[Solved] Cannot edit radgrid in webusercontrol

[Jon]

I have a radgrid which has user control edit form (webusercontrol), inside which is another radgrid.  In short, both grids have a master/detail relationship.  At the moment, I use dataset as the data source, but bind it in the appropriate NeedDataSource event.

I want to commit changes to master/detail records in a single transaction, if there's a way to do this with a hierachy, I'm all ears.

When I edit a row in the master grid, webusercontrol appears, showing columns from selected row.  Grid inside webusercontrol correctly shows related detail rows.  But as soon as I click Edit, all rows disappear and grid says there are no records to display.  This happens when I click Refresh as well.

I put a breakpoint in detail grid's NeedDataSource event, which vs hits.  I checked there are data in the dataset.

I'm not loading user control dynamically.  Same webusercontrol declared in the grid is used for insert and edit.  I temporarily removed ajax manager to focus on the problem.

I already spent a day reading Telerik's extensive docs, demos and forums.  I googled, yahooed, even binged, but search results point back to Telerik site anyway. 

Any help is much appreciated.

Master

<telerik:RadGrid ID="rgHead" runat="server" ShowStatusBar="True" AutoGenerateColumns="False"
    AllowSorting="True"  AllowPaging="True"
    GridLines="None" OnPreRender="rgHead_PreRender" OnNeedDataSource="rgHead_NeedDataSource"
    OnUpdateCommand="rgHead_UpdateCommand" OnInsertCommand="rgHead_InsertCommand"
    OnDeleteCommand="rgHead_DeleteCommand"
    OnItemCommand="rgHead_ItemCommand" onitemdatabound="rgHead_ItemDataBound">
    <MasterTableView AllowSorting="True" DataKeyNames="RefNo" CommandItemDisplay="Top" Name="Head">
        <Columns>
            <telerik:GridButtonColumn Text="Delete" CommandName="Delete"
                UniqueName="DeleteCommandColumn">
            </telerik:GridButtonColumn>
            <telerik:GridTemplateColumn DataField="RefNo" SortExpression="RefNo" UniqueName="RefNo">
                <EditItemTemplate>
                    <asp:TextBox ID="Textbox1" runat="server" Text='<%# Bind("RefNo") %>'></asp:TextBox>
                </EditItemTemplate>
                <ItemTemplate>
                    <asp:Label ID="Label1" runat="server" Text='<%# Eval("RefNo") %>'></asp:Label>
                </ItemTemplate>
            </telerik:GridTemplateColumn>
            <telerik:GridBoundColumn DataField="Description"
                ReadOnly="True" UniqueName="Description" HeaderText="Description">
            </telerik:GridBoundColumn>
            <telerik:GridBoundColumn DataField="Rate"
                ReadOnly="True" UniqueName="Rate" HeaderText="Rate">
            </telerik:GridBoundColumn>
            <telerik:GridBoundColumn DataField="Active"
                ReadOnly="True" UniqueName="Active" HeaderText="Active"
                DataType="System.Boolean">
            </telerik:GridBoundColumn>
            <telerik:GridBoundColumn DataField="LastUpdateDate"
                UniqueName="LastUpdateDate" HeaderText="Last Updated">
            </telerik:GridBoundColumn>
            <telerik:GridEditCommandColumn UniqueName="EditCommandColumn">
            </telerik:GridEditCommandColumn>
        </Columns>
        <EditFormSettings UserControlName="~/Controls/DetailControl.ascx" EditFormType="WebUserControl">
            <EditColumn UniqueName="EditCommandColumn1">
            </EditColumn>
        </EditFormSettings>
        <PagerStyle PageSizeControlType="RadComboBox"></PagerStyle>
</telerik:RadGrid>

protected void rgHead_NeedDataSource(object sender, GridNeedDataSourceEventArgs e)
{
    rgHead.DataSource = ds.Tables["tblHead"];
}

Detail

<telerik:RadGrid ID="rgItems" runat="server" AllowSorting="True" AutoGenerateColumns="False"
    CellSpacing="0" GridLines="None" OnNeedDataSource="rgItems_NeedDataSource" Width="70%"
    OnDeleteCommand="rgItems_DeleteCommand" OnInsertCommand="rgItems_InsertCommand"
    OnItemCommand="rgItems_ItemCommand" OnUpdateCommand="rgItems_UpdateCommand"
    OnItemDataBound="rgItems_ItemDataBound">
    <MasterTableView CommandItemDisplay="Top" ClientDataKeyNames="ItemNo" DataKeyNames="ItemNo" EditMode="EditForms">
        <RowIndicatorColumn Visible="True">
        </RowIndicatorColumn>
        <CommandItemSettings ExportToPdfText="Export to PDF"></CommandItemSettings>
        <ExpandCollapseColumn Visible="True">
            <HeaderStyle Width="20px"></HeaderStyle>
        </ExpandCollapseColumn>
        <Columns>
            <telerik:GridButtonColumn CommandName="DeleteItem"
                Text="Delete" UniqueName="DeleteColumn">
            </telerik:GridButtonColumn>
            <telerik:GridBoundColumn DataField="ItemNo"
                HeaderText="Item No" UniqueName="ItemNo">
            </telerik:GridBoundColumn>
            <telerik:GridBoundColumn DataField="DiscountRate"
                HeaderText="Discount Rate (%)" UniqueName="DiscountRate">
            </telerik:GridBoundColumn>
            <telerik:GridEditCommandColumn UniqueName="EditCommandColumn2">
            </telerik:GridEditCommandColumn>
        </Columns>
        <EditFormSettings>
            <EditColumn UniqueName="EditCommandColumn2">
            </EditColumn>
        </EditFormSettings>
        <PagerStyle PageSizeControlType="RadComboBox"></PagerStyle>
    </MasterTableView>
    <PagerStyle PageSizeControlType="RadComboBox"></PagerStyle>
    <FilterMenu EnableImageSprites="False">
    </FilterMenu>
</telerik:RadGrid>

protected void rgItems_NeedDataSource(object sender, GridNeedDataSourceEventArgs e)
{
    rgItems.DataSource = ds.Tables["tblDetails"].Select("RefNo='" + (string)DataBinder.Eval(DataItem, "RefNo") + "'");
}

[Andrey]

Hello,

If you want to save the changes from both RadGrid controls in a single transaction you should do this manually because RadGrid does not provide built-in support for transactions. You could check this Code-Project article for more information on using transactions with data-bound controls.

About your problem, could you share your full page source code along with the code-behind file content? Thus all the people who want to help you will have better understanding of your case.

Regards,
Andrey
Telerik

[Jon]

Andrey, thanks for taking the time to reply.

protected void rgItems_NeedDataSource(object sender, GridNeedDataSourceEventArgs e)
{
    rgItems.DataSource = ds.Tables["tblDetails"].Select("RefNo='" + (string)DataBinder.Eval(DataItem, "RefNo") + "'");
}

The problem was DataItem.  This is passed by radgrid that contains the webusercontrol, but as I eventually discovered, DataItem is null on subsequent postbacks, like if I click Add or Edit in the inner grid!  I hate wasting time on nitty gritty.  I wonder if using mvc has obstacles like this, or has it got it's own problems.

I spent a long day trying to fix this error.  Then the next morning, it just came to me, sigh.

[Andrey]

Hi,

Yes, the DataItem is initialized only during the DataBind stage of the control. On a postback if there was no change to the data RadGrid restores its data from the ViewState and that is why the DataItem is null.

ASP.NET MVC is a different architecture and some things are done easier than the Web Forms approach, however, almost each time a new design is required and a new set of control, since Web Forms controls does not work as expected in MVC scenario.

Regards,
Andrey
Telerik