DropDownListEditor ComboBox Mode

[Chris Gethin]

Is it possible to set a DropDownListEditor in a PropertyGrid to behave like a ComboBox?

I have tried setting the DropDownStyle property to RadDropDownStyle.DropDown, which looks as though this should setup this behaviour, but it does not seem to work. It is not possible to enter text even when this has been set.

Is there an additional step that needs to be taken in order for the dropdown list to allow text entry?

Thanks,

Chris

[Ivan Petrov]

Hi Chris,

Thank you for writing.

You can use the EditorInitialized event to change the drop down editor behavior. Here is a code snippet which demonstrates this:

private void radPropertyGrid1_EditorInitialized(object sender, PropertyGridItemEditorInitializedEventArgs e)
{
  if (e.Editor is PropertyGridDropDownListEditor)
  {
    PropertyGridDropDownListEditor editor = e.Editor as PropertyGridDropDownListEditor;
    BaseDropDownListEditorElement element = editor.EditorElement as BaseDropDownListEditorElement;
    element.DropDownStyle = RadDropDownStyle.DropDown;
  }
}

I hope this will be useful. Should you need further assistance, I would be glad to help.
 
Regards,
Ivan Petrov
the Telerik team

[Cesar]

How can I populate the dropdown list with items?

Please in VB.NET

[Dess | Tech Support Engineer, Principal]

Hello, Cesar,     
 
In the EditorInitialized event you have access to the BaseDropDownListEditorElement. You can either bind the drop down by setting the DataSource property or add items programmatically to the Items collection. The following help articles demonstrates the two approaches for populating the drop down with data:

https://docs.telerik.com/devtools/winforms/controls/dropdown-listcontrol-and-checkeddropdownlist/dropdownlist/populating-with-data/design-time
https://docs.telerik.com/devtools/winforms/controls/dropdown-listcontrol-and-checkeddropdownlist/dropdownlist/populating-with-data/adding-items-programmatically

I have prepared a sample code snippet for your reference: 

Sub New()

    InitializeComponent()

    Me.RadPropertyGrid1.SelectedObject = Me
    AddHandler Me.RadPropertyGrid1.EditorInitialized, AddressOf RadPropertyGrid_EditorInitialized
    AddHandler Me.RadPropertyGrid1.EditorRequired, AddressOf RadPropertyGrid1_EditorRequired
End Sub

Private Sub RadPropertyGrid_EditorInitialized(sender As Object, e As Telerik.WinControls.UI.PropertyGridItemEditorInitializedEventArgs)
    Dim editor As PropertyGridDropDownListEditor = TryCast(e.Editor, PropertyGridDropDownListEditor)
    If editor IsNot Nothing AndAlso e.Item.Label = "Text" Then
        Dim element As BaseDropDownListEditorElement = TryCast(editor.EditorElement, BaseDropDownListEditorElement)
        For index = 1 To 10
            element.Items.Add("Item"&index)
        Next
    End If
End Sub

Private Sub RadPropertyGrid1_EditorRequired(sender As Object, e As PropertyGridEditorRequiredEventArgs)
    If e.Item.Label ="Text" Then
        e.EditorType= GetType(PropertyGridDropDownListEditor)
    End If
End Sub

I hope this information helps. 

Regards,
Dess | Tech Support Engineer, Sr.
Progress Telerik

[Cesar]

Thank you. I took the code sample you sent as base code and it ran well.  Dropdownlisteditor shows all items I configured, but when I select one of them, it displays "nothing" as selected value.  How can I solve this issue?

[Dess | Tech Support Engineer, Principal]

 

Hello, Cesar,

The attached gif file illustrates the achieved behavior with the previously suggested solution. I suppose that you are referring to the situation that the selected value from the drop down list is not initialized the next time the editor is activated. To handle this case, you need to set the BaseDropDownListEditorElement.SelectedValue property to the value PropertyGridItem after adding the items in the BaseDropDownListEditorElement:

    Private Sub RadPropertyGrid_EditorInitialized(sender As Object, e As Telerik.WinControls.UI.PropertyGridItemEditorInitializedEventArgs)
        Dim editor As PropertyGridDropDownListEditor = TryCast(e.Editor, PropertyGridDropDownListEditor)
        If editor IsNot Nothing AndAlso e.Item.Label = "Text" Then
            Dim element As BaseDropDownListEditorElement = TryCast(editor.EditorElement, BaseDropDownListEditorElement)
            For index = 1 To 10
                element.Items.Add("Item"&index)
            Next
            Dim propertyItem As PropertyGridItem = TryCast(e.Item, PropertyGridItem)
            element.SelectedValue = propertyItem.Value
        End If

    End Sub

Should you have further questions please let me know.

 

Regards,
Dess | Tech Support Engineer, Sr.
Progress Telerik