Tickers used by AnimationControllers should be disposed by calling dispose()

[kleyos]

Your widget doesn't have AnimationControllers.dispose() and always is falling down

_FlutterSwitchState#e50c7(ticker active) was disposed with an active Ticker.
I/flutter (20111): _FlutterSwitchState created a Ticker via its SingleTickerProviderStateMixin, but at the time
I/flutter (20111): dispose() was called on the mixin, that Ticker was still active. The Ticker must be disposed before
I/flutter (20111): calling super.dispose().
I/flutter (20111): Tickers used by AnimationControllers should be disposed by calling dispose() on the
I/flutter (20111): AnimationController itself. Otherwise, the ticker will leak.