AnimationController stopped working because somehow vsync is not a named parameter anymore.

This line of code stopped working. 

```controller = AnimationController(duration: Duration(seconds: 3), vsync: this);```

It now shows an error saying:

    The named parameter &#39;vsync&#39; isn&#39;t defined.
    Try correcting the name to an existing named parameter&#39;s name, or defining a named parameter with the name &#39;vsync&#39;.dartundefined_named_parameter

I use this exact same code in two different apps, in one of them I just removed the fading text animation as a hot fix, but on the other app I need a real fix. Has anyone seen this problem recently? 

Note:

-This exact same code has been working for months and stopped working after an update. 

-The surrounding class does have: ```with TickerProviderStateMixin```

```
class FadingText extends StatefulWidget {
  final String text;
  final int seconds;
  final TextStyle style;

  FadingText({this.text, this.seconds, this.style});

  @override
  _FadingTextState createState() =&gt; _FadingTextState();
}

class _FadingTextState extends State&lt;FadingText&gt; with TickerProviderStateMixin {
  AnimationController controller;
  Animation animation;

  @override
  Widget build(BuildContext context) {
    return Container(
      child: FadeTransition(
        opacity: animation,
        child: Text(widget.text, style: widget.style,),
      ),
    );
  }

  @override
  void initState() {
    super.initState();

    controller = AnimationController(duration: Duration(seconds: widget.seconds), vsync: this);
    animation = Tween(begin: 0.5, end: 1.0).animate(controller);

    animation.addStatusListener((status) {
      if (status == AnimationStatus.completed) { controller.reverse(); }
      else if (status == AnimationStatus.dismissed) { controller.forward(); }
    });

    controller.forward();
  }


  @override
  void dispose() {
    controller.dispose();
    super.dispose();
  }

}
```


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        • Framework revision 7884420a0a (25 hours ago), 2020-07-31 20:20:00 +0200
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        • Dart version 2.10.0 (build 2.10.0-2.0.dev bd528bfbd6)
    
     
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    • No issues found!



All Animationcontroller Solutions on Gang of Coders

Total of 1 Animationcontroller Solutions

AnimationController The named parameter 'vsync' isn't defined