ES-975464 - Resolve the ReadMe issue in this sample repository

Author: SreemonPremkumarM

README.md

@@ -1,2 +1,80 @@
-# How to drag and drop between two winui treeview?
-This example describes how to drag and drop between two winui treeview.
+# How to drag and drop between two WinUI TreeView
+
+This example describes how to drag and drop between two [WinUI TreeView](https://www.syncfusion.com/winui-controls/treeview) (SfTreeView).
+
+You can customize the dragging operation between two treeview by using the [SfTreeView.ItemDragStarting](https://help.syncfusion.com/cr/winui/Syncfusion.UI.Xaml.TreeView.SfTreeView.html#Syncfusion_UI_Xaml_TreeView_SfTreeView_ItemDragStarting), [SfTreeView.ItemDropping](https://help.syncfusion.com/cr/winui/Syncfusion.UI.Xaml.TreeView.SfTreeView.html#Syncfusion_UI_Xaml_TreeView_SfTreeView_ItemDropping) and [SfTreeView.ItemDropped](https://help.syncfusion.com/cr/winui/Syncfusion.UI.Xaml.TreeView.SfTreeView.html#Syncfusion_UI_Xaml_TreeView_SfTreeView_ItemDropped) events.
+
+``` csharp
+AssociatedObject.sfTreeView1.ItemDragStarting += SfTreeView1_ItemDragStarting;    
+AssociatedObject.sfTreeView1.ItemDropping += SfTreeView1_ItemDropping;
+AssociatedObject.sfTreeView2.ItemDropping += SfTreeView2_ItemDropping;
+AssociatedObject.sfTreeView2.ItemDropped += SfTreeView1_ItemDropped;
+    
+/// <summary>
+/// Customizing the ItemStarting event
+/// </summary>
+/// <param name="sender"></param>
+/// <param name="e"></param>
+private void SfTreeView1_ItemDragStarting(object sender, Syncfusion.UI.Xaml.TreeView.TreeViewItemDragStartingEventArgs e)
+{
+    //Restrict the dragging for certain node
+    var record = e.DraggingNodes[0].Content as Model;
+    if (record.Header == "Feature Schedule")
+        e.Cancel = true;
+}
+
+/// <summary>
+/// Customizing the ItemDropping event
+/// </summary>
+/// <param name="sender"></param>
+/// <param name="e"></param>
+private void SfTreeView1_ItemDropping(object sender, Syncfusion.UI.Xaml.TreeView.TreeViewItemDroppingEventArgs e)
+{
+    //Restrict the dropping in first treeview
+    e.Handled = true;
+}
+
+/// <summary>
+/// Customizing the ItemDropping event
+/// </summary>
+/// <param name="sender"></param>
+/// <param name="e"></param>
+private void SfTreeView2_ItemDropping(object sender, Syncfusion.UI.Xaml.TreeView.TreeViewItemDroppingEventArgs e)
+{
+    //Restrict the dropping for drop position as above
+    if (e.DropPosition == Syncfusion.UI.Xaml.TreeView.DropPosition.DropAbove)
+        e.Handled = true;
+
+    //Restrict the dropping on certain nodes
+    var record = e.TargetNode.Content as Model;
+    if (record.Header == "My Folders")
+        e.Handled = true;
+}
+
+/// <summary>
+/// Customize the ItemDropped event
+/// </summary>
+/// <param name="sender"></param>
+/// <param name="e"></param>
+private void SfTreeView1_ItemDropped(object sender, Syncfusion.UI.Xaml.TreeView.TreeViewItemDroppedEventArgs e)
+{
+    var parentNode = e.TargetNode.ParentNode;
+    var collection = parentNode.ChildNodes;
+    var record = e.DraggingNodes[0].Content as Model;
+    int count = 0;
+    foreach (var child in parentNode.ChildNodes)
+    {
+        var childNode = child.Content as Model;
+        if (childNode.Header == record.Header)
+        {
+            count++;
+            if (count > 1)
+            {
+            // Remove dropped node if the parent has the same node in it
+                collection.Remove(child);
+                return;
+            }
+        }
+    }
+}
+```