title: RadioButtonList set to AutoPostBack = true but still not firing OnSelectedIndexChanged
body: <p>I have 2 RadioButtonLists and I want only one option to be selected, f.i. if you select an option in List 1 the selection in List 2 should be cleared.</p>
  
  <p>AutoPostBack and EnableViewState is set to true, but still the Method never fires. I have also checked if the Index actually changes, it does. I think that the PostBack just doesn't occur, but I don'T know why.</p>
  
  <p>I'm thankful for any help.</p>
  
  <p>ascx:</p>
  
  <pre><code>&lt;asp:RadioButtonList ID="_listOne" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ListOneIndexChanged"&gt;
  &lt;/asp:RadioButtonList&gt;
  &lt;asp:RadioButtonList ID="_listTwo" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ListTwoIndexChanged"&gt;
  &lt;/asp:RadioButtonList&gt;
  </code></pre>
  
  <p>Code Behind:</p>
  
  <pre><code>protected void ListOneIndexChanged(object sender, EventArgs e)
  {
      _listTwo.ClearSelection();
  }
  protected void ListTwoIndexChanged(object sender, EventArgs e)
  {
      _listOne.ClearSelection();
  }
  </code></pre>