Look at this markup:
<asp:UpdatePanel ID="Panel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:DropDownList ID="cboBox1" ClientIDMode="Static" AutoPostBack="true" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:DropDownList ID="cboBox2" runat="server" />
<asp:UpdateProgress ID="UpdateProgress1" style="display: inline" AssociatedUpdatePanelID="Panel1" DynamicLayout="false" DisplayAfter="0" runat="server">
<ProgressTemplate>
<img src='<%= ResolveClientUrl("~/Images/indicator.gif")%>' border="0" alt="" />
</ProgressTemplate>
</asp:UpdateProgress>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="cboBox1" EventName="SelectedIndexChanged" />
</Triggers>
</asp:UpdatePanel>
The UpdateProgress control worked initially, but broke when we added ClientMode="Static" to the cboBox1. Reverting it back to AutoID is not an option, so I need to find solutions that allow the UpdateProgress panel to work with ClientIDMode="Static".
Also, could someone add "clientidmode" to the list of tags?