createController method
Creates an additional AnimationController instance that gets initialized and disposed by this mixin.
Optionally you can limit the framerate (fps) by specifying a target fps
value.
You can create an unbound AnimationController by setting the unbounded
parameter.
Implementation
AnimationController createController({
bool unbounded = false,
int? fps,
}) {
final instance = _newAnimationController(unbounded: unbounded, fps: fps);
_controllerInstances.add(instance);
return instance;
}