<localControls:BranchNode Grid.Column="0" x:Name="unAllocateBranchNode" Margin="30">
            <localControls:BranchNode.Template>
                <ControlTemplate TargetType="localControls:BranchNode">
                    <Grid x:Name="rootPanel" VerticalAlignment="Top" Height="{TemplateBinding Height}">
                        <StackPanel Orientation="Vertical" HorizontalAlignment="Stretch" DataContext="{TemplateBinding Branch}">
                            <Border x:Name="titlePanel" HorizontalAlignment="Stretch"  Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" CornerRadius="3" BorderThickness="1">
                                <Border.Resources>
                                    <SolidColorBrush x:Key="normalBorder" Color="#9fa8b7"/>
                                    <SolidColorBrush x:Key="hightlightBorder" Color="Red"/>
                                </Border.Resources>
                                <StackPanel>
                                    <StackPanel Orientation="Horizontal">
                                        <ContentPresenter Content="{Binding Name}" VerticalAlignment="Center" Margin="5"/>                        
                                    </StackPanel>

                                    <ItemsControl ItemsSource="{Binding Embranchment}">
                                        <ItemsControl.ItemsPanel>
                                            <ItemsPanelTemplate>
                                                <StackPanel/>
                                            </ItemsPanelTemplate>
                                        </ItemsControl.ItemsPanel>
                                        <ItemsControl.ItemTemplate>
                                            <DataTemplate>
                                                <localControls:BranchNode Branch="{Binding}" Margin="3"/>
                                            </DataTemplate>
                                        </ItemsControl.ItemTemplate>
                                    </ItemsControl>

                                </StackPanel>

                            </Border>
                        </StackPanel>
                    </Grid>
                </ControlTemplate>
            </localControls:BranchNode.Template>
        </localControls:BranchNode>

            Branch branch = new Branch();
            branch.Name = "财务部";

            branch.Embranchment = new ObservableCollection<Branch>()
            {
                new Branch(){Name="财务部1"},
                new Branch(){Name="财务部2"},
                new Branch(){Name="财务部3"}
            };

            
            branch.AppendBranch += new Action<Branch>(branch_AppendBranch);
            this.unAllocateBranchNode.Branch = branch;

        private void BindDragEvent()
        {
            bool isDragging = false;
            Point lastPosition = new Point(0, 0);

            Popup rootPopup = new Popup();
            BranchNode ghostContainer = null;

            Branch parentBranch = null;
            Border lastTitlePanel = null;

            ...
            this.titlePanel.MouseLeftButtonDown += (source, eventArgs) =>
            {
                this.IsHitTestVisible = false;

                isDragging = true;
                lastPosition = eventArgs.GetPosition(null);
                ...
                ghostContainer.MouseLeftButtonUp += (s, e) =>
                {   
                    rootPopup.Child = null;
                    ...
                    isDragging = false;
                    this.ReleaseMouseCapture();
                    this.IsHitTestVisible = true;
                };

                ghostContainer.MouseMove += (s, e) =>
                {
                    if (!isDragging)
                        return;

                    ...
                    MatrixTransform mt = new MatrixTransform();
                    mt.Matrix = rt.Value;

                    ghostContainer.RenderTransform = mt;

                };
            };
        }