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ASP C# UpdatePanel does not update contents

I am trying to update the datasource of a webdatagrid in an updatepanel. I am able to do this via a timer tick event
<asp:timer id="Timer1" runat="server" interval="10000" ontick="Timer1_Tick"></asp:timer>
<asp:updatepanel id="UpdatePanel1" runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick"/>
</Triggers>
<ContentTemplate>
<ig:WebDataGrid ID="WebDataGrid" runat="server" AutoGenerateColumns="false" >
</ig:WebDataGrid>
</ContentTemplate>
</asp:updatepanel>
And with the Tick event handler
protected void Timer1_Tick(object sender, EventArgs e)
{
WebDataGrid.DataSource = *a datatable*;
WebDataGrid.DataBind();
}
However, now when I try to do the same thing except instead of using the timer, use the WebDataGridMain_RowSelectionChanged event instead the webdatagrid does not update. I believe the new datasource value is still being sent to the client however the UpdatePanel does not seem to be updating the view.
<ig:WebDataGrid ID="WebDataGridMain" runat="server" AutoGenerateColumns="False" OnRowSelectionChanged="WebDataGridMain_RowSelectionChanged">
<ClientEvents AJAXResponse="AJAXResponseHandler" />
</ig:WebDataGrid>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="WebDataGridMain" EventName="RowSelectionChanged"/>
</Triggers>
<ContentTemplate>
<ig:WebDataGrid ID="WebDataGridDetail" runat="server" AutoGenerateColumns="false">
</ig:WebDataGrid>
</ContentTemplate>
</asp:UpdatePanel>
With the the similar event handler code below
protected void WebDataGridMain_RowSelectionChanged(object sender, Infragistics.Web.UI.GridControls.SelectedRowEventArgs e)
{
WebDataGridDetail.DataSource = *a datatable*;
WebDataGridDetail.DataBind();
}
There doesn't seem to be any difference between these two except for the type of event trigger. What should I change so that the UpdatePanel works with the RowSelectionChanged event?

Why is my first drop down getting refreshed in a cascaded setup?

I am trying to setup a cascaded drop down box where the first one will result in the second one's value being changes and so on. I have some markup like this:
<form id="ddlSelections" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server" EnablePartialRendering="true" />
<asp:UpdatePanel ID="UpdatePanel2" runat="server" ChildrenAsTriggers="true" UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="DDL1" EventName="SelectedIndexChanged" />
<asp:AsyncPostBackTrigger ControlID="DDL2" EventName="SelectedIndexChanged" />
</Triggers>
<ContentTemplate>
<asp:DropDownList ID="DDL1" OnSelectedIndexChanged="OnDDL1Change" AutoPostBack="true" runat="server" />
<asp:DropDownList ID="DDL2" OnSelectedIndexChanged="OnDDL2Change" AutoPostBack="true" runat="server" />
<asp:DropDownList ID="DDL3" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
</form>
And my code-behind is something like this:
protected void Page_Load(object sender, EventArgs e)
{
populateDDL1();
}
private void populateDDL1()
{
DDL1.Items.Clear();
// -- populate from SQL
}
protected void OnDDL1Change(object sender, EventArgs e)
{
DDL2.Items.Clear();
// -- populate from SQL
}
This is working except that everytime I click on the first drop down box, the values in the second drop down box get populated but the values in the first drop down box are being re-populated i.e. it looks like populateDDL1() is being called which of course will not be called unless Page_Load is called! I am failing to understand why this is the case. Any suggestions on where I am going wrong?

You are populating the first dropdownlist on every page load.
You need to do that only on the first load.
Wrap your populateDDL1 call in if (!IsPostBack), which is a backward way of saying to only populate it the first time the page loads.
To test this, put a breakpoint on that line in Page_Load.
Just because it's an ajax-y UpdatePanel doesn't mean that the server-side methods don't run.

Update ASP.NET panel asynchronously

I need some help with this problem:
Situation:
I've got a usercontrol (in SharePoint) that reads query string and processes it with an asynchronous event. While it's busy, a spinner is shown. After the event is finished, the updatepanel inside the usercontrol should update and show the message (+ hide the spinner)
Code: I've got a function that's called asynchronously on the UserControl_Unload event.
private delegate void AsyncFunction(string activation);
void UserControl_Unload(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
AsyncFunction dlgt = new AsyncFunction(this.CheckUrl);
AsyncCallback callback = new AsyncCallback(FunctionCallBack);
IAsyncResult ar = dlgt.BeginInvoke(activationcode, callback, null);
}
}
private void CheckUrl(string lalala)
{
// Some code
}
User control markup:
<asp:UpdatePanel runat="server" id="pnlContent" updatemode="Conditional" ChildrenAsTriggers="true">
<ContentTemplate>
<asp:UpdatePanel runat="server" id="pnlStatus" UpdateMode="Conditional" ChildrenAsTriggers="false">
<ContentTemplate>
<asp:Label runat="server" ID="lblMessage" />
<asp:LinkButton runat="server" ID="btnHome" Text="Terug naar welkom-pagina" PostBackUrl="<% $SPUrl:~sitecollection %>" />
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdatePanel runat="server" id="pnlGegevens" UpdateMode="Conditional" ChildrenAsTriggers="false">
<ContentTemplate>
<div><asp:Image runat="server" ID="imgLoading" AlternateText="Loading..." CssClass="gb_pl_loadingImage" ImageUrl="<% $SPUrl:~sitecollection/Style Library/GB-VW Styles/Images/ajax-loader.gif %>"/></div>
<div class="gb_pl_loading">Even geduld aub. De gebruiker wordt geactiveerd...</div>
</ContentTemplate>
</asp:UpdatePanel>
</ContentTemplate>
</asp:UpdatePanel>
This all works great, but when I need to update the panel, it doesn't work.
private void FunctionCallBack(IAsyncResult test)
{
pnlContent.Update()
}
Anyone who knows how to solve this? (if it's possible only use asp, c# or javascript)

Is it possible to fire off the asynchronous operation from the client? That is, display your page but include javascript that makes a webservice call? That way you at least have something to wait for, and your client will get notified becuase it initiated the request.
Otherwise I don't see how the page, which is already gone to the client, could be updated by the server once the async op finishes.

UpdatePanel not firing inside Wizard

I have an Update panel within a wizard:
<asp:WizardStep ID="WizardStep2" runat="server" StepType="Auto"
Title="Set the number of users required.">
...
<asp:UpdatePanel ID="UpdatePanel2" UpdateMode="Always" runat="server">
<ContentTemplate>
<asp:Label runat="server" ID="ProgressInd" Text="Progress..." />
<asp:Button runat="server" OnClick="GoButton_Click" ID="ProgressBtn" Text="Go" />
</ContentTemplate>
</asp:UpdatePanel>
</asp:WizardStep>
...
protected void GoButton_Click(object sender, EventArgs e)
{
ProgressInd.Text = "Progress... Moving";
}
When I take the update panel out of the wizard it works nicely but inside the wizard the click event just won't fire. I'm using Firefox to test, but IE doesn't work either. Any ideas or help appreciated.

For the record. Paolo spotted my problem. There were page validators that were preventing the event from firing.

asp.net timer to load page content

asp.net
c#
Our webpage currently contains a rather large web app which causes a lengthy delay when attemping to navigate to it. I'm currently implementing a WCF web service to utilize ajax but the delay is a concern to my employer so he wanted a quick and dirty fix in the mean time.
I would like to have the empty page load and then use a timer to load the content. This will cut down on perceived page load time but i'm unsure how to accomplish it.
Any help would be much appreciated
Shawn

Some code to get you started:
In the asp.net page:
<asp:Timer ID="Timer1" OnTick="Timer1_Tick" runat="server" Interval="1">
</asp:Timer>
<asp:UpdatePanel ID="updatePanel1" runat="server" UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" />
</Triggers>
<ContentTemplate>
.... your stuff here
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdateProgress ID="UpdateProgress1" runat="server" DisplayAfter="100">
<ProgressTemplate>
Please wait...
</ProgressTemplate>
</asp:UpdateProgress>
In the code behind:
protected void Timer1_Tick(object sender, EventArgs e)
{
this.Timer1.Enabled = false;
StartLongRunningTask();
}

Instead of a timer, you could flush the Response with Response.Flush().