forward method
Starts running this animation forwards (towards the end).
Returns a TickerFuture that completes when the animation is complete.
If from
is non-null, it will be set as the current value before running
the animation.
The most recently returned TickerFuture, if any, is marked as having been canceled, meaning the future never completes and its TickerFuture.orCancel derivative future completes with a TickerCanceled error.
During the animation, status is reported as AnimationStatus.forward, which switches to AnimationStatus.completed when upperBound is reached at the end of the animation.
Implementation
@override
TickerFuture forward({double? from}) {
assert(_videoItem != null,
'SVGAAnimationController.forward() called after dispose()?');
return super.forward(from: from);
}