e.Options.Destination property always returns tree root node.

[SangGyu Kim]

I find strange thing in Drop Query Handler Method to drop the TreeView Control (not RadTreeView)

e.Options.Destination property always returns tree root node

How can I get the TreeViewItem object that I dropped?

 

        private void OnTreeDropQuery(object sender, DragDropQueryEventArgs e)
        {
            var destinationItem = e.Options.Destination as TreeViewItem;  <-- always returns "Root" node item
            var sourceItem = e.Options.Source as Control;

            Debug.WriteLine("OnTreeDropQuery " + ((Label)((StackPanel)destinationItem.Header).Children[1]).Content);
            if (e.Options.Status == DragStatus.DropDestinationQuery)
            {
                if (destinationItem != null && destinationItem != sourceItem)
                {
                    //Debug.WriteLine("OnTreeDropQuery Drop Query Item Tag :" + destinationItem);
                    var storageItem = destinationItem.DataContext as SPStorageItem;
                    var isStorageItemNode = storageItem != null;

                    e.QueryResult = isStorageItemNode;
                    e.Handled = isStorageItemNode;
                }
                else
                {
                    e.QueryResult = false;
                }
            }
        }

       <basics:TreeView x:Name="tvNavigation" GotFocus="tvNavigation_GotFocus" SelectedItemChanged="tvNavigatin_SelectedItemChanged"
                          Grid.Row="2"
                          Grid.Column="0"
                          VerticalAlignment="Stretch"
                          HorizontalAlignment="Stretch"
                         KeyUp="tvNavigation_KeyUp"
                         KeyDown="tvNavigation_KeyDown"
                         >
            <basics:TreeView.ItemContainerStyle>
                <Style TargetType="basics:TreeViewItem">
                    <Setter Property="dragDrop:RadDragAndDropManager.AllowDrag" Value="True" />
                    <Setter Property="dragDrop:RadDragAndDropManager.AllowDrop" Value="True" />
                    <Setter Property="Foreground" Value="Red" />
                </Style>
            </basics:TreeView.ItemContainerStyle>

            <basics:TreeViewItem IsExpanded="True" Tag="My Computer" >
                <basics:TreeViewItem.Header>
                    <StackPanel Orientation="Horizontal">
                        <Image Source="../../Image/computer24.png"></Image>
                        <Controls:Label Content=" My Computer" VerticalAlignment="Center"></Controls:Label>
                    </StackPanel>
                </basics:TreeViewItem.Header>
                <basics:TreeViewItem Tag="Online" >
                    <basics:TreeViewItem.Header>
                        <StackPanel Orientation="Horizontal">
                            <Image Source="../../Image/disc24.png"></Image>
                            <Controls:Label Content=" Online Storage"></Controls:Label>
                        </StackPanel>
                    </basics:TreeViewItem.Header>
                </basics:TreeViewItem>
                <basics:TreeViewItem Tag="Local">
                    <basics:TreeViewItem.Header>
                        <StackPanel Orientation="Horizontal">
                            <Image Source="../../Image/mydoc24.png"></Image>
                            <Controls:Label Content=" Offline Storage"></Controls:Label>
                        </StackPanel>
                    </basics:TreeViewItem.Header>
                </basics:TreeViewItem>
                <basics:TreeViewItem Tag="휴지통">
                    <basics:TreeViewItem.Header>
                        <StackPanel Orientation="Horizontal">
                            <Image Source="../../Image/recyclebin24.png"></Image>
                            <Controls:Label Content=" 휴지통" VerticalAlignment="Center"></Controls:Label>
                        </StackPanel>
                    </basics:TreeViewItem.Header>
                </basics:TreeViewItem>
            </basics:TreeViewItem>
        </basics:TreeView>

[SangGyu Kim]

I solve the problem. ^^
Sub item nodes are created dynamically and I didn't set RadDragAndDropManager.AllowDropProperty property value.

                foreach (SPStorageItem item in dirs.Where(o => o.IsFolder))
                {
                    TreeViewItem item2 = new TreeViewItem();
                    item2.DataContext = item;
                    item2.SetValue(RadDragAndDropManager.AllowDropProperty, true);
                    treeViewItem.Items.Add(item2);
                }