GridViewBoundColumnBase AutoCompleteBoxColumn handling events, howto

[Jim]

I am trying to implement a autocompletebox in a grid column using GridViewBoundColumnBase

I don't know how to handle events, I assume it's something like the ???? below

 

 

 

Public Class AutoCompleteBoxColumn
    Inherits GridViewBoundColumnBase

    Public Overloads Overrides Function CreateCellEditElement(ByVal cell As GridViewCell, ByVal dataItem As Object) As FrameworkElement

        Me.BindingTarget = AutoCompleteBox.SelectedItemProperty

        Dim cellEditElement As AutoCompleteBox = New AutoCompleteBox()

        cellEditElement.SetBinding(AutoCompleteBox.SelectedItemProperty, CreateValueBinding())
        ??????cellEditElement.AddHandler(  gridAutoCompleteBox_Populating )
        Return (TryCast(cellEditElement, FrameworkElement))
    End Function
    Private Function CreateValueBinding() As System.Windows.Data.Binding
        Dim valueBinding As New System.Windows.Data.Binding()
        valueBinding.Mode = BindingMode.TwoWay
        valueBinding.NotifyOnValidationError = True
        valueBinding.ValidatesOnExceptions = True
        valueBinding.UpdateSourceTrigger = UpdateSourceTrigger.Explicit
        valueBinding.Path = New PropertyPath(Me.DataMemberBinding.Path.Path)
        Return valueBinding
    End Function
End Class

Private Sub gridAutoCompleteBox_Populating(sender As System.Object, e As System.Windows.Controls.PopulatingEventArgs)

    'Access database here
    e.Cancel = True

End Sub

Any ideas
Thanks
Jim

[Maya]

Hello Jim,

I would recommend you to work directly with GridViewComboBoxColumn. Once you set its IsComboBoxEditable property to "True", the autocomplete functionality will be turned on by default.
Please take a look at our online documentation and demos for a reference.

Greetings,
Maya
the Telerik team

[Jim]

I need the functionality of the autocomplete box.
I can get it working OK as a stand alone control.
I originally tried <DataTemplate> which nearly worked.
And then GridViewBoundColumnBase which again nearly worked.
I have difficulty accessing the itemsource and setting handlers once it's in the Grid
Thanks
Jim

[Maya]

Hello Jim,

I am sending you a sample project illustrating how you can define an AutoComplteBox as a CellEditTemplate. You can add handlers directly to the element.
Will that work for you ? 

Best wishes,
Maya
the Telerik team

[Jim]

Thanks I look forward to reading this in the morning.
For now it's time for zzzz
Regards
Jim

[Jim]

Hello and thanks for the example , I am getting nearer.
1) I should have worked out how to capture events by just adding an attribute to the xaml. I was thrown by ...
Handles clause requires a WithEvents variable defined in the containing type or one of its base types.
2) I can get which AutoCompleteBox generating the populating event from the sender parameter, and thus set its Item.Source dynamically.

So my autocompletebox offers the drop down and the cell displays the selected value.
However when I move to a new row the data reverts to what was originally in the row.
I have tired below to no avail.
Jim

Private Sub gridAutoCompleteBox_SelectionChanged(sender As System.Object, e As System.Windows.Controls.SelectionChangedEventArgs)
      Dim selectedRoomType As Roomtype = DirectCast(e.AddedItems(0), Roomtype)
      Dim currentRowRoomType As Roomtype = DirectCast(RadGridView1.SelectedItem, Roomtype)
     RadGridView1.Items.EditItem(currentRowRoomType)
      currentRowRoomType = selectedRoomType
      RadGridView1.Items.CommitEdit()
      Dim x As Integer = 0
  End Sub

[Maya]

Hello Jim,

How do you define your column - do you create your own custom one or you used the approach with having a CellEditTemplate ? Do you set the DataMemberBinding of the column ? Will it be possible to update the project I attached previously so that it reflects your scenario and let me know how do you change it  ? 

 

Kind regards,
Maya
the Telerik team

[Jim]

Grid xaml is ..
<telerik:RadGridView AutoGenerateColumns="False" Grid.Row="1" HorizontalAlignment="Left" Name="RadGridView1" VerticalAlignment="Top" Grid.ColumnSpan="4" Height="282" Width="640" >

    <telerik:RadGridView.Columns>

        <telerik:GridViewDataColumn UniqueName="RoomTypeCode" DataMemberBinding="{Binding RoomTypeCode}" Header="Room Type Code">

            <telerik:GridViewDataColumn.CellEditTemplate>

                <DataTemplate>

                    <sdk:AutoCompleteBox  x:Name="jimsAutoCompleteBox" SelectionChanged ="gridAutoCompleteBox_SelectionChanged" Populating="gridAutoCompleteBox_Populating" VerticalAlignment="Top" ValueMemberPath="RoomTypeCode" Width="133" HorizontalAlignment="Left" Grid.ColumnSpan="2" MinimumPrefixLength="1" MinimumPopulateDelay="500">

                        <sdk:AutoCompleteBox.ItemTemplate>

                            <DataTemplate>

                                <StackPanel Orientation="Horizontal">

                                    <TextBlock Text="{Binding RoomTypeCode}" />

                                    <TextBlock Text=" : " />

                                    <TextBlock Text="{Binding Description}" />

                                </StackPanel>

                            </DataTemplate>

                        </sdk:AutoCompleteBox.ItemTemplate>

                    </sdk:AutoCompleteBox>

                </DataTemplate>

            </telerik:GridViewDataColumn.CellEditTemplate>

        </telerik:GridViewDataColumn>

        <telerik:GridViewDataColumn DataMemberBinding="{Binding Description, Mode=TwoWay}" Header="Room Description"  Background="#FFEBEBEB" IsReadOnly="True"/>

    </telerik:RadGridView.Columns>

</telerik:RadGridView>

[Jim]

Hmm
Tried your supplied example again.
And whilst the AutoCompleteBox and drop down seem to work, it appears that the data does not go in the grid when you exit the cell
Or am I doing something wromg ?
Jim

[Maya]

Hi Jim,

You are quite right. I missed to set just a single property in the CellEditTemplate definition. Please set the Mode property of Text Binding of AutoComplateBox:

<input:AutoCompleteBox Text="{Binding Name, Mode=TwoWay}"
                                                   ItemsSource="{Binding Players, Source={StaticResource MyViewModel}}" />

 

Best wishes,
Maya
the Telerik team