Could not Update Text box control values - asp.net

Question

I am really frustrated to find a solution for my scenario. I have two gird when First grid is used show the shop information and the second grid is used to edit the offers related to the shop information. When the users edit the second grid i will just update the text box values related to the grid selection row. in my code behind file i can see the data fetching from the grid and assigning into the text boxes but when the function call (imgEdit_click) finished the page does not show the values. Editing functionality can be done in many ways but my scenario is what i explained earlier . I have the checked page there is no Postback action has been called after the method I could not find the solution can anyone help me to figure it out.
Following are my source and code behind codes.
My design Source :
<div class="field">
<asp:TextBox ID="txtareaOfferDesc" runat="server" TextMode="MultiLine" ></asp:TextBox>
</div>
<div class="field">
<asp:TextBox ID="txtTimeStarts" runat="server" CssClass="textfield"></asp:TextBox>
<cc1:CalendarExtender
ID="CalendarExtender2"
runat="server"
TargetControlID="txtTimeStarts"
CssClass="CalendarCSS">
</cc1:CalendarExtender>
<div class="datefld">
<label class="name">Offer end date/time (optional)</label>
<div class="field">
<asp:TextBox ID="txtTimeEnd" runat="server" CssClass="textfield"></asp:TextBox>
<cc1:CalendarExtender ID="CalendarExtender4" runat="server" TargetControlID="txtTimeEnd"
CssClass="CalendarCSS">
</cc1:CalendarExtender> `
<asp:GridView ID="gvShopDeal" runat="server" AutoGenerateColumns="false"
CssClass="tblexistoffer" DataKeyNames="ShopID" AllowPaging="True"
AllowSorting="True">
<Columns>
<asp:TemplateField>
<HeaderTemplate >
<asp:CheckBox ID="chkHeader" runat="server" />
<asp:Label ID="lblSelectAll" Text="Select All" runat="server"></asp:Label>
</HeaderTemplate>
<ItemTemplate >
<asp:CheckBox ID="chkRow" runat="server" />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="ShopID" HeaderStyle-Width="10%" HeaderText="Shop ID" />
<asp:BoundField DataField="ShopName" HeaderStyle-Width="40%" HeaderText="Shop Name" />
<asp:BoundField DataField="Street" HeaderStyle-Width="40%" HeaderText="Street" />
<asp:BoundField DataField="City" HeaderText ="City" />
</Columns>
</asp:GridView>
<asp:Button ID="btnCreateDeal" runat="server" Text="Create Offer"
CssClass="grnbtn" OnClientClick="return CheckDealValidation(this)" onclick="btnCreateDeal_Click"></asp:Button>
<asp:Button ID="btnDefCancel" runat="server" Text="Cancel" CssClass="greybtn"></asp:Button>
<asp:UpdatePanel ID="UpdateExistingOffer" runat="server">
<ContentTemplate>
<asp:GridView ID="gvExistingOffers" runat="server" CssClass="tblexistoffer"
AutoGenerateColumns="false" DataKeyNames="OfferID" AllowPaging="True"
AllowSorting="True">
<Columns>
<asp:BoundField DataField="OfferID" HeaderText="OfferID" />
<asp:BoundField DataField="Description" HeaderText="OfferName" />
<asp:BoundField DataField="Status" HeaderText="Status" />
<asp:BoundField DataField="OfferType" HeaderText="OfferType" />
<asp:BoundField DataField="StartDate" HeaderText="StartDate">
<ItemStyle CssClass="Hide" />
<HeaderStyle CssClass="Hide" />
</asp:BoundField>
<asp:BoundField DataField="EndDate" HeaderText="EndDate" >
<ItemStyle CssClass="Hide" />
<HeaderStyle CssClass="Hide" />
</asp:BoundField>
<asp:TemplateField HeaderText="Edit" HeaderStyle-Width="5%">
<ItemTemplate>
<asp:ImageButton ID="imgbtnEdit" ImageUrl="~/Merchant/images/edit.jpg" runat="server" Width="25" Height="25" onclick="imgbtnEdit_Click" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</ContentTemplate>
</asp:UpdatePanel>
Code Behind File :
protected void imgbtnEdit_Click(object sender, ImageClickEventArgs e)
{
ImageButton btndetails = sender as ImageButton;
GridViewRow gvrow = (GridViewRow)btndetails.NamingContainer;
fferIDForShop = Convert.ToInt32(gvExistingOffers.DataKeys[gvrow.RowIndex].Value);
ShopList objShopID = ShopService.GetShopID(OfferIDForShop);
(txtareaOfferDesc.Text) = gvrow.Cells[1].Text.Trim();
txtTimeStarts.Text = gvrow.Cells[4].Text;
txtTimeEnd.Text = gvrow.Cells[5].Text;
}
Thanks
Vijay

Answer 1

Issue is because textboxes are out of Update Panel, So just put everything in update panel it will start functioning or just comment out update panel and then try the same thing.