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avoid-empty-setstate

added in: 1.3.0
warning
Pro+
preset: recommended

Warns when a setState callback is empty.

Calling setState with an empty callback will still cause the widget to be re-rendered, but since it does not change the state, an empty callback is usually a sign of a bug.

Example​

❌ Bad:

class _FooState extends State<StatefulWidget> {
  Widget build(context) {
    return FooWidget(
      onChange: (value) async {
        // LINT: Avoid calling 'setState' with an empty callback. Try updating the callback or removing this invocation.
        setState(() {});
      },
    );
  }
}

✅ Good:

class _FooState extends State<StatefulWidget> {
  String _myState;

  Widget build(context) {
    return FooWidget(
      onChange: (value) async {
        setState(() {
          _myState = 'changed';
        });
      },
    );
  }
}

Additional Resources​