title: Threading: Setting checkbox's visibility
body: <p>In a C#.NET windows application (winforms) I set the visibility of the checkbox to false:</p>
  
  <pre><code>checkBoxLaunch.Visible = true;
  </code></pre>
  
  <p>I started a thread.</p>
  
  <pre><code>Thread th = new Thread(new ThreadStart(PerformAction));
  th.IsBackground = true;
  th.Start();
  </code></pre>
  
  <hr>
  
  <p>The thread performs some stuff and sets the visibility to true:</p>
  
  <pre><code>private void PerformAction()
  {
  /*
  .
  .// some actions.
  */
      checkBoxLaunch.Visible = true;
  
  }
  </code></pre>
  
  <p>After the thread finishes its task, the checkbox is not visible to me.</p>
  
  <p>What am I missing?</p>