DataContextProxy

using System.Windows;
using System.Windows.Data;
 
namespace Utilities
{
    /// <summary>
    /// Allows binding to a viewmodel from within a data/contenttemplate that is bound to something else.
    ///
    /// Example:
    ///     <UserControl.Resources>
    ///         <DataContextProxy x:Key="dataContextProxy" />
    ///     </UserControl.Resources>    
    ///     ...
    ///     <DataTemplate>
    ///         <Button Content="Delete"
    ///                 Command="{Binding Source={StaticResource dataContextProxy}, Path=DataSource.DeleteClass}" 
    ///                 CommandParameter="{Binding}" />
    ///     </DataTemplate>
    ///
    /// </summary>
    public class DataContextProxy : FrameworkElement
    {
        public DataContextProxy()
        {
            this.Loaded += OnLoaded;
        }
        public string BindingPropertyName { get; set; }
        public BindingMode BindingMode { get; set; }
        public static readonly DependencyProperty DataSourceProperty = DependencyProperty.Register("DataSource", typeof(object), typeof(DataContextProxy), null);
        public object DataSource
        {
            get { return GetValue(DataSourceProperty); }
            set { SetValue(DataSourceProperty, value); }
        }
        private void OnLoaded(object sender, RoutedEventArgs e)
        {
            var binding = new Binding();
            if (!string.IsNullOrEmpty(BindingPropertyName))
            {
                binding.Path = new PropertyPath(BindingPropertyName);
            }
            binding.Source = DataContext;
            binding.Mode = BindingMode;
            SetBinding(DataSourceProperty, binding);
            // this.Loaded -= this.OnLoaded;
        }
    }
}