Change DataGrid Column Headers in WPF

Question

I have a DataGrid as shown below

    <DataGrid x:Name="dataGrid" Margin="0,5,10,5" AutoGenerateColumns="False" ItemsSource="{Binding Products, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"  >
    <DataGrid.Columns>
      <DataGridTextColumn x:Name="productName" Binding="{Binding Path Name}" Header="Name To Change">
    </DataGrid.Columns>

For the code I'm using the DataContextSpy

    public class DataContextSpy : Freezable
{
    public DataContextSpy()
    {
        // This binding allows the spy to inherit a DataContext.
        BindingOperations.SetBinding(this, DataContextProperty, new Binding());
    }

    public object DataContext
    {
        get { return GetValue(DataContextProperty); }
        set { SetValue(DataContextProperty, value); }
    }

    // Borrow the DataContext dependency property from FrameworkElement.
    public static readonly DependencyProperty DataContextProperty = FrameworkElement
        .DataContextProperty.AddOwner(typeof(DataContextSpy));

    protected override Freezable CreateInstanceCore()
    {
        // We are required to override this abstract method.
        throw new NotImplementedException();
    }
}

Then I have the MVVM Viewmodel with the property which i want to bind the header to like this:

    public class ViewModel: ViewModelBase{
    string header1;
    Public string Header1{
    get{return header1;}
    set{
    Set(ref header1, value);
    }
    ...........
    My question is why is it not binding to the property? Anny suggestions?

Answer 1

If Header1 is defined in the same view model class as the Products property, you could use a HeaderTemplate like this:

<DataGridTextColumn x:Name="productName" Binding="{Binding Path=Name}">
    <DataGridTextColumn.HeaderTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding Path=DataContext.Header1, RelativeSource={RelativeSource AncestorType=DataGrid}}" />
        </DataTemplate>
    </DataGridTextColumn.HeaderTemplate>
</DataGridTextColumn>