TextFormField validator text

I'm new to flutter. Is there any way to know if the validator text of a text form field is currently being shown on the screen? I would like to setState of a value if the validator is being shown. Thoughts?

You can declare a state and then update it's value.

    TextFormField(
        validator: (value) {
          if (value.isEmpty) {
            setState(() {
              _isValidatorVisible = true;
            });
            return 'Please enter a value';
          }
          setState(() {
            _isValidatorVisible = false;
          });
          return null;
        },
      ),

In this example, if the TextField is empty you display an indicator. Since you know you showing the indicator, you can use that information and set the state.