title: How to check if flutter toast already on screen?
body: <p>I want to show a toast message on my app whenever right condition is met based on some integer values calculation. This condition is met often and I want to show a toast message onScreen. I chose <a href="https://pub.dev/packages/fluttertoast" rel="nofollow noreferrer">flutter toast</a> plugin for this. But sometimes the method is sending too many toast that toast message consists even after the app is closed. So I want to know if a toast message already on screen and cancel if so. </p>
  
  <p>How do I check if flutter toast already on screen?</p>
  
  <p>Alternatively please suggest me other dialogue showing way on flutter.</p>
  
  <pre><code>//check if exist then cancel. Or show.
  Fluttertoast.showToast(
          msg: "This is condition met Toast",
          toastLength: Toast.LENGTH_SHORT,
          gravity: ToastGravity.CENTER,
          timeInSecForIosWeb: 1,
          backgroundColor: Colors.red,
          textColor: Colors.white,
          fontSize: 16.0
      );
  </code></pre>