title: How to set JavaFX-Alert into middle of actual monitor?
body: <p>I've got a static method in a class without knowing anything about the Application, Scene oder Stage. But I want to show an Alert in the middle of the actual used monitor.</p>
  
  <p>For example: My tool is on the right screen. I want to see the alert also there and not on the main screen.</p>
  
  <p>My method:</p>
  
  <pre><code>private static Alert createAlert(AlertType type, String title, String header, String content) {
      Alert alert = new Alert(type);
      alert.setTitle(title);
      if (!header.isEmpty()) {
          alert.setHeaderText(header);
      }
      alert.setContentText(content);
      alert.setResizable(true);
  
      alert.setX(0); // set this into the middle of used monitor
      alert.setY(0); // 
  
      return alert;
  }
  </code></pre>
  
  <p>How can I get the actual stage, scene or whatever to get its x- and y-position and use these information for setting x and y of the alert?</p>