form

_buildSaveButton() {
    return RoundedLoadingButton(
      child: Text('Save', style: TextStyle(color: Colors.white)),
      controller: _btnController,
      onPressed: () {
        // save item
        if (_formKey.currentState!.validate()) {          
          // If the form is valid, display a snackbar. In the real world,
          // you'd often call a server or save the information in a database.
          ScaffoldMessenger.of(context)
              .showSnackBar(SnackBar(content: Text('Processing Data')));
        }
      },
    );
  }