AnimationController.unbounded constructor

  1. {double value = 0.0,
  2. Duration? duration,
  3. Duration? reverseDuration,
  4. String? debugLabel,
  5. required TickerProvider vsync,
  6. AnimationBehavior animationBehavior = AnimationBehavior.preserve}

Creates an animation controller with no upper or lower bound for its value.

  • value is the initial value of the animation.

  • duration is the length of time this animation should last.

  • debugLabel is a string to help identify this animation during debugging (used by toString).

  • vsync is the required TickerProvider for the current context. It can be changed by calling resync. See TickerProvider for advice on obtaining a ticker provider.

This constructor is most useful for animations that will be driven using a physics simulation, especially when the physics simulation has no pre-determined bounds.


  double value = 0.0,
  required TickerProvider vsync,
  this.animationBehavior = AnimationBehavior.preserve,
}) : lowerBound = double.negativeInfinity,
     upperBound = double.infinity,
     _direction = _AnimationDirection.forward {
  if (kFlutterMemoryAllocationsEnabled) {
  _ticker = vsync.createTicker(_tick);