WPF Binding to DataRow Columns - wpf

Question

I've taken some sample code from http://sweux.com/blogs/smoura/index.php/wpf/2009/06/15/wpf-toolkit-datagrid-part-iv-templatecolumns-and-row-grouping/ that provides grouping of data in a WPF DataGrid. I'm modifying the example to use a DataTable instead of a Collection of entities.
My problem is in translating a binding declaration {Binding Parent.IsExpanded}, which works fine where Parent is a reference to an entity that has the IsExpanded attribute, to something that will work for my weakly typed DataTable, where Parent is the name of a column and references another DataRow in the same DataTable. I've tried declarations like {Binding Parent.Items[IsExpanded]} and {Binding Parent("IsExpanded")} but none of these seem to work.
How can I create a binding to the IsExpanded column of the DataRow Parent in my DataTable?
Thanks in advance,
Dave
EDIT: I've created some sample code for a generic case of this problem:
Window1.xaml:
<Window x:Class="Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:WpfToolkit="http://schemas.microsoft.com/wpf/2008/toolkit"
Title="Window1" Height="300" Width="300">
<Grid>
<WpfToolkit:DataGrid
Name="dgSampleData"
ItemsSource="{Binding}"
AutoGenerateColumns="True"
Margin="0,75,0,0">
<WpfToolkit:DataGrid.Columns>
<WpfToolkit:DataGridTextColumn
Header="Bound Data"
Binding="{Binding Col3.Item(0)}"
/>
</WpfToolkit:DataGrid.Columns>
</WpfToolkit:DataGrid>
</Grid>
</Window>
Window1.xaml.vb:
Imports System.Data
Class Window1
Private Sub Window1_Loaded(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs) Handles Me.Loaded
Dim dtSampleData As New DataTable
dtSampleData.Columns.Add("Col1")
dtSampleData.Columns.Add("Col2")
dtSampleData.Columns.Add("Col3")
dtSampleData.Rows.Add(dtSampleData.NewRow())
dtSampleData.Rows.Add(dtSampleData.NewRow())
dtSampleData.Rows(0).Item(0) = "r1c1"
dtSampleData.Rows(0).Item(1) = "r1c2"
dtSampleData.Rows(0).Item(2) = dtSampleData.Rows(0)
dtSampleData.Rows(1).Item(0) = "r2c1"
dtSampleData.Rows(1).Item(1) = "r2c2"
dtSampleData.Rows(1).Item(2) = dtSampleData.Rows(0)
dgSampleData.DataContext = dtSampleData
End Sub
End Class
I've tried using the line Binding="{Binding Col3.Item(0)}" to show the value r1c1, but nothing appears in the cell contents. Why is that? Shouldn't Item(0) be just another property of Col3?

Answer 1

This binding expression will bind to a column named IsExpanded on a DataTable property named BindingDataTable on the object which is set as the views DataContext.
<CheckBox IsChecked="{Binding BindingDataTable.(Rows)[0][IsExpanded]}"
Content="Test"></CheckBox>
However I am specifying the first row ([0]) of the DataTable explicitly. I've not used the WPF DataGrid before so I'm not sure at this point how to get the current row index that is being bound...I'll see what I can work out and update if found.