Dynamically adding controls in the columns in the grid

[VEDA VIDVA NARAYANAN SATTANATHAN]

Hi,
I am currently trying to create controls inside a column of the grid view dynamically. My requirement is like i want to create textbox or combo box and bind it into the column depending on the condition. Is it possible to have textbox and combobox in the same column?

Can you please enlighten us with some sample code?

Thanks in advance,
Veda

[Martin Vasilev]

Hi VEDA VIDVA NARAYANAN SATTANATHAN,

Thank you for the question.

You could customize every cell in RadGridView through the CellFormating and ViewCellFormating events.

To add RadComboBoxElement in data cells you can use CellFormating. Please, review the code-block below as example:
 

void radGridView1_CellFormatting(object sender, CellFormattingEventArgs e)
{
    if (e.CellElement.ColumnIndex == 0 &&
        (float)this.radGridView1.Rows[e.CellElement.RowIndex].Cells["Discount"].Value == 0)
    {
        e.CellElement.Children.Add(new RadComboBoxElement());
    }
}

You can find more information on these in the provided documentation.

Do not hesitate to contact me again if you have other questions.

Best wishes,
Martin Vasilev
the Telerik team

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[Mike]

I've added a RadComboBoxElement to a  Parent GridViewTextBoxColumn.  I want to populate with values from a custom object.
How do you add items to the RadComboBoxElement?

 

 

 

[Martin Vasilev]

Hi Mike,

Thank you writing.

You can add items to the RadComboBoxEditor in the EditorRequiered event. Please, review the code block below as example:
 

void radGridView1_EditorRequired(object sender, EditorRequiredEventArgs e)
{
    RadComboBoxEditor comboEditor = e.Editor as RadComboBoxEditor;

    if (comboEditor != null)
    {
        comboEditor.Items.Clear();

        for (int i = 0; i < (int)this.radGridView1.CurrentRow.Cells[2].Value; i++)
        {
            comboEditor.Items.Add(new RadComboBoxItem(String.Format("item{0}", i+1)));
        }

        comboEditor.SelectedIndex = 0;
    }
}

Hope this helps. Write me back if you have other questions.

Kind regards,
Martin Vasilev
the Telerik team

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[Geert]

This gives a problem in my code:

this is my code to set in the first row comboboxes

private void radGridView1_CellFormatting(object sender, CellFormattingEventArgs e)
        {
            if (e.CellElement.ColumnInfo is GridViewDataColumn && !(e.CellElement.RowElement is GridTableHeaderRowElement))
            {
                if (e.CellElement.RowIndex == 0)
                {
                    if (e.CellElement.Children.Count > 0)
                        return;

                    RadComboBoxEditor element = new RadComboBoxEditor();
                    element.Items.Add(new RadComboBoxItem("test"));
                    element.Items.Add(new RadComboBoxItem("test"));
                    element.Items.Add(new RadComboBoxItem("test"));
                    element.Items.Add(new RadComboBoxItem("test"));
                    element.Items.Add(new RadComboBoxItem("test"));
                    e.CellElement.Children.Add(element);
                    // apply theme to the progress bar
                    ApplyThemeToElement(element, "ControlDefault");

                }
            }

        }
        private void ApplyThemeToElement(RadItem item, string themeName)
        {
            DefaultStyleBuilder builder =
                    ThemeResolutionService.GetStyleSheetBuilder(item, themeName) as DefaultStyleBuilder;
            if (builder != null)
                //clone because control might modify it later
                item.Style = new XmlStyleSheet(builder.Style).GetStyleSheet();
        }

I've tried to put some items in the combobox, but when I click it open, it is empty.

So I added this code:

private void radGridView1_EditorRequired(object sender, EditorRequiredEventArgs e)
        {
            RadComboBoxEditor comboEditor = e.Editor as RadComboBoxEditor;
            string t = e.EditorType.ToString();


            if (comboEditor != null)
            {
                comboEditor.Items.Clear();

                for (int i = 0; i < (int)this.radGridView1.CurrentRow.Cells[2].Value; i++)
                {
                    comboEditor.Items.Add(new RadComboBoxItem(String.Format("item{0}", i + 1)));
                }

                comboEditor.SelectedIndex = 0;
            }

        }

The problem is that the e.Editor type is a textbox and not a combobox. It's like the textbox is on top of the combobox...

[Geert]

I'm still having the problem. the strangest thing is when I right click on the combobox. The list is being opened. So that works fine. But when I use the left click. The focus goed to the textbox at the back of the combobox.

When I type I can see that the focus is on the textbox. Is there a way to solve this?

I've allready tried 

 

e.CellElement.CanFocus =

false;

but with no success...

 

[Martin Vasilev]

Hi Geert,

Thank you for contacting me again.

After a couple of tests I have to admit that there is not an easy way to create different cells for one column. The main difficulty comes from the fact that you have to implement a custom editor, and change it  depending on the cell type. The standard editor for GridViewDataColumn is a text editor, and the EditorRequired event does not work there. Unfortunately, implementing custom editor is a very hard task and I cannot recommend it. We will consider adding such of functionality in some of the future releases.

Write me back if you have other questions.
 

Kind regards,
Martin Vasilev
the Telerik team

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[Dipak]

Did you addressed this issue in  version 2009.2 701 ?

[Martin Vasilev]

Hi Dipak,

Thank you for the question. Actually, with the new version Q2 2009, I have managed to implement different type of cell elements in one column. I have prepared a simple scenario that changes grid's cells to ComboBoxes for every even row in a custom GridViewTextBoxColumn. Please, find the example project as attachment to this message.

Write me back if you have any other questions.

All the best,
Martin Vasilev
the Telerik team

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[Dipak]

Thanks Martin.

This code is very usefull for me. I am looking for the sample and help I could not find anything related to date mask in the grid. Could you please update this example so that user can enter the formated Date (MM/dd/yy) in the masked edit kind of editor along with the lookup and plain text.

Thanks
Dipak

[Martin Vasilev]

Hello Dipak,

Thank you for getting back to me. It occurred to me a way to implement a similar scenario. Since in the latest version changing the editor for chosen cell become very easy, you can just change it to RadDateTimePickerEditor for the selected cells. You also could make a custom editor that matches exactly your needs. Please, consider the following code:
 

void radGridView1_EditorRequired(object sender, EditorRequiredEventArgs e)
{
    if (this.radGridView1.Columns[2].IsCurrent && (int)this.radGridView1.CurrentRow.Cells[0].Value % 2 == 0)
    {
        e.EditorType = typeof(RadDateTimeEditor);
    }
}

Write me back if you need additional assistance.

Regards,
Martin Vasilev
the Telerik team

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[Dipak]

Hi

Thanks this works fine for me. Now I can edit DateValue in DateTimeEditor. I have one formating problem. I am showing the Date in the grid in MM/dd/yyyy format. Once I edit this date and close the editor it will update the Date along with the time. I dont want the time portion here.Same thing happens when I am adding new date in this it is also showing Date and Time.

Could you please help me to format when it transfers from editor to grid cell ?
Thanks
Dipak

[Martin Vasilev]

Hello Dipak,

Thank you for writing again. RadGridView does not support different formatting for the cells in one and the same column. Nevertheless, you can work-around this by changing cell element text in the CellFormattingEvent. Please, consider the following code:
 

void radGridView1_CellFormatting(object sender, CellFormattingEventArgs e)
{
    if (e.CellElement.RowInfo is GridViewDataRowInfo && e.CellElement.ColumnIndex == 2)
    {
        DateTime date;
        if (DateTime.TryParse(e.CellElement.RowInfo.Cells[2].Value.ToString(), out date))
        {
            e.CellElement.Text = date.ToString("d MMMM yyyy");
        }
    }
}

Best wishes,
Martin Vasilev
the Telerik team

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[Peter Bogoyavlensky]

I have similiar problem - in one column I want have ComboBox cells and DateTime cells (depending on some conditions - actually it must be choosed by combobox value in other column).

As I understand - it can be done by catching CellFormatting event and proceed by e.CellElement.Children collection, add here a RadComboBoxElement or RadDateTimeEditorElement (is it?).

Questions:
1. What kind of base column type must I set?
2. Must I previously remove element from e.CellElement.Children collection (in order change cell type from combobox to datetime, for example)?
3. How often CellFormatting event is firing? Can I be sure that changing combobox value in other "ruler" column will start this event?

I  am not very familiar with C#, would it be possible obtain some examples in VB.Net?

I use Telerik RadControls for WinForms v2009.2.729.

[Martin Vasilev]

Hello Peter Bogoyavlensky,

Thank you for writing.

You are right, you can dynamically change the cell elements in CellFormatting event through CellElement.Children collection.

1. You can use any column type depending on your scenario. For instance, when I tested it, I used GridViewTextBoxColumn.

2. Since you want to swap elements between the ComboBox and the DateTimePicker, you have to clear the Children collection before adding the appropriate element.

3. CellFormatting event fires on every state change e.g. scrolling, filtering, sorting, etc. In most cases, it is enough to handle every situation including the described.

Please, consider the following code-block as an example for a similar scenario:

Private Sub radGridView1_CellBeginEdit(ByVal sender As Object, ByVal e As GridViewCellCancelEventArgs)
   If e.ColumnIndex = 2 Then
       e.Cancel = True
   End If
End Sub

Private Sub radGridView1_CellFormatting(ByVal sender As Object, ByVal e As CellFormattingEventArgs)
   If TypeOf e.CellElement.RowInfo Is GridViewDataRowInfo Then
       Dim conditionValue As Object = e.CellElement.RowInfo.Cells("id").Value
       Dim currentValue As Object = DirectCast(e.CellElement, GridDataCellElement).Value
       If e.CellElement.ColumnIndex = 2 Then
           If CInt(conditionValue) Mod 4 = 0 Then
               Dim datePicker As RadDateTimeEditorElement = Nothing
               If e.CellElement.Children.Count = 0 OrElse Not (TypeOf e.CellElement.Children(0) Is RadDateTimeEditorElement) Then
                   e.CellElement.Children.Clear()
                   datePicker = New RadDateTimeEditorElement()
                   AddHandler datePicker.ValueChanged, AddressOf datePicker_ValueChanged
                   e.CellElement.Children.Add(datePicker)
               ElseIf TypeOf e.CellElement.Children(0) Is RadDateTimeEditorElement Then
                   datePicker = DirectCast(e.CellElement.Children(0), RadDateTimeEditorElement)
               End If
               Dim d As DateTime
               If datePicker IsNot Nothing AndAlso currentValue IsNot Nothing AndAlso DateTime.TryParse(currentValue.ToString(), d) Then
                   Me.settingValue = True
                   datePicker.Value = Convert.ToDateTime(currentValue)
                   Me.settingValue = False
               End If
           Else
               Dim combo As RadComboBoxElement = Nothing
               If e.CellElement.Children.Count = 0 OrElse Not (TypeOf e.CellElement.Children(0) Is RadComboBoxElement) Then
                   e.CellElement.Children.Clear()
                   combo = New RadComboBoxElement()
                   combo.ForeColor = Color.Black
                   AddHandler combo.SelectedIndexChanged, AddressOf combo_SelectedIndexChanged
                   For i As Integer = 0 To 4
                       combo.Items.Add(New RadComboBoxItem([String].Format("Value{0}", i + 1)))
                   Next
                   e.CellElement.Children.Add(combo)
               ElseIf TypeOf e.CellElement.Children(0) Is RadComboBoxElement Then
                   combo = DirectCast(e.CellElement.Children(0), RadComboBoxElement)
               End If

               If combo IsNot Nothing Then
                   Me.settingValue = True
                   If currentValue IsNot Nothing AndAlso currentValue <> DBNull.Value Then
                       combo.SelectedIndex = Convert.ToInt32(currentValue)
                   Else
                       combo.SelectedIndex = -1
                   End If
                   Me.settingValue = False
               End If
           End If
       ElseIf e.CellElement.Children.Count > 0 AndAlso TypeOf e.CellElement.Children(0) Is RadComboBoxElement Then
           e.CellElement.Children.Clear()
       End If
   End If
End Sub

Private Sub datePicker_ValueChanged(ByVal sender As Object, ByVal e As EventArgs)
   If Not Me.settingValue AndAlso Me.radGridView1.CurrentCell IsNot Nothing Then
       Dim datePicker As RadDateTimeEditorElement = DirectCast(sender, RadDateTimeEditorElement)
       Me.radGridView1.CurrentCell.Value = datePicker.Value
   End If
End Sub

Private Sub combo_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
   If Not Me.settingValue AndAlso Me.radGridView1.CurrentCell IsNot Nothing Then
       Dim combo As RadComboBoxElement = DirectCast(sender, RadComboBoxElement)
       Me.radGridView1.CurrentCell.Value = combo.SelectedIndex
   End If
End Sub

Do not hesitate to contact me again if you have any other questions.

Greetings,
Martin Vasilev
the Telerik team

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[mtaber]

Can you explain in a bit more detail specifically what's going on in the CellBeginEdit event? I think I understand it, but maybe not.

Are you canceling going into edit mode for that column and in those rows because you have replaced the textbox with a control that is different than other types of edit controls in normally appear in that column? The code sample wasn't commented and I have a similar situation where I'm replacing the textbox with a combobox that is different in the last column and based on the information entered in the previous column. Thanks for any insight!

[Martin Vasilev]

Hi mtaber,

Thank you for the question.

I have canceled the BeginEdit event because I have substituted cell elements with my own elements (RadDateTimeEditorElement or RadComboBoxElement). In this way, I do not need to enter in edit mode and initialize the default column editor, because it is going to mess up with the new elements. I just use the elements' events to manage the change of the value and to save the cell value.

I hope this makes the things clearer. Write me back if you need additonal assistance.

Kind regards,
Martin Vasilev
the Telerik team

Instantly find answers to your questions on the new Telerik Support Portal.
Watch a video on how to optimize your support resource searches and check out more tips on the blogs.

[shortie]

Hello Support,

We need to have one column to show different editor type when editing according the values in other cells.

1. if the values in other cells match condition A, the editor type should be combobox when editing.

2. otherwise the editor type should be a datetimepicker.

Could you give a more elaborate sample in doing this?

BR/shortie

[Martin Vasilev]

Hi ChunChang,

Thank you for the question. You can use EditorRequierd event to change the cell editor based on a condition. Please, refer to our documentation for a detailed description on how to do that. Let me know if you have any additional questions.

Greetings,
Martin Vasilev
the Telerik team

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[Peter Bogoyavlensky]

I used version 2010.1.10.308 before and made some example:

There is grid with two column (type of GridViewComboBoxColumn). First column has DataSource like "Combo1", "Combo2" and "Date". First and second values must populate second cell with different Datasource, and third value must populate second cell with DateTime value.

Here is example code (I presume that it's not so smart code, sorry for that):

Public Class RadForm1
    Dim Condit As System.Collections.ArrayList
    Dim CbValue1 As System.Collections.ArrayList
    Dim CbValue2 As System.Collections.ArrayList

    Private Sub RadForm1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Condit = New System.Collections.ArrayList
        Condit.Add("Combo1")
        Condit.Add("Combo2")
        Condit.Add("Date")
        CbValue1 = New System.Collections.ArrayList
        CbValue1.Add("C1_1")
        CbValue1.Add("C1_2")
        CbValue2 = New System.Collections.ArrayList
        CbValue2.Add("C2_1")
        CbValue2.Add("C2_2")

        Dim column As Telerik.WinControls.UI.GridViewComboBoxColumn
        column = gridLogic.Columns(0)
        column.DataType = GetType(String)
        column.DataSource = Condit

        column = gridLogic.Columns(1)
        column.DataType = GetType(String)
        column.DataSource = CbValue1

        gridLogic.Rows.AddNew()
        gridLogic.Rows(0).Cells(0).Value = "Combo1"
        gridLogic.Rows(0).Cells(1).Value = "C1_1"

        gridLogic.Rows.AddNew()
        gridLogic.Rows(1).Cells(0).Value = "Combo1"
        gridLogic.Rows(1).Cells(1).Value = "C1_2"

        gridLogic.Rows.AddNew()
        gridLogic.Rows(2).Cells(0).Value = "Combo1"
        gridLogic.Rows(2).Cells(1).Value = "C1_1"
    End Sub


    Private Sub gridLogic_CellBeginEdit(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.GridViewCellCancelEventArgs) Handles gridLogic.CellBeginEdit
        Dim NumRow As Integer = gridLogic.Rows.IndexOf(gridLogic.CurrentRow)
        If gridLogic.Columns(1).IsCurrent AndAlso gridLogic.Rows(NumRow).Cells(0).Value = "Date" Then
            If gridLogic.Rows(NumRow).Cells(1).CellElement.Children.Count = 0 Then
                Dim dtel As New Telerik.WinControls.UI.RadDateTimeEditorElement
                AddHandler dtel.ValueChanged, AddressOf gridlogic_DateTime_ValueChanged
                dtel.Tag = NumRow
                dtel.Value = Now
                gridLogic.Rows(NumRow).Cells(1).CellElement.Children.Add(dtel)
                e.Cancel = True
            Else
                e.Cancel = True
            End If
        End If

        If gridLogic.Columns(0).IsCurrent Then
            Dim editor As Telerik.WinControls.UI.IInputEditor = Me.gridLogic.ActiveEditor
            If TypeOf (editor) Is Telerik.WinControls.UI.RadDropDownListEditor Then
                Dim comboElement As Telerik.WinControls.UI.RadDropDownListEditorElement = CType(CType(editor, Telerik.WinControls.UI.RadDropDownListEditor).EditorElement, Telerik.WinControls.UI.RadDropDownListEditorElement)
                AddHandler (comboElement.SelectedIndexChanged), AddressOf gridlogic_Condition_SelectedIndexChanged
            End If
        End If
    End Sub

    Private Sub gridlogic_Condition_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As EventArgs)
        Dim NumRow As Integer = gridLogic.Rows.IndexOf(gridLogic.CurrentRow)
        Dim NumCol As Integer = gridLogic.Columns.IndexOf(gridLogic.CurrentColumn)

        If CType(sender, Telerik.WinControls.UI.RadDropDownListEditorElement).SelectedIndex < 0 Then Exit Sub
        Dim item As String = CType(sender, Telerik.WinControls.UI.RadDropDownListEditorElement).SelectedItem.Value

        If item = "Combo1" Then
            If gridLogic.Rows(NumRow).Cells(1).CellElement.Children.Count > 0 Then
                If Not TypeOf gridLogic.Rows(NumRow).Cells(1).CellElement.Children(0) Is Telerik.WinControls.UI.RadDropDownListEditorElement Then
                    gridLogic.Rows(NumRow).Cells(1).CellElement.Children.Remove(gridLogic.Rows(NumRow).Cells(1).CellElement.Children(0))
                End If
            End If
            gridLogic.Rows(NumRow).Cells(1).Value = "C1_1"
        End If

        If item = "Combo2" Then
            If gridLogic.Rows(NumRow).Cells(1).CellElement.Children.Count > 0 Then
                If Not TypeOf gridLogic.Rows(NumRow).Cells(1).CellElement.Children(0) Is Telerik.WinControls.UI.RadDropDownListEditorElement Then
                    gridLogic.Rows(NumRow).Cells(1).CellElement.Children.Remove(gridLogic.Rows(NumRow).Cells(1).CellElement.Children(0))
                End If
            End If
            gridLogic.Rows(NumRow).Cells(1).Value = "C2_1"
        End If

        If item = "Date" Then
            If gridLogic.Rows(NumRow).Cells(1).CellElement.Children.Count = 0 Then
                Dim dtel As New Telerik.WinControls.UI.RadDateTimeEditorElement
                AddHandler dtel.ValueChanged, AddressOf gridlogic_DateTime_ValueChanged
                dtel.Tag = NumRow
                Try
                    dtel.Value = Now
                Catch ex As Exception
                End Try
                gridLogic.Rows(NumRow).Cells(1).CellElement.Children.Add(dtel)
            End If
        End If
    End Sub

    Private Sub gridlogic_DateTime_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
        Dim dt As Telerik.WinControls.UI.RadDateTimeEditorElement = CType(sender, Telerik.WinControls.UI.RadDateTimeEditorElement)
        gridLogic.Rows(dt.Tag).Cells(1).Value = dt.Value
    End Sub

    Private Sub gridLogic_CellEndEdit(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.GridViewCellEventArgs) Handles gridLogic.CellEndEdit
        If gridLogic.Columns(0).IsCurrent Then
            Dim editor As Telerik.WinControls.UI.IInputEditor = Me.gridLogic.ActiveEditor
            If TypeOf (editor) Is Telerik.WinControls.UI.RadDropDownListEditor Then
                Dim comboElement As Telerik.WinControls.UI.RadDropDownListEditorElement = CType(CType(editor, Telerik.WinControls.UI.RadDropDownListEditor).EditorElement, Telerik.WinControls.UI.RadDropDownListEditorElement)
                RemoveHandler (comboElement.SelectedIndexChanged), AddressOf gridlogic_Condition_SelectedIndexChanged
            End If
        End If
    End Sub

    Private Sub gridLogic_CellEditorInitialized(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.GridViewCellEventArgs) Handles gridLogic.CellEditorInitialized
        If gridLogic.Columns(1).IsCurrent Then
            If gridLogic.CurrentRow.Cells(0).Value = "Combo1" Or gridLogic.CurrentRow.Cells(0).Value = "Combo2" Then
                Dim NumRow As Integer = gridLogic.Rows.IndexOf(gridLogic.CurrentRow)
                Dim editor As Telerik.WinControls.UI.RadDropDownListEditor = gridLogic.ActiveEditor
                Dim editorElement As Telerik.WinControls.UI.RadDropDownListEditorElement = editor.EditorElement

                If gridLogic.CurrentRow.Cells(0).Value = "Combo1" Then
                    editorElement.DataSource = CbValue1
                    editorElement.SelectedText = "C1_1"
                End If
                If gridLogic.CurrentRow.Cells(0).Value = "Combo2" Then
                    editorElement.DataSource = CbValue2
                    editorElement.SelectedText = "C2_1"
                End If
            End If
        End If
    End Sub

End Class

It works fine but I upgrade to latest version 2011.3.11.1219.

I've changed RadComboBoxEditor to RadDropDownListEditor, and RadComboBoxEditorElement to RadDropDownListEditorElement. But I can not obtain CellElement from specific cell to change editor (from DropDownList to DateTimeEditor, or remove DateTimeEditor).

How can I change code? Is here some simplier way to obtain result (described above)?

[Svett]

Hello Peter,

It is not recommend to use the cell element outside the CellFormatting event because of the UI virtualization of RadGridView. I recommend using the EditorRequired event where you can replace the default editor with the one that you want. I am enclosing a sample project which demonstrates how you can do it.

Greetings,
Svett
the Telerik team

[Peter Bogoyavlensky]

Sure, catching EditorRequired event is helpful to change curent editor to desired (I mean, in accordance with first column value).
But this event fires only if I click on that cell - here I can change editor, populate Datasource property for combobox, set cell's value, etc.

But how can I change this editor before clicking on that cell? I mean, I change value in first column from "Combo" to "Date" and want to reflect that change immediatelly - value in second column must be set to appropriate (some date, probably stored in my value's array). Otherwise, if I change value in first column from "Date" to "Combo" - value in second column must be set to appropriate (some value from list in accordance with Datasource array linked with that combobox).

If I change value in second column's cell by catching CellValueChanged event from first column's cell - it can produce error because type of second column's cell would not be affordable for that new value.

I presume that I miss something.

[Svett]

Hello Peter,

First of all, if you are changing the editor dynamically, the underlying data source of the RadGridView should support the data types for all editors of the column that may appear. That means, if you have spin editor and date time picker, the underline field should be of the type that can host both values. I recommend using an object type for the field where you have dynamic editors.

By following your illustration, I concluded that you have two active editors which is impossible. I am not able to assist you efficiently by following the given information. Could you please open a support ticket where you can enclose a project which demonstrates your approach? In addition, give us the exact steps that we should follow to reproduce the error that you have experienced. This will allow us to assist you further.

Greetings,
Svett
the Telerik team

[Erin Arroyo]

Hi,
I have a grid that I have bound my columns to a datareader.  I have 2 columns that I look at in this grid when wanting to make a custom combobox for a cell and they are "Batch Status" and "Status ID" and they are both textbox cell types.  For the column "Batch Status" I want to make it a combobox for certain cells if the "Batch Status" is "Open".

To start out I create a list array of all my combobox items.
Private mstrBatchStatusList As New List(Of ComboBoxDataSourceObject)()

Then I go ahead and use CellFormatting to make the cell a combobox if the Batch Status is "Open".
Private Sub rgvBatch_CellBeginEdit(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.GridViewCellCancelEventArgs) Handles rgvBatch.CellBeginEdit
        '
        ' Got this from a website.  http://www.telerik.com/forums/dynamically-adding-controls-in-the-columns-in-the-grid
        ' The status column is a canceled Edit because I have substituted cell elements with my own elements
        ' (RadDropDownListEditorElement). In this way, I do not need to enter in edit mode and initialize the
        ' default column editor, because it is going to mess up with the new elements. I just use the elements'
        ' events to manage the change of the value and to save the cell value.
        '
        If e.Column.HeaderText = "Status" Then
            e.Cancel = True
        End If
    End Sub
    Private Sub rgvBatch_CellFormatting(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.CellFormattingEventArgs) Handles rgvBatch.CellFormatting
        '
        ' Edit
        '
        If e.CellElement.ColumnInfo.HeaderText = "Edit" Then
            'This is how we get the RadButtonElement instance from the cell
            Dim button As RadButtonElement = CType(e.CellElement.Children(0), RadButtonElement)
            If e.CellElement.RowInfo.Cells("Batch_Status").Value IsNot Nothing Then
                Dim title As String = e.CellElement.RowInfo.Cells("Batch_Status").Value.ToString()
                If title = "Deleted" Then
                    button.Enabled = False
                Else
                    button.Enabled = True
                End If
            End If
        End If
        '
        ' Delete
        '
        If e.CellElement.ColumnInfo.HeaderText = "Delete" Then
            'This is how we get the RadButtonElement instance from the cell
            Dim button As RadButtonElement = CType(e.CellElement.Children(0), RadButtonElement)
            If e.CellElement.RowInfo.Cells("Batch_Status").Value IsNot Nothing Then
                Dim title As String = e.CellElement.RowInfo.Cells("Batch_Status").Value.ToString()
                If title <> "Open" Or mblnReadOnly Then
                    button.Enabled = False
                Else
                    button.Enabled = True
                End If
            End If
        End If
        '
        ' Status
        '
        If TypeOf e.CellElement.RowInfo Is GridViewDataRowInfo Then
            If e.CellElement.ColumnInfo.HeaderText = "Status" Then
                If e.CellElement.RowInfo.Cells("Batch_Status").Value IsNot Nothing Then
                    Dim strBatchStatus As String = e.CellElement.RowInfo.Cells("Batch_Status").Value.ToString()
                    Dim currentStatusID As Object = e.CellElement.RowInfo.Cells("AccPac_Batch_Status_ID").Value.ToString()
                    If strBatchStatus = "Open" And Not mblnReadOnly Then
                        Dim gvDropDownList As RadDropDownListEditorElement = Nothing
                        If e.CellElement.Children.Count = 0 OrElse Not (TypeOf e.CellElement.Children(0) Is RadDropDownListEditorElement) Then
                            e.CellElement.Children.Clear()
                            gvDropDownList = New RadDropDownListEditorElement()
                            For intI = 0 To mstrBatchStatusList.Count - 1
                                gvDropDownList.Items.Add(New RadListDataItem(mstrBatchStatusList.Item(intI).MyString, mstrBatchStatusList.Item(intI).Id))
                            Next
                            e.CellElement.Children.Add(gvDropDownList)
                            '
                            ' Preset the Drop down
                            '
                            If gvDropDownList IsNot Nothing Then
                                If currentStatusID IsNot Nothing Then
                                    gvDropDownList.SelectedValue = Convert.ToInt32(currentStatusID)
                                Else
                                    gvDropDownList.SelectedIndex = -1
                                End If
                            End If
                        Else
                            gvDropDownList = DirectCast(e.CellElement.Children(0), RadDropDownListEditorElement)
                        End If
                    ElseIf e.CellElement.Children.Count > 0 AndAlso TypeOf e.CellElement.Children(0) Is RadDropDownListEditorElement Then
                        '
                        ' Make sure any cells in the status column that are not "Open" status do not get changed to a combobox
                        '
                        e.CellElement.Children.Clear()
                    End If
                End If
            ElseIf e.CellElement.Children.Count > 0 AndAlso TypeOf e.CellElement.Children(0) Is RadDropDownListEditorElement Then
                '
                ' Make sure any other columns do not get changed to a combobox
                '
                e.CellElement.Children.Clear()
            End If
        End If
    End Sub

The above code works perfectly to setting the cell to a combobox when the Batch Status is "Open" and the drop down contains the correct values that are in my list array of (mstrBatchStatusList.Item).

Here are my questions:
1.  When I want to change my combobox value to a different item in the combobox, first I need to scroll to the right since my column you can't see.  I then change my value and scroll back to the left.  I then scroll back to the right and my combobox becomes reset to the original value.  It looks like upon scrolling right it calls the CellFormating function and when it gets to this line of the code (If e.CellElement.Children.Count = 0 OrElse Not (TypeOf e.CellElement.Children(0) Is RadDropDownListEditorElement) Then) it doesn't recognize that it's currently a combobox so it resets the combo box back to the original status id.

Why does this happen and how do I get this to not happen?

2.  If there an event that can be used that triggers a combo box change event so I can check the value it's changing to and set a flag that a value changed in the grid?

Thanks

[Dimitar]

Hi,

As far as I can see your goal is to have a DropDownEditor on the place of the TextEditor. If that is the case, then you need to use a custom editor, instead of adding and removing children in the CellFormating event. We have an article which can of help for this purpose - Using custom editors.

Also the article Events can be found useful.

I hope this will be useful.

Regards,
Dimitar
Telerik

 

 

[Erin Arroyo]

Hi,
Thanks for your response and the custom editor worked much better than using the Cell Formatting but in the end I decided to go a different route.
I created the column from the beginning a GridViewComboBoxColumns.  Then at runtime I dynamically set the data source, value member, display member, and field name.  I then do a check and see if my status is "Open" I leave the combobox enabled else I disable the combo box so it only displays the text of my status.
Thanks again

[Dimitar]

Hi Erin,

Thank you for writing back.

I am glad that you have found a solution for your case. Do not hesitate to contact us if you have other questions.

 

Regards,
Dimitar
Telerik

 

 

[Rawad]

Dear

I'm trying to add a Combobox inside the DataGrid but for certain  rows and columns.
I'm using the event  CellFormatting, but how can I bind the "RadDropDownListElement".
I need to Fill it with data


Here is my code:


    Private Sub RadButton1_Click(sender As System.Object, e As System.EventArgs) Handles RadButton1.Click    
           Dim rowindex = RadGridView1.Rows.AddNew()
            rowindex.Cells(0).Value = 12
            rowindex.Cells(1).Value = "Name"
            rowindex.Cells(2).Value = TODAY

            rowindex = RadGridView1.Rows.AddNew()
            rowindex.Cells(0).Value = 999
            rowindex.Cells(1).Value = "Name"
            rowindex.Cells(2).Value = TODAY
    End Sub


    Private Sub RadGridView1_CellFormatting(sender As System.Object, e As Telerik.WinControls.UI.CellFormattingEventArgs) Handles RadGridView1.CellFormatting
        If e.CellElement.RowIndex <> -1 Then
            If e.CellElement.ColumnIndex = 0 Then
                If RadGridView1.Rows(e.CellElement.RowIndex).Cells(e.CellElement.ColumnIndex).Value = "999" Then
                    e.CellElement.Children.Add(New RadDropDownListElement())
                End If
            End If
        End If
    End Sub

[Dimitar]

Hi Ravad,

Thank you for writing.

The CellFormatting event is not suitable for such operations since it is fired very often. This event should be used for styling the existing grid elements not for adding new ones.

To achieve the desired functionality you can use the editors' events. For example you can change the editor depending on the cell value in the EditorRequired event, then you can add a data source to this editor in the CellEditorInitialized event:

Private Sub radGridView1_CellEditorInitialized(sender As Object, e As GridViewCellEventArgs)
    If TypeOf e.ActiveEditor Is RadDropDownListEditor Then
        Dim editor As RadDropDownListEditor = TryCast(e.ActiveEditor, RadDropDownListEditor)
        Dim element As RadDropDownListEditorElement = TryCast(editor.EditorElement, RadDropDownListEditorElement)
        element.DataSource = GetTable1()

        element.DisplayMember = "Name"
        element.ValueMember = "ID"
    End If
End Sub

Private Sub radGridView1_EditorRequired(sender As Object, e As EditorRequiredEventArgs)
    Dim i As Integer = 0
    If Integer.TryParse(radGridView1.CurrentCell.Value.ToString(), i) AndAlso i = 999 Then
        e.EditorType = GetType(RadDropDownListEditor)
        Return
    End If
End Sub

Please let me know if there is something else I can help you with. 

 

Regards,
Dimitar
Telerik

 

 

[Denius]

Hello, 

i need help ...

try to show data from List<> but shows on that column this information System.Collections.Generic.List ' 1[ ]

 

how to resolve ?

 

[Denius]

Oh...sorry try to show on Telerik RadGridView.

[Dimitar]

Hello Goran,

Generally, such objects are displayed in a hierarchy grid. The easiest way to display the data is to let the grid  generate the hierarchy by setting AutoGenerateHierarchy property to true: Object Relational Hierarchy Mode.

I hope this will be useful. Let me know if you have additional questions.

Regards,
Dimitar
Telerik by Progress