Using a Grid as an ItemsHost - wpf

Question

I would like to use a Grid as an ItemsHost but none of the items appear in their bound (column, row) positions. How can I make this work? As a simple example:
XAML
<ItemsControl ItemsSource="{Binding DataSet}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Grid.Column="{Binding Col}" Grid.Row="{Binding Row}" Text="{Binding Text}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
<ItemsControl.Style>
<Style TargetType="{x:Type ItemsControl}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ItemsControl}">
<Grid HorizontalAlignment="Stretch" IsItemsHost="True">
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ItemsControl.Style>
</ItemsControl>
Codebehind
Class Window1
Private myTestData As TestData
Public Sub New()
' This call is required by the Windows Form Designer.
InitializeComponent()
' Add any initialization after the InitializeComponent() call.
myTestData = New TestData()
Me.DataContext = myTestData
End Sub
End Class
Class TestData
Private myDataSet As List(Of DataPoint)
Public Property DataSet() As List(Of DataPoint)
Get
Return myDataSet
End Get
Set(ByVal value As List(Of DataPoint))
myDataSet = value
End Set
End Property
Public Sub New()
Me.DataSet = New List(Of DataPoint)
For x As Integer = 0 To 1
For y As Integer = 0 To 1
Me.DataSet.Add(New DataPoint(x, y, "Column " + x.ToString + ", Row " + y.ToString))
Next
Next
End Sub
End Class
Class DataPoint
Private myRow As Integer
Public Property Row() As Integer
Get
Return myRow
End Get
Set(ByVal value As Integer)
myRow = value
End Set
End Property
Private myCol As Integer
Public Property Col() As Integer
Get
Return myCol
End Get
Set(ByVal value As Integer)
myCol = value
End Set
End Property
Private myText As String
Public Property Text() As String
Get
Return myText
End Get
Set(ByVal value As String)
myText = value
End Set
End Property
Public Sub New(ByVal x As Integer, ByVal y As Integer, ByVal name As String)
Me.Row = y
Me.Col = x
Me.Text = name
End Sub
End Class

Answer 1

Because you're using an ItemsControl, a container is generated for each item. That container (an instance of ContentPresenter for a plain old ItemsControl) wraps the TextBlock, and is a direct child of the Grid. Therefore, the Grid never even sees the Column and Row properties on the TextBlock because it's looking instead at the container.
You can solve this by setting an ItemContainerStyle that binds the appropriate properties for the container:
<ItemsControl.ItemContainerStyle>
<Style TargetType="ContentPresenter">
<Setter Property="Grid.Column" Value="{Binding Column}"/>
<Setter Property="Grid.Row" Value="{Binding Row}"/>
</Style>
</ItemsControl.ItemContainerStyle>

Answer 2

Possible workaround: if you use UniformGrid, you may not need to specify the rows and columns.