can't see asp.net gridview on page load
===

I have a gridview that won't show on page load.  The gridview is inside of some asp:Panels which are inside of an update panel.  I stepped through the code, so I know the gridview has rows of data.  If I move the gridview outside of the panels and update panels, then it will show up with data.  Does anybody know why it doesn't work as it sits below, inside of the panels and update panels?  

        <%@ Page Language="VB" AutoEventWireup="false" EnableEventValidation="false" MasterPageFile="~/CTPublic.master" CodeFile="Tank.aspx.vb" Inherits="CargoTank_Internal_Tank" %>

 <asp:Content ID="CargoTank" ContentPlaceHolderID="CPHBody" Runat="Server">

    <div style="padding-top:9px; width:100%; min-width:800px; " >
        <asp:UpdatePanel ID="udpTank" runat="server" >
        <ContentTemplate>
                    <ajaxToolkit:RoundedCornersExtender runat="server" BorderColor="#3260a0"   Corners="All" Radius="5" Color="#98B9C9"  TargetControlID="pnlTank" ID="ajRCEpnlTank" ></ajaxToolkit:RoundedCornersExtender>

             <asp:Panel runat="server" BackColor="#ecece7"  Width="95%"  ID="pnlTank" >
                   
                 <div >
                <div style="float:left; width:70%; background-color:#98B9C9; height:19px;">Tanks</div>
                <div style="float:right; width:30%; height:19px;background-color:#98B9C9; text-align:right">
                    <asp:Button ID="btnAddNewTank" style="background:transparent; border:0px;" runat="server" Font-Underline="true"   size="1" Font-Bold=true text="Add New" /> 

                 </div> 
                <div style="padding-top:19px;"></div>
                </div>   
                <div style="width:100%;">
                    <table width="100%">
                        <tr>
                            <td colspan="6" class="tdheaderbar">Search Tanks
                            </td>
                        </tr>
                        <tr>
                            <td>CT #</td>
                            <td><asp:TextBox runat="server" ID="txtCTNumber" ></asp:TextBox></td>
                            <td>Serial #</td>
                            <td><asp:TextBox runat="server" ID="txtSerialNumber" MaxLength="17"></asp:TextBox></td>
                            <td>City</td>
                            <td><asp:TextBox runat="server" ID="txtCity"></asp:TextBox></td>

                        </tr>
                        <tr>
                             <td>Capacity</td>
                            <td><asp:TextBox runat="server" ID="txtCapacity"></asp:TextBox></td>
                           <td>Unit #</td>
                            <td><asp:TextBox runat="server" ID="txtUnitNumber"></asp:TextBox></td>
                            <td>License State</td>
                            <td><asp:DropDownList EnableViewState="true" runat="server" ID="ddlState" DataSourceID="linqStates" 
                                   Width="156px" DataTextField="StateText" DataValueField="StateID"></asp:DropDownList>
                                <asp:LinqDataSource ID="linqStates" runat="server" 
                                    ContextTypeName="DataClassesDataContext" TableName="States">
                                </asp:LinqDataSource>
                            </td>

                      </tr>
                         <tr>
                             <td>Tank Type</td>
                            <td>
                                <asp:DropDownList runat="server" ID="ddlTankType"  Width="156px"
                                     ></asp:DropDownList>
 
                            </td> 
                            <td>Compartment</td>
                            <td><asp:TextBox runat="server" ID="txtCompartment"></asp:TextBox></td>
                             <td>License #</td>
                            <td><asp:TextBox runat="server" ID="txtLicenseNumber"></asp:TextBox></td>
                      </tr>
                          <tr>
                             <td>Manufacturer</td>
                            <td colspan="2">
                                <asp:DropDownList runat="server" ID="ddlManufacturer"  
                                     ></asp:DropDownList>
                                
                            </td> 
                             
                                           
                           <td><asp:CheckBox runat="server" ID="chkNoLogIn" Text="No Log In Associated" /></td>
                           <td></td> <td></td> 
                       </tr>
                       <tr><td>Company</td>
                            <td colspan="5"> <asp:DropDownList runat="server" ID="ddlCompany" ></asp:DropDownList></td>    
                     </tr>  
                     <tr>
                        <td colspan="3">
                        </td>
                        <td><asp:Button runat="server" ID="btnSearch" Text="Search" /></td>
                      </tr>
                    </table>
                </div>
 
            </asp:Panel>
       </ContentTemplate>
        <Triggers>
        <asp:AsyncPostBackTrigger ControlID="btnSearch" EventName="Click" />
        </Triggers>  
      </asp:UpdatePanel>
      <br />
      
          <div style="padding-top:9px; width:100%; " id="divTankDetail" runat="server">
        <asp:UpdatePanel ID="updTankDetail" runat="server"  >
        <ContentTemplate>
            <ajaxToolkit:DropShadowExtender runat="server" ID="dsetank" TargetControlID="pnlTankDetail" TrackPosition="true" BehaviorID="pnlTankDetailHeader"></ajaxToolkit:DropShadowExtender>
            <ajaxToolkit:DragPanelExtender runat="server" ID="dpeTankDetail" TargetControlID="pnlTankDetail" DragHandleID="pnlTankDetailHeader"></ajaxToolkit:DragPanelExtender>
            <asp:Panel CssClass="TankpopupPosition" BackColor="LightBlue" Visible="false" runat="server" BorderColor="#3260a0" BorderWidth="2px"  Width="801px"  ID="pnlTankDetail" >
                   <asp:Panel runat="server" BorderColor="#3260a0" BorderWidth="1px"  Width="800px"  ID="pnlTankDetailHeader">
                 <div  >
                <div style="float:left; width:90%; background-color:#98B9C9; height:19px;">Tank Detail</div>
                <div style="float:right; width:10%; border-right-width:2px; border-width:1px; border-color:#3260a0; height:19px;background-color:#98B9C9; text-align:right">
                    <asp:Button ID="btnClose" style="background:transparent; border:0px;" runat="server"   size="1" Font-Bold=true text="X" />&nbsp;
                </div> 
                
                <div style="padding-top:19px;"></div>
                </div>  
                </asp:Panel>
                   <asp:Panel  runat="server"  Width="800px"  ID="pnlTankDetailBody">
                    <div id="divTankDetailbody" runat="server" style="width:100%"  >
                     <br />
                     <table width="100%">
                        <tr>
                            <td>CT #</td>
                            <td><asp:TextBox TabIndex="10" runat="server" BorderStyle="Inset" BorderColor="White" BorderWidth="2px" BackColor="Transparent" ID="txtCTNum" ReadOnly="true" ></asp:TextBox>
                            <asp:Label ID="lblCTNumber" runat="server" Text="*"></asp:Label>&nbsp</td>
                            <td>Serial #</td>
                            <td><asp:TextBox TabIndex="14" runat="server" BorderStyle="Inset" BorderColor="White" BorderWidth="2px" ID="txtSeriaNum" MaxLength="17"></asp:TextBox>
                            <asp:Label ID="lblSerialNumber" runat="server" Text="*"></asp:Label>&nbsp</td>
                            <td>City</td>
                            <td><asp:TextBox runat="server" TabIndex="18" BorderStyle="Inset" BorderColor="White" BorderWidth="2px" ID="txtOrignatedCity"></asp:TextBox></td>
                        </tr>
                        <tr>
                            <td>Capacity</td>
                            <td><asp:TextBox TabIndex="11" runat="server" BorderStyle="Inset" BorderColor="White" BorderWidth="2px" ID="txtTanktCapacity"></asp:TextBox>
                            <asp:Label ID="lblCapacity" runat="server" Text="*"></asp:Label>&nbsp</td>
                             <td>Compartment</td>
                            <td><asp:TextBox runat="server" TabIndex="15" ID="txtCompartment2" BorderStyle="Inset" BorderColor="White" BorderWidth="2px"></asp:TextBox>
                          <asp:Label ID="lblCompartment" runat="server" Text="*"></asp:Label>&nbsp</td>
                                                                              
                                                        <td>License #</td>
                            <td><asp:TextBox runat="server" BorderStyle="Inset" TabIndex="19" BorderColor="White" BorderWidth="2px" ID="txtLicenseNum"></asp:TextBox></td>
                      </tr>
                         <tr>
                                                      <td>Tank Type</td>
                            <td>
                                <asp:DropDownList runat="server" TabIndex="12" ID="ddlTankType2" Width="156px" 
                                     DataTextField="TankTypeName" 
                                    DataValueField="TankTypeName"></asp:DropDownList><asp:Label ID="lblTankType" runat="server" Text="*"></asp:Label>&nbsp
                             </td> 
                            <td>Unit #</td>
                            <td><asp:TextBox runat="server" TabIndex="16" BorderStyle="Inset" BorderColor="White" BorderWidth="2px" ID="txtUnitNum"></asp:TextBox></td>

                            <td>License State</td>
                            <td> 
                                <asp:DropDownList EnableViewState="true" Width="156px" TabIndex="20"  runat="server" ID="ddlLicenseState" DataSourceID="linqStates" 
                                    DataTextField="StateText" DataValueField="StateID"></asp:DropDownList>                                
                              

                                <asp:LinqDataSource ID="LinqDataSource1" runat="server" 
                                    ContextTypeName="DataClassesDataContext" TableName="States">
                                </asp:LinqDataSource>
                            </td>

                      </tr>
                      <tr>
                            <td>Manufacturer</td>
                            <td colspan="1">
                                <asp:DropDownList runat="server" TabIndex="13" ID="ddlManufacturer2"  
                                   >
                                     </asp:DropDownList><asp:Label ID="lblManufacturer" runat="server" Text="*"></asp:Label>&nbsp
                             </td> 
                            <td>Company</td>
                            <td colspan="3"> <asp:DropDownList runat="server" TabIndex="17" ID="ddlCompany2" ></asp:DropDownList><asp:Label ID="lblCompany2" runat="server" Text="*"></asp:Label></td>      
                         
                       </tr>
                      <tr>
                        <td colspan="6" align="center"><br />
                            <asp:Label ID="lblChangeOwnership" Font-Size="Medium" runat="server"></asp:Label>
                            <br />
                            <asp:CheckBox ID="chkChangeOwnership" runat="server" Text="Changing ownership" ForeColor="Red" Font-Bold="true" />
                        </td>
                      </tr>
                      <tr>
                        <td colspan="6" align="center">
                            <br />
                         <asp:Button runat="server" ID="btnAdd" TabIndex="21" Text="Add" Width="60px" /> 
                         <asp:Button runat="server" ID="btnUpdate" TabIndex="22" Text="Update" Width="60px" /> 
                         <asp:Button runat="server" ID="btnChangeOnwership" TabIndex="23" Text="Change" Width="60px" /> 
                         <asp:Button runat="server" ID="btnCancel" TabIndex="24" Text="Cancel" Width="60px"  />
                         <br /><br />
                            <asp:GridView ID="grdTanks" runat="server" AllowPaging="True" 
                                AutoGenerateColumns="False" BackColor="Transparent" GridLines="None" 
                                PagerSettings-Mode="NumericFirstLast" PageSize="10" 
                                RowStyle-HorizontalAlign="left" Width="100%">
                                <AlternatingRowStyle CssClass="alternateItemStyle" />
                                <HeaderStyle CssClass="headerStyle" />
                                <PagerSettings Mode="NumericFirstLast" />
                                <RowStyle CssClass="itemStyle" />
                                <Columns>
                                    <asp:BoundField DataField="CargoTankID" HeaderText="CT #" InsertVisible="False" 
                                        ReadOnly="True" SortExpression="CargoTankID" />
                                    <asp:BoundField DataField="CompanyID" HeaderText="CompanyID" 
                                        SortExpression="CompanyID" Visible="false" />
                                    <asp:BoundField DataField="OriginatedCity" HeaderText="OriginatedCity" 
                                        SortExpression="OriginatedCity" Visible="false" />
                                    <asp:BoundField DataField="LicenseNumber" HeaderText="LicenseNumber" 
                                        SortExpression="LicenseNumber" Visible="false" />
                                    <asp:BoundField DataField="LicenseState" HeaderText="LicenseState" 
                                        SortExpression="LicenseState" Visible="false" />
                                    <asp:BoundField DataField="UnitNumber" HeaderText="Unit Number" 
                                        SortExpression="UnitNumber" Visible="false" />
                                    <asp:TemplateField HeaderText="Company">
                                        <ItemTemplate>
                                            <%#DisplayCompanyName(Eval("CompanyID"))%>
                                        </ItemTemplate>
                                    </asp:TemplateField>
                                    <asp:BoundField DataField="SerialNumber" HeaderText="Serial Number" 
                                        SortExpression="SerialNumber" />
                                    <asp:BoundField DataField="Capacity" HeaderText="Capacity" 
                                        SortExpression="Capacity" />
                                    <asp:TemplateField HeaderText="Manufacturer">
                                        <ItemTemplate>
                                            <%#DisplayManufacturer(Eval("ManufacturerID"))%>
                                        </ItemTemplate>
                                    </asp:TemplateField>
                                    <asp:BoundField DataField="TankType" HeaderText="Tank Type" 
                                        SortExpression="TankType" Visible="false" />
                                    <asp:BoundField DataField="Compartment" HeaderText="Compartment" 
                                        SortExpression="Compartment" Visible="false" />
                                    <asp:BoundField DataField="DecalID" HeaderText="DecalID" 
                                        SortExpression="DecalID" Visible="false" />
                                    <asp:TemplateField HeaderText="Decal Status">
                                        <ItemTemplate>
                                            <%#DisplayTestLink(Eval("CargoTankID"))%>
                                        </ItemTemplate>
                                    </asp:TemplateField>
                                </Columns>
                            </asp:GridView>
                         </td>

                      </tr>
                    </table>
                    
                </div>
                </asp:Panel>
            </asp:Panel>
       </ContentTemplate>
        <Triggers>
                <asp:AsyncPostBackTrigger ControlID="btnSearch" EventName="Click" />

        </Triggers>  
      </asp:UpdatePanel>
</div>

</div>





</asp:Content>
