title: Constantly Update UI in Java FX worker thread
body: <p>I have <code>Label label</code> in my FXML Application.</p>
  
  <p>I want this label to change once a second. Currently I use this:</p>
  
  <pre><code>        Task task = new Task&lt;Void&gt;() {
          @Override
          public Void call() throws Exception {
              int i = 0;
              while (true) {
                  lbl_tokenValid.setText(""+i);
                  i++;
                  Thread.sleep(1000);
              }
          }
      };
      Thread th = new Thread(task);
      th.setDaemon(true);
      th.start();
  </code></pre>
  
  <p>However nothing is happening.</p>
  
  <p>I don't get any errors or exceptions.
  I don't need the value I change the label to in my main GUI thread so I don't see the point in the <code>updateMessage</code> or <code>updateProgress</code> methods.</p>
  
  <p>What is wrong?</p>