Set value or SelectedIndex functionality not working In AspxComboBox
<p>In my master page ,I have a <code>AspxComboBox</code> in side <code>ASPxMenu</code> item's <code>Template</code> tag I am able to access it on any <code>aspx</code> page but when I am trying set its Value Or SelectedIndex then changes not updating</p>

<pre><code>&lt;dx:MenuItem&gt;
          &lt;Template&gt;
             &lt;dx:ASPxComboBox ID="CbalarmSelect" runat="server" AutoPostBack="true" ViewStateMode="Enabled"  OnSelectedIndexChanged="cbalarmselect_changed"&gt;
           &lt;Items&gt;
              &lt;dx:ListEditItem Text="Select Option" Selected="true" Value="0" /&gt;
              &lt;dx:ListEditItem  Text="Sample" Value="1" /&gt;
              &lt;dx:ListEditItem Text="Demo" Value="2" /&gt;
           &lt;/Items&gt;
   &lt;/dx:ASPxComboBox&gt;
  &lt;/Template&gt;
 &lt;/dx:MenuItem&gt;
</code></pre>

<blockquote>
  <p>C# code to access this ComboBox</p>
</blockquote>

<pre><code> ASPxMenu item = (ASPxMenu)Master.FindControl("ASPxMenu1");  
 ASPxComboBox combo = (ASPxComboBox)item.Items.FindByName("AlarmSubscription").FindControl("CbalarmSelect");
 combo.SelectedIndex =1  ;
</code></pre>

<p>for test purpose I set its visibility false <code>combo.Visible = false;</code> but it is visible mean set functionality not working</p>