Passing Values from a "RadGrid" to a "Filtering Template Column"

[Michael Malone]

I'm using the example provided in Filtering Template Columns to use a RadComboBox as a filter instead of the standard TextBox. I have followed the example and it is working as expected. Now I need to know how to pass a value to the RadComboBox so I can dynamically change its DataSource. The DataSource for the RadComboBox should change depending on the value of a column in the RadGrid. Can I somehow access the DataKeyNames of the parent RadGrid to get this value or is there a property of the GridTemplateColumn that I can set in my code-behind? I'm stumped.

protected override void SetupFilterControls(TableCell cell)
{
    RadComboBox rcBox = new RadComboBox();
    rcBox.ID = this.GetType().Name + "ComboBox";
    rcBox.AutoPostBack = true;
    rcBox.DataTextField = this.DataField;
    rcBox.DataValueField = this.DataField;
    rcBox.SelectedIndexChanged += rcBox_SelectedIndexChanged;
    rcBox.Items.Add(new RadComboBoxItem("Show All", ""));
    rcBox.DataSource = DataSource; //<-------- I need to change this DataSource depending on what data is in my RadGrid.
                                    //How can I pass a value here from my aspx page
    rcBox.AppendDataBoundItems = true;
    cell.Controls.Add(rcBox);
}

[Marin]

Hi,

 You have access to the MasterTableView in the SetupFilterControls method from where you can access the datakey names and basically the value of any cell in the grid:

protected override void SetupFilterControls(System.Web.UI.WebControls.TableCell cell)
    {
        var masterTableView = this.Owner;
        masterTableView.DataKeyNames
        masterTableView.DataKeyValues
    }

All the best,
Marin
the Telerik team

[Michael Malone]

Lets say one of the columns is called "DivisionID". How would I retrieve this value from the example you provided?

[Marin]

Hi,

 The value of a cell for a specific row and column can be accessed like this:

protected override void SetupFilterControls(TableCell cell)
    {
        var masterTableView = this.Owner;
        var value = masterTableView.Items[i][this].Text;

    }

or if you have set its data field as a data key name, you can also access it like this:

var keyValue = masterTableView.DataKeyValues[i]["DataKeyName"];

Regards,
Marin
the Telerik team

[Michael Malone]

I've tried both examples and they both give the following error -

"Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index"

<telerik:RadGrid ID="uxEmpGrid" runat="server" AutoGenerateColumns="false" AllowSorting="True"
    GroupingEnabled="true" ShowGroupPanel="true" Skin="Office2007" AlternatingItemStyle-BackColor="#EEEEEE"
    GridLines="None" ShowFooter="true" AllowPaging="true" PageSize="200" AllowFilteringByColumn="true">
    <GroupingSettings ShowUnGroupButton="true" CaseSensitive="false"  />
    <ClientSettings AllowDragToGroup="true"></ClientSettings>
    <MasterTableView DataKeyNames="DivisionID">
        <Columns>
            <telerik:GridBoundColumn DataField="DivisionID" HeaderText="DivisionID" Groupable="false"></telerik:GridBoundColumn>
            <telerik:GridBoundColumn DataField="SAPEmpNum" HeaderText="ID" Groupable="false"></telerik:GridBoundColumn>
            <telerik:GridBoundColumn DataField="FullNameLastNameFirst" HeaderText="Team Member" ></telerik:GridBoundColumn>
            <nu:SAPPositionFilterColumn DataField="SAPPosition" HeaderText="Job Title" UniqueName="SAPPosition">
                <Itemtemplate>
                        <%# Eval("SAPPosition") %>
                </Itemtemplate>
            </nu:SAPPositionFilterColumn>
            <nu:SAPCrewFilterColumn DataField="SAPCrew" HeaderText="Crew" UniqueName="SAPCrew">
                <Itemtemplate>
                        <%# Eval("SAPCrew") %>
                </Itemtemplate>
            </nu:SAPCrewFilterColumn>
            <nu:SAPDepartmentFilterColumn DataField="SAPDepartment" HeaderText="Department" UniqueName="SAPDepartment">
                <Itemtemplate>
                        <%# Eval("SAPDepartment") %>
                </Itemtemplate>
            </nu:SAPDepartmentFilterColumn>
            <nu:SAPSupervisorFilterColumn DataField="SAPSupervisorNameLastNameFirst" HeaderText="Supervisor" UniqueName="SAPSupervisorNameLastNameFirst">
                <Itemtemplate>
                        <%# Eval("SAPSupervisorNameLastNameFirst") %>
                </Itemtemplate>
            </nu:SAPSupervisorFilterColumn>
        </Columns>
    </MasterTableView>
</telerik:RadGrid>

protected override void SetupFilterControls(TableCell cell)

{

    var masterTableView = this.Owner;

      
  //Either one gives an error       

    this.DivisionID = Convert.ToInt32(masterTableView.DataKeyValues[0]["DivisionID"]);

    this.DivisionID = Convert.ToInt32(masterTableView.Items[0][this].Text);

 

 

    RadComboBox rcBox = new RadComboBox();

    rcBox.ID = this.GetType().Name + "ComboBox";

    rcBox.AutoPostBack = true;

    rcBox.DataTextField = this.DataField;

    rcBox.DataValueField = this.DataField;

    rcBox.SelectedIndexChanged += rcBox_SelectedIndexChanged;

    rcBox.Items.Add(new RadComboBoxItem("Show All", ""));           

    rcBox.DataSource = DataSource;

    rcBox.AppendDataBoundItems = true;

    cell.Controls.Add(rcBox);

}

[Marin]

Hi,

 Most likely the error is causes because the grid is not databound yet - and its column (and datakay values) still do not contain any data. Normally the grid first builds all the controls (filter controls, column editors etc.) and then populates them with data. So building a filter control that depends on the data of another column cannot be achieved in this way because the actual data that you need is not yet populated in the grid.
Another option is to add the filter control later in the page life cycle after the grid has been databound (but before it is rendered) and then access the necessary data. One such event is the ItemDataBound event. Of course you can also manually perform a query to the database and extract the necessary data if this is applicable in your case.

All the best,
Marin
the Telerik team

[Michael Malone]

Thanks for the info. I can move the needed data into a DropDownList that is outside of the Grid. How can I pass the the SelectedValue of the DropDownList to my Filter Column?

[Maria Ilieva]

Hello Michael,

You could handle the DropDown SelectedIndexChanged event and manipulate the FilterExpression, similar to this:

<telerik:RadComboBox ID="RadComboBox1" runat="server"  AutoPostBack="true"
           onselectedindexchanged="RadComboBox1_SelectedIndexChanged">
               <Items>
                   <telerik:RadComboBoxItem Text="1" Value="1" />
                   <telerik:RadComboBoxItem Text="2" Value="2" />
               </Items>
           </telerik:RadComboBox>
       <telerik:RadGrid ID="RadGrid1" runat="server" AutoGenerateColumns="false" OnNeedDataSource="RadGrid1_NeedDataSource"
        AllowFilteringByColumn="true" EnableLinqExpressions="false">
           <MasterTableView>
               <Columns>
                   <telerik:GridBoundColumn DataField="ID1" HeaderText="ID1" UniqueName="ID1">
                   </telerik:GridBoundColumn>
                   <telerik:GridBoundColumn DataField="ID2" HeaderText="ID2" UniqueName="ID2">
                   </telerik:GridBoundColumn>
                   <telerik:GridBoundColumn DataField="ID3" HeaderText="ID3" UniqueName="ID3">
                   </telerik:GridBoundColumn>
                   <telerik:GridEditCommandColumn UniqueName="EditColumn">
                   </telerik:GridEditCommandColumn>
               </Columns>
           </MasterTableView>
       </telerik:RadGrid>

C#:

protected void RadGrid1_NeedDataSource(object sender, Telerik.Web.UI.GridNeedDataSourceEventArgs e)
       {
           dynamic data = new[] {
               new { ID1 = "1", ID2 = 11, ID3=111},
               new { ID1 = "2", ID2 = 22, ID3=222}

           };
           RadGrid1.DataSource = data;
       }

       protected void RadComboBox1_SelectedIndexChanged(object sender, Telerik.Web.UI.RadComboBoxSelectedIndexChangedEventArgs e)
       {
           RadGrid1.MasterTableView.FilterExpression = "([ID1] LIKE \'%" + RadComboBox1.SelectedValue + "%\') ";
           GridColumn column = RadGrid1.MasterTableView.GetColumnSafe("ID1");
           column.CurrentFilterFunction = GridKnownFunction.Contains;
           column.CurrentFilterValue = RadComboBox1.SelectedValue;
           RadGrid1.MasterTableView.Rebind();

       }

I hope this helps.

Greetings,
Maria Ilieva
the Telerik team