Issue with getting control id when tabcontainer is used

Question

I have an AJAX Control Toolkit TabContainer in my ASP.NET page. In one of the tabs in the TabContainer, there is a GridView. Now, I have an UpdatePanel for which I want to give trigger as "RowCommand" of GridView mentioned above. The UpdatePanel is outside the TabContainer. But when I give the GridView id, I am getting the error:

A control with ID 'grvSummary' could not be found for the trigger in UpdatePanel 'updSegment'.

Trigger markup:

<asp:AsyncPostBackTrigger ControlID="grvSummary" EventName="RowCommand" />

Answer 1

You will have to programmatically add the trigger to your UpdatePanel. This is because your GridView may or may not start in a different ContentPlaceHolder than the UpdatePanel (namely, the <ContentTemplate> of your TabContainer). Like this (note that this really needs to be done in Page_Init, due to the Page Life Cycle):

protected void Page_Init(object sender, EventArgs e)
{
    AsyncPostBackTrigger trig = new AsyncPostBackTrigger();
    trig.ControlID = grvSummary.UniqueID;
    trig.EventName = "RowCommand";
    updSegment.Triggers.Add(trig);
}

It looks like this may be a problem with ASP.NET / AJAX assuming the wrong Control.UniqueID value for the Control being used as a trigger.

Source: Triggering an UpdatePanel in a different ContentPlaceHolder