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WPF Binding to DataRow Columns

Hi,

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

mikebirt

Hi,

You can use the dot operator to reference properties of a binding source, so for example you could use Parent.MyObject.IsExpanded - this is assuming MyObject is an instance of a class which has an IsExpanded property. Alternatively, you can easily implement a data provider to do things slightly more complex. You implement them in a class, then in xaml you create your instance:

<Window.Resources>

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AJS_Developer

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Thanks for your suggestions mikebirt.

I've attached 2 source files that are a very basic example of what I'm trying to do. 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?

Thanks for all your help!
Dave

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

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