Using DropInfo.VisualTarget for the target of drop hint adorner to support IDropInfoBuilder

Author: bsundsbo

src/GongSolutions.WPF.DragDrop/DragDrop.cs

@@ -735,7 +735,7 @@ private static void OnRealTargetDragLeave(object sender, DragEventArgs e)
                 dropHandler.DragLeave(dropInfo);
                 if(_dragInProgress)
                 {
-                    DropHintHelpers.OnDragLeave(sender, dropHandler, dragInfo);
+                    DropHintHelpers.OnDragLeave(dropHandler, dragInfo, dropInfo);
                 }
             }
 
@@ -782,7 +782,7 @@ private static void DropTargetOnDragOver(object sender, DragEventArgs e, EventTy
             }
 
             dropHandler.DragOver(dropInfo);
-            DropHintHelpers.DragOver(sender, dropInfo);
+            DropHintHelpers.DragOver(dropInfo);
 
             if (dragInfo is not null)
             {

src/GongSolutions.WPF.DragDrop/DropHintHelpers.cs

@@ -76,10 +76,10 @@ public static void OnDropFinished()
         /// </summary>
         /// <param name="dropHandler">The <see cref="IDropTarget"/> for the operation</param>
         /// <param name="dragInfo">The <see cref="IDragInfo"/> initiating the drag</param>
-        /// <param name="sender">The target element of the drag</param>
-        public static void OnDragLeave(object sender, IDropTarget dropHandler, IDragInfo dragInfo)
+        /// <param name="dropInfo">Drop info containing with target.</param>
+        public static void OnDragLeave(IDropTarget dropHandler, IDragInfo dragInfo, IDropInfo dropInfo)
         {
-            var wrapper = _dropTargetHintReferences.Find(m => m.Target == sender);
+            var wrapper = _dropTargetHintReferences.Find(m => m.Target == dropInfo.VisualTarget);
             if (wrapper != null)
             {
                 var dropHintInfo = new DropHintInfo(dragInfo);
@@ -92,10 +92,9 @@ public static void OnDragLeave(object sender, IDropTarget dropHandler, IDragInfo
         /// Update drop hint for the current element.
         /// </summary>
         /// <param name="dropInfo"></param>
-        /// <param name="sender"></param>
-        public static void DragOver(object sender, IDropInfo dropInfo)
+        public static void DragOver(IDropInfo dropInfo)
         {
-            var wrapper = _dropTargetHintReferences.Find(m => m.Target == sender);
+            var wrapper = _dropTargetHintReferences.Find(m => m.Target == dropInfo.VisualTarget);
             if (wrapper != null)
             {
                 UpdateHintAdorner(wrapper, dropInfo.DropTargetHintAdorner, new DropHintData(dropInfo.DropTargetHintState, dropInfo.DropHintText));