GridViewComboBoxColumn and HierarchyChildTemplate

[david ocasio]

Not sure if this is a bug or not 
I suspect it is

I have a Radgrid in a HierarchyChildTemplate with a comboxcolumn

it order to get the Itemssource to the comboboxolumn for the lookup i have hooked the
loaded event of the grid and load the itemsource like so

            <telerikGridView:RadGridView.HierarchyChildTemplate>
                <DataTemplate>
                    <telerikGridView:RadGridView ItemsSource="{Binding lstTestClass}" AutoGenerateColumns="False" Loaded="SetUpChildComboBox">
                        <telerikGridView:RadGridView.Columns >
                            <telerikGridView:GridViewSelectColumn></telerikGridView:GridViewSelectColumn>
                            <telerikGridView:GridViewDataColumn DataMemberBinding="{Binding iQty,Mode=TwoWay}" />
                            <telerikGridView:GridViewComboBoxColumn UniqueName="ComboCol"  DisplayMemberPath="NameState" SelectedValueMemberPath="IDState" DataMemberBinding="{Binding IDState}" />
                        </telerikGridView:RadGridView.Columns>
                    </telerikGridView:RadGridView>
                </DataTemplate>
            </telerikGridView:RadGridView.HierarchyChildTemplate>

    Private Sub SetUpChildComboBox(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs)
        Dim RadGridview As RadGridView = DirectCast(sender, RadGridView)
        DirectCast(RadGridview.Columns("ComboCol"), GridViewComboBoxColumn).ItemsSource = collStates
    End Sub

Problem is the initial value of that column is not shown even though it is in the data.

If i click in the cell to edit
The value is already selected (from the combo box)  
and when leaving edit mode is now shown in the cell.

so the questions:

1. am i hooking the wrong event
2. is there another/better  way to do it
3. is it a bug

i have included screenshots of  the problem.

thanks
dco

below find the test project i made to highlight and test the issue.

<UserControl xmlns:telerikGridView="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.GridView"  x:Class="agTestBed.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480">
  <Grid x:Name="LayoutRoot">
        <telerikGridView:RadGridView x:Name="TestGrid" SelectionMode="Multiple" AutoGenerateColumns="False">
            <telerikGridView:RadGridView.HierarchyChildTemplate>
                <DataTemplate>
                    <telerikGridView:RadGridView ItemsSource="{Binding lstTestClass}" AutoGenerateColumns="False" Loaded="SetUpChildComboBox">
                        <telerikGridView:RadGridView.Columns >
                            <telerikGridView:GridViewSelectColumn></telerikGridView:GridViewSelectColumn>
                            <telerikGridView:GridViewDataColumn DataMemberBinding="{Binding iQty,Mode=TwoWay}" />
                            <telerikGridView:GridViewComboBoxColumn UniqueName="ComboCol"  DisplayMemberPath="NameState" SelectedValueMemberPath="IDState" DataMemberBinding="{Binding IDState}" />
                        </telerikGridView:RadGridView.Columns>
                    </telerikGridView:RadGridView>
                </DataTemplate>
            </telerikGridView:RadGridView.HierarchyChildTemplate>
            <telerikGridView:RadGridView.Columns>
                <telerikGridView:GridViewSelectColumn></telerikGridView:GridViewSelectColumn>
                <telerikGridView:GridViewDataColumn DataMemberBinding="{Binding iQty,Mode=TwoWay}" ></telerikGridView:GridViewDataColumn>
                <telerikGridView:GridViewComboBoxColumn UniqueName="ComboCol"  DisplayMemberPath="NameState" SelectedValueMemberPath="IDState" DataMemberBinding="{Binding IDState}" />
            </telerikGridView:RadGridView.Columns>
        </telerikGridView:RadGridView>
  </Grid>
</UserControl>

Imports System.Windows.Data
Imports System.Windows.Ria.Data
Imports Telerik.Windows.Controls
Imports Telerik.Windows.Data
Imports System.ComponentModel
Imports System.ComponentModel.DataAnnotations
Imports System.Collections.ObjectModel
Imports System.Runtime.CompilerServices

Partial Public Class MainPage
    Inherits UserControl

    Public Sub New()
        InitializeComponent()
    End Sub

    Public CollTestclass As New ObservableCollection(Of TestClass)
    Public collStates As New ObservableCollection(Of State)

    Private Sub MainPage_Loaded(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs) Handles Me.Loaded

        'create states list data
        collStates.Add(New State With {.IDState = "0", .NameState = "FL"})
        collStates.Add(New State With {.IDState = "1", .NameState = "GA"})

        ' create test data
        CollTestclass.Add(New TestClass With {.iQty = 1, .IDState = "0", .lstTestClass = Makeitup()})
        CollTestclass.Add(New TestClass With {.iQty = 2, .IDState = "1", .lstTestClass = Makeitup()})
        CollTestclass.Add(New TestClass With {.iQty = 3, .IDState = "1", .lstTestClass = Makeitup()})
        CollTestclass.Add(New TestClass With {.iQty = 4, .IDState = "0", .lstTestClass = Makeitup()})
        CollTestclass.Add(New TestClass With {.iQty = 5, .IDState = "1", .lstTestClass = Makeitup()})
        CollTestclass.Add(New TestClass With {.iQty = 6, .IDState = "0", .lstTestClass = Makeitup()})
        CollTestclass.Add(New TestClass With {.iQty = 7, .IDState = "1", .lstTestClass = Makeitup()})

        ' set child table definition
        Dim detailDefinition As New GridViewTableDefinition()
        detailDefinition.Relation = New PropertyRelation("lstTestClass")
        TestGrid.TableDefinition.ChildTableDefinitions.Add(detailDefinition)

        ' set up main grid datasources
        DirectCast(TestGrid.Columns("ComboCol"), GridViewComboBoxColumn).ItemsSource = collStates
        TestGrid.ItemsSource = CollTestclass
    End Sub

    Public Function Makeitup() As ObservableCollection(Of TestClass)
        Dim CollTestclass As New ObservableCollection(Of TestClass)
        CollTestclass.Add(New TestClass With {.iQty = 1, .IDState = "0"})
        CollTestclass.Add(New TestClass With {.iQty = 2, .IDState = "1"})
        CollTestclass.Add(New TestClass With {.iQty = 3, .IDState = "1"})
        CollTestclass.Add(New TestClass With {.iQty = 4, .IDState = "0"})
        CollTestclass.Add(New TestClass With {.iQty = 5, .IDState = "1"})
        CollTestclass.Add(New TestClass With {.iQty = 6, .IDState = "0"})
        CollTestclass.Add(New TestClass With {.iQty = 7, .IDState = "1"})
        Return CollTestclass
    End Function

    Private Sub SetUpChildComboBox(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs)
        Dim RadGridview As RadGridView = DirectCast(sender, RadGridView)
        DirectCast(RadGridview.Columns("ComboCol"), GridViewComboBoxColumn).ItemsSource = collStates
    End Sub

    Private Sub TestGrid_DataLoaded(ByVal sender As Object, ByVal e As System.EventArgs) Handles TestGrid.DataLoaded
    End Sub

    Private Sub TestGrid_Loaded(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs) Handles TestGrid.Loaded
    End Sub
End Class

Public Class State
    <Display(Name:="IDState", Description:="IDState")> _
    Public Property IDState() As String
        Get
            Return _IDState
        End Get
        Set(ByVal value As String)
            _IDState = value
        End Set
    End Property
    Protected _IDState As String


    <Display(Name:="NameState", Description:="NameState")> _
    Public Property NameState() As String
        Get
            Return _NameState
        End Get
        Set(ByVal value As String)
            _NameState = value
        End Set
    End Property
    Protected _NameState As String

End Class

Public Class TestClass
    Implements INotifyPropertyChanged

    Public Event PropertyChanged(ByVal sender As Object, ByVal e As System.ComponentModel.PropertyChangedEventArgs) Implements System.ComponentModel.INotifyPropertyChanged.PropertyChanged
    Private Sub FirePropertyChanged(ByVal [property] As String)
        If Not String.IsNullOrEmpty([property]) Then
            RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs([property]))
        End If
    End Sub

    <Display(Name:="iQty", Description:="iQty")> _
    Public Property iQty() As Integer
        Get
            Return _iQty
        End Get
        Set(ByVal value As Integer)
            _iQty = value
            FirePropertyChanged("iQty")
        End Set
    End Property
    Protected _iQty As Integer


    <Display(Name:="IDState", Description:="IDState")> _
    Public Property IDState() As String
        Get
            Return _IDState
        End Get
        Set(ByVal value As String)
            _IDState = value
            FirePropertyChanged("IDState")
        End Set
    End Property
    Protected _IDState As String


    <Display(Name:="lstTestClass", Description:="lstTestClass")> _
    Public Property lstTestClass() As ObservableCollection(Of TestClass)
        Get
            Return _lstTestClass
        End Get
        Set(ByVal value As ObservableCollection(Of TestClass))
            _lstTestClass = value
            FirePropertyChanged("lstTestClass")
        End Set
    End Property
    Protected _lstTestClass As ObservableCollection(Of TestClass)

End Class

[Pavel Pavlov]

Hello david ocasio,
Thank you for sending such detailed illustration of the bug. It helped me to quickly isolate the problem.
I have updated your Telerik points. The bug will be fixed for the upcoming Q3 ServicePack release.

Meanwhile  I have found a workaround with your code.

To make the combo work - please use the DataLoaded instead of the Loaded event of the nested RadGridView when setting the ItemsSource of the  combo column.

Kind regards,
Pavel Pavlov
the Telerik team

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[David Ocasio]

Interestingly,

you are correct in my test project
changing it to the dataloaded event did work
(after i remembered to change the event signature to eventargs instead of routedeventargs)

but in my big project in did not work .
instead the id started showing up.
i am using your internal builds though so it may be that too

anyway bottom line
i changed the code to use templates instead
embedded a regular combo box
and that works fine

i will wait for the service pack you mentioned to change it back  to the combo column

thanks for your help
dco