[Solved] RadDragAndDropManager.AddDropQueryHandler(tree, OnDropInsideTreeViewQuery)

[Tim]

I am trying to use this example: http://www.telerik.com/help/silverlight/radtreeview-how-to-enabled-drop-inside-only.html, but the OnDropInsideTreeViewQuery never gets called.  I am using the Q3_2009_1208 (SP1) release.

I have a breakpoint to confirm the RadDragAndDropManager.AddDropQueryHandler(tree, handler) gets called, but the breakpoint in handler is never hit.

I would expect this small example to work, based on the help document.

Tim

<UserControl x:Class="SilverlightApplication10.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:Controls="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.Navigation"
    mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480">
  <Grid x:Name="LayoutRoot">
        <Controls:RadTreeView
            IsVirtualizing="True"
            Grid.Row="0" Grid.Column="0"
            x:Name="SelectionTree"
            SelectionMode="Single"
            IsDragDropEnabled="True">
        </Controls:RadTreeView>
    </Grid>
</UserControl>

using System.Collections.ObjectModel;
using Telerik.Windows.Controls;
using Telerik.Windows.Controls.DragDrop;
using Telerik.Windows.Controls.TreeView;

namespace SilverlightApplication10
{
    public partial class MainPage
    {
        public MainPage()
        {
            InitializeComponent();
            SelectionTree.ItemsSource = new ObservableCollection<string>() {"One", "Two", "Three"};
            RadDragAndDropManager.AddDropQueryHandler(SelectionTree, OnDropInsideTreeViewQuery);
        }

        private void OnDropInsideTreeViewQuery(object sender, DragDropQueryEventArgs e)
        {
            RadTreeViewItem treeViewItem = e.Options.Destination as RadTreeViewItem;
            TreeViewDragCue cue = e.Options.DragCue as TreeViewDragCue;

            if (e.Options.Destination is RadTreeView ||
                (treeViewItem.Level == 0 && cue.IsDropPossible &&
                treeViewItem.DropPosition != DropPosition.Inside))
            {
                e.QueryResult = false;
            }
        }
    }
}

[Kiril Stanoev]

Hi Tim,

Indeed following the steps of this article does to enable dropping only inside. We are currently working on updating our help articles and we will make sure to fix this one as well. Meanwhile, please find attached a sample project that demonstrates how to enable dropping only inside a node. If you have any questions or comments, I'd be glad to further assist you. I have also added 500 Telerik points to your account.

Greetings,
Kiril Stanoev
the Telerik team

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[Tim]

All set, thanks!