Radgrid change GridDropDownColumn's datasource based on selection of another GridDropDownColumn in edit mode

[Rui]

Hi,
I have three GridDropDownColumns in my Radgrid:

     <telerik:GridDropDownColumn UniqueName="AddressCountry" ListDataMember="AddressCountry" ColumnEditorID="AddressCountryColumnEditor" HeaderStyle-Width="200"
                                SortExpression="Id" ListTextField="Name"
                                ListValueField ="Id" HeaderText="Country" DataField="CountryId" />


                            <telerik:GridDropDownColumn UniqueName="AddressProvinceState" ListDataMember="AddressProvinceState" ColumnEditorID="AddressProvinceStateColumnEditor" HeaderStyle-Width="200"
                                SortExpression="Id" ListTextField="Name"
                                ListValueField ="Id" HeaderText="Province/State" DataField="ProvinceStateId" />


                            <telerik:GridDropDownColumn UniqueName="AddressCity" ListDataMember="AddressCity" ColumnEditorID="AddressCityColumnEditor" HeaderStyle-Width="200"
                                SortExpression="Id" ListTextField="Name"
                                ListValueField ="Id" HeaderText="City" DataField="CityId" />

What I want to do is when in edit mode, when the selection of Country or ProvinceState dropdown change, the datasource of the sub dropdowns change. What I tried is this:

protected void grid_GridItemCreated(object sender, GridItemEventArgs e)
    {
        if ((e.Item is GridEditableItem) && (e.Item.IsInEditMode))
        {

            GridEditableItem edititem = (GridEditableItem)e.Item;
            int LocationId = Convert.ToInt32(edititem.GetDataKeyValue("LocationId"));
            DataSet dsAddress = somefunction(LocationId);

            list1.DataSource = dsAddress.Tables["AddressProvinceState"];
            list1.DataTextField = "Name";
            list1.DataValueField = "Id";
            list1.DataBind();
            RadComboBox list2 = (RadComboBox)edititem["AddressCity"].Controls[0];
            list2.DataSource = dsAddress.Tables["AddressCity"];
            list2.DataTextField = "Name";
            list2.DataValueField = "Id";
            list2.DataBind();

            list.SelectedIndexChanged += new RadComboBoxSelectedIndexChangedEventHandler(list_SelectedIndexChanged);
            list.AutoPostBack = true;

            list1.SelectedIndexChanged += new RadComboBoxSelectedIndexChangedEventHandler(list1_SelectedIndexChanged);
            list1.AutoPostBack = true;
        }
    }

private void list_SelectedIndexChanged(object sender, RadComboBoxSelectedIndexChangedEventArgs e)
    {

        RadComboBox list = (RadComboBox)sender;
        GridDataItem editItem = (GridDataItem)list.NamingContainer;
        GridEditManager editMan = editItem.EditManager;
        GridDropDownListColumnEditor editor1 = editMan.GetColumnEditor("AddressProvinceState") as GridDropDownListColumnEditor;
        GridDropDownListColumnEditor editor2 = editMan.GetColumnEditor("AddressCity") as GridDropDownListColumnEditor;




        DataTable dtProvinceState = ProvinceForCountry(Convert.ToInt32(list.SelectedValue));
        DataTable dtCity = CityForProvince(Convert.ToInt32(dtProvinceState.Rows[0]["Id"]));

        editor1.DataSource = dtProvinceState;
        editor1.DataTextField = "Name";
        editor1.DataValueField = "Id";
        editor1.DataBind();
        editor2.DataSource = dtCity;
        editor2.DataTextField = "Name";
        editor2.DataValueField = "Id";
        editor2.DataBind();

    }


    private void list1_SelectedIndexChanged(object sender, RadComboBoxSelectedIndexChangedEventArgs e)
    {

        RadComboBox list = (RadComboBox)sender;
        GridEditFormItem editItem = (GridEditFormItem)list.NamingContainer;
        GridEditManager editMan = editItem.EditManager;
        GridDropDownListColumnEditor editor = editMan.GetColumnEditor("AddressCity") as GridDropDownListColumnEditor;



        DataTable dtCity = CityForProvince (Convert.ToInt32(list.SelectedValue));
        editor.DataSource = dtCity;
        editor.DataTextField = "Name";
        editor.DataValueField = "Id";
        editor.DataBind();

    }

the tables are retrieved correctly, but when I do databind for the dropdown, it doesn't bind with the new tables, still bind with the old ones.
Can I get some help for this?
Thanks

[Princy]

Hi Rui,

Im not sure about your requirements.Below is a code snippet on changing one RadcomboBox value when another RadComboBox value changes,using GridTemplateColumn.Here the DatasourceId for the RadComboBox is changed on the SelectedIndexChanged event.

ASPX:

<telerik:RadGrid ID="RadGrid1" runat="server" OnItemCreated="RadGrid1_ItemCreated" AutoGenerateEditColumn="true">
    <MasterTableView DataKeyNames="OrderID">
        <Columns>
            <telerik:GridTemplateColumn HeaderText="OrderID">
                <ItemTemplate>
                    <%# Eval("OrderID")%>
                </ItemTemplate>
                <EditItemTemplate>
                    <telerik:RadComboBox ID="RadCombobox1" runat="server">
                    </telerik:RadComboBox>
                </EditItemTemplate>
            </telerik:GridTemplateColumn>
            <telerik:GridTemplateColumn HeaderText="OrderID">
                <ItemTemplate>
                    <%# Eval("OrderID")%>
                </ItemTemplate>
                <EditItemTemplate>
                    <telerik:RadComboBox ID="RadCombobox2" runat="server">
                    </telerik:RadComboBox>
                </EditItemTemplate>
            </telerik:GridTemplateColumn>
        </Columns>
    </MasterTableView>
</telerik:RadGrid>

C#:

protected void RadGrid1_ItemCreated(object sender, Telerik.Web.UI.GridItemEventArgs e)
{
    if ((e.Item is GridEditableItem) && (e.Item.IsInEditMode))
    {
        GridEditableItem edititem = (GridEditableItem)e.Item;

        RadComboBox list = (RadComboBox)edititem.FindControl("RadCombobox1");
        list.DataSourceID = "SqlDataSource1";
        list.DataTextField = "OrderID";
        list.DataValueField = "OrderID";
        list.DataBind();

        RadComboBox list1 = (RadComboBox)edititem.FindControl("RadCombobox2");
        list1.DataSourceID = "SqlDataSource1";
        list1.DataTextField = "OrderID";
        list1.DataValueField = "OrderID";
        list1.DataBind();

        list.AutoPostBack = true;
        list.SelectedIndexChanged +=new RadComboBoxSelectedIndexChangedEventHandler(list_SelectedIndexChanged);
    }
}
private void list_SelectedIndexChanged(object sender, RadComboBoxSelectedIndexChangedEventArgs e)
{
    RadComboBox list = (RadComboBox)sender;
    GridEditableItem editItem = (GridEditableItem)list.NamingContainer;
    RadComboBox list1 = (RadComboBox)editItem.FindControl("RadCombobox2");
    list1.DataSourceID = "SqlDataSource2";  //Changing the DataSource
    list1.DataTextField = "OrderID";
    list1.DataValueField = "ShipCity";
    list1.DataBind();
}

Thanks,
Princy

[Rui]

Hi Princy,

Thanks, the datasource does the binding now, guess it just doesn't work with GridDropDownColumn.
But, how do I bind the selected value to my table  when I do update in my radgrid? 
And also, the radgrid is binding those columns by the CountryId, ProvinceId and CityId. But I want to display the "name" in view mode. The "name" is a column in the datasource table of the combobox in edit mode. How should I display that in view mode?
Thanks for the help

[Princy]

Hi Rui,

To display the "name" in the view mode,please try the following code snippet.

ASPX:

<telerik:GridTemplateColumn>
<ItemTemplate>
   <asp:Label ID="Label1" runat="server" ></asp:Label>
 </ItemTemplate>
 <EditItemTemplate>
   <telerik:RadComboBox ID="RadCombobox1" runat="server">
   </telerik:RadComboBox>
 </EditItemTemplate>
</telerik:GridTemplateColumn>

C#:

protected void RadGrid1_ItemDataBound(object sender, GridItemEventArgs e)
   {
       if (e.Item is GridDataItem)
       {
           GridDataItem data = (GridDataItem)e.Item;
           Label labeltemplate = (Label)data.FindControl("Label1"); //Access the label in the template column in view mode
           // query to get the "name" column from datasource
           labeltemplate.Text = "name"; //set it to label text
       }
   }

Thanks,
Princy

[Jesús]

And what have I do with the same scenario, but in batch edit mode?

[Viktor Tachev]

Hi,

Using cascading dropdown controls is not available for Batch edit mode out of the box. However, there is a code-library that illustrates how you can implement the behavior.

Note that the code-library illustrates a custom scenario. You should test it to see how it works for you and apply adjustments if necessary.

• http://www.telerik.com/support/code-library/batch-editing-extensions---related-radcomboboxes-and-validation

Regards,
Viktor Tachev
Telerik