play method
Use this function to play this ImageSequenceAnimator.
Implementation
void play({double from: -1.0}) {
if (!_isReadyToPlay) return;
if (!_animationController!.isAnimating && widget.onStartPlaying != null) widget.onStartPlaying!(this);
if (from == -1.0)
_animationController!.forward();
else
_animationController!.forward(from: from);
}