Flag to make sheet to not overflow its lower and upper bounds (strictier controller values range)

[Aqluse]

I faced a need to keep sheet strictly in its bounds, so, when I didn't find any out-of-box solution, I decided to play with it by myself. And what I got:

In _onVerticalDragUpdate function from RubberBottomSheet I replaced one line like this

//_controller.value -= details.primaryDelta / screenHeight * friction;

var newValue = controller.value - (details.primaryDelta / _screenHeight * friction);
        if (_someFlagThatMakesControllerBeAwareAboutSheetBounds) {
          if (newValue > controller.upperBound)
            newValue = controller.upperBound;
          else if (newValue < controller.lowerBound)
            newValue = controller.lowerBound;
        }
        controller.value = newValue;

And after some gestures that caused fling of RubberAnimationController to be called, sheet comes collapsed or even disappears. But I played with it too and added these lines before simulation object creates (because it caused division by zero inside) [Not sure if it's necessary after update edits, couldn't catch it again]

if (value == to)
      return null;

Upd: Also, controller should have added (_tick), right before notifyListeners():

// Strict boundaries enforced
    if(_someFlagThatMakesControllerBeAwareAboutSheetBounds && _value > upperBound)
      _value = upperBound;

So I hope it will appear in Rubber in a future.

[dickermoshe]

+1