Ajax ModalPopupExtender with update panal - asp.net

Question

I'm developing an Asp.net web site.
I'm using Ajax:ModalPopupExtender for displaying some information.
Html
<asp:UpdatePanel ID="upnlModelPopup" runat="server" UpdateMode="Conditional">
<ContentTemplate>
Form control goes here...............
<asp:Button ID="btnShow" runat="server" CssClass="btn" Text="Adjustment" OnClick="btnShow_Click" Enabled="true" />
<cc1:ModalPopupExtender ID="mpeAdjAmt" runat="server" TargetControlID="lblHead"
PopupControlID="pnlMsg" BackgroundCssClass="displayHide"
DropShadow="true" OkControlID="lblStsFoot" OnOkScript="setFocus()" >
</cc1:ModalPopupExtender>
<asp:Panel ID="pnlMsg" runat="server" CssClass="ErrorPanel" >
<table width="100%">
<tr>
<td >
<asp:Label ID="lblHead" CssClass="lblHead" runat="server"
Text=""></asp:Label>
</td>
</tr>
<tr>
<td >
<table class="tblTableHead" >
<tr >
<td style ="width:4%;">S.No</td>
<td style ="width:21%;">Type</td>
<td style ="width:25%;">Date</td>
<td style ="width:20%;">Amount Type</td>
<td style ="width:15%;">Amount</td>
<td style ="width:15%;">Adjust Amount</td>
</tr>
</table>
<div id="divGridStatus" style="width:100%;max-height:300px;overflow-Y:auto;overflow-X:hidden;" >
<asp:GridView ID="grvStatus" runat="server" Width="100%"
AutoGenerateColumns="false" CssClass="GridViewStyle" GridLines="None" ShowHeader="false" >
<Columns>
<asp:TemplateField >
<ItemTemplate>
<asp:LinkButton ID="lnkSNo" runat="server" CssClass="lbl"
Width="100%" OnClientClick="return false;" Font-Underline="false"
ReadOnly="true" >
<%# ((GridViewRow)Container).RowIndex + 1%>
</asp:LinkButton>
</ItemTemplate>
<ItemStyle Width="4%" />
</asp:TemplateField>
<asp:TemplateField >
<ItemTemplate>
<asp:LinkButton ID="lnkwsid" runat="server" Width="100%" OnClientClick="return false;"
ReadOnly="true" Font-Underline="false"
Text='<%# Bind("wsid") %>' >
</asp:LinkButton>
</ItemTemplate>
<ItemStyle Width="21%" />
</asp:TemplateField>
<asp:TemplateField >
<ItemTemplate>
<asp:LinkButton ID="lnknm" runat="server" Width="100%" OnClientClick="return false;"
ReadOnly="true" Font-Underline="false"
Text='<%# Bind("nm") %>' >
</asp:LinkButton>
</ItemTemplate>
<ItemStyle Width="25%" />
</asp:TemplateField>
<asp:TemplateField >
<ItemTemplate>
<asp:LinkButton ID="lnkgrp1" runat="server" Width="100%" OnClientClick="return false;"
ReadOnly="true" Font-Underline="false" Text='<%# Bind("grp1") %>' >
</asp:LinkButton>
</ItemTemplate>
<ItemStyle Width="20%" />
</asp:TemplateField>
<asp:TemplateField >
<ItemTemplate>
<asp:LinkButton ID="lnkoptid" runat="Server" CssClass="lbl"
Width="100%" OnClientClick="return false;" Font-Underline="false"
ReadOnly="true" Text='<%# Bind("optid") %>' >
</asp:LinkButton>
</ItemTemplate>
<ItemStyle Width="15%" />
</asp:TemplateField>
<asp:TemplateField >
<ItemTemplate>
<asp:LinkButton ID="lnkuid" runat="server"
Width="100%" CssClass="lbl" OnClientClick="return false;" Font-Underline="false"
ReadOnly="true" Text='<%# Bind("uid") %>' >
</asp:LinkButton>
</ItemTemplate>
<ItemStyle Width="15%" />
</asp:TemplateField>
</Columns>
<FooterStyle CssClass="FooterStyle" />
<RowStyle CssClass="RowStyle" />
<EmptyDataRowStyle CssClass="EmptyRowStyle" />
<EmptyDataTemplate>
No Data Found.
</EmptyDataTemplate>
<PagerStyle CssClass="PagerStyle" />
<SelectedRowStyle CssClass="SelectedRowStyle" />
<HeaderStyle CssClass="HeaderStyle" />
<EditRowStyle CssClass="EditRowStyle" />
<AlternatingRowStyle CssClass="AltRowStyle" />
</asp:GridView>
</div>
<table class="tblTableHead" style="padding-left:1%;">
<tr>
<td>
<asp:Label ID="lblStsFoot" runat="server" Text="" ></asp:Label>
</td>
</tr>
</table>
</td>
</tr>
<tr>
<td>
<br />
<%--OnClientClick="return CheckAdjustment();"OnClientClick="ShowWait();"--%>
<asp:Button ID="btnAdjust" runat="server" Text="Done" CssClass="btn" OnClick="btnAdjust_Click"
buttonAction="submitButton" />
<asp:Button ID="btnCancel" runat="server" Text="Cancel" CssClass="btn" OnClick="btnCancel_Click"
buttonAction="submitButton" />
</td>
</tr>
</table>
<br />
</asp:Panel>
</ContentTemplate>
</asp:UpdatePanel>
C# Code
protected void btnShow_Click(object sender, EventArgs e)
{
mpeAdjAmt.Show();
upnlModelPopup.Update();
}
protected void btnAdjust_Click(object sender, EventArgs e)
{
//Code goes here...
mpeAdjAmt.Hide();
upnlModelPopup.Update();
}
protected void btnCancel_Click(object sender, EventArgs e)
{
mpeAdjAmt.Hide();
upnlModelPopup.Update();
}
I'm showing/hiding this panel from code behind.
When i click's on show button first time it works very fine it shows panel proper.
My problem is when i click's on show button second time it doesn't show panel.
If i removed update panel it works fine when we use to show and hide panel from code behind but it starts flicker of panel on page load and works fine .
Can any one tell me what is the problem and how can i solve that.

Answer 1

Try doing
protected void btnShow_Click(object sender, EventArgs e)
{
mpeAdjAmt.Show();
upnlModelPopup.Update();
mpeAdjAmt.BackgroundCssClass="displayHide";
//or
//pnlMsg.CssClass="ErrorPanel";
}
protected void btnAdjust_Click(object sender, EventArgs e)
{
//Code goes here...
mpeAdjAmt.Hide();
upnlModelPopup.Update();
mpeAdjAmt.BackgroundCssClass="displayHide";
//or
//pnlMsg.CssClass="ErrorPanel";
}
protected void btnCancel_Click(object sender, EventArgs e)
{
mpeAdjAmt.Hide();
upnlModelPopup.Update();
mpeAdjAmt.BackgroundCssClass="displayHide";
//or
//pnlMsg.CssClass="ErrorPanel";
}