one step.

Implementation

Future<void> fadeTo(
    double targetVolume, {
      Duration duration = const Duration(seconds: 2),
      Curve curve = Curves.linear,
    }) async {
  final double start = _volume;
  final double end = targetVolume;
  const int fps = 60;
  int steps = (fps * duration.inMilliseconds / 1000).round();
  if (steps < 1) steps = 1; // ensure at least one step
  final frameDuration = Duration(milliseconds: (1000 / fps).round());

  FiftyAudioLogger.fade(start, end, duration, curve);

  for (int i = 0; i <= steps; i++) {
    final t = curve.transform(i / steps);
    final v = start + (end - start) * t;
    await _player.setVolume(v);
    _muted = v == 0.0;
    await Future.delayed(frameDuration);
  }
  _volume = targetVolume;
}