From 05aa38279a6721289900416c27b71d7d0cb5f786 Mon Sep 17 00:00:00 2001
From: punker76 <punkerat76@gmail.com>
Date: Mon, 14 Oct 2013 23:22:15 +0200
Subject: [PATCH] add SourceIndex to DragInfo

---
 GongSolutions.Wpf.DragDrop/DragInfo.cs  | 9 +++++++++
 GongSolutions.Wpf.DragDrop/IDragInfo.cs | 5 +++++
 2 files changed, 14 insertions(+)

diff --git a/GongSolutions.Wpf.DragDrop/DragInfo.cs b/GongSolutions.Wpf.DragDrop/DragInfo.cs
index 94707653..fa5a653b 100644
--- a/GongSolutions.Wpf.DragDrop/DragInfo.cs
+++ b/GongSolutions.Wpf.DragDrop/DragInfo.cs
@@ -62,7 +62,10 @@ public DragInfo(object sender, MouseButtonEventArgs e)
 
           if (itemParent != null) {
             this.SourceCollection = itemParent.ItemsSource ?? itemParent.Items;
+            this.SourceIndex = itemParent.ItemContainerGenerator.IndexFromContainer(item);
             this.SourceItem = itemParent.ItemContainerGenerator.ItemFromContainer(item);
+          } else {
+            this.SourceIndex = -1;
           }
           this.SourceItems = itemsControl.GetSelectedItems();
 
@@ -132,6 +135,12 @@ public DragInfo(object sender, MouseButtonEventArgs e)
     /// </remarks>
     public IEnumerable SourceCollection { get; private set; }
 
+    /// <summary>
+    /// Gets the position from where the item was dragged.
+    /// </summary>
+    /// <value>The index of the source.</value>
+    public int SourceIndex { get; private set; }
+
     /// <summary>
     /// Gets the object that a dragged item is bound to.
     /// </summary>
diff --git a/GongSolutions.Wpf.DragDrop/IDragInfo.cs b/GongSolutions.Wpf.DragDrop/IDragInfo.cs
index 91f156e6..81111c76 100644
--- a/GongSolutions.Wpf.DragDrop/IDragInfo.cs
+++ b/GongSolutions.Wpf.DragDrop/IDragInfo.cs
@@ -49,6 +49,11 @@ public interface IDragInfo
     /// </remarks>
     IEnumerable SourceCollection { get; }
 
+    /// <summary>
+    /// Gets the position from where the item was dragged.
+    /// </summary>
+    int SourceIndex { get; }
+
     /// <summary>
     /// Gets the object that a dragged item is bound to.
     /// </summary>