Silverlight ListBox拖放

1.ListBox在没有添加任何Item是的拖放可以完全参照Button的拖放
2.当ListBox添加了Item时，会出现ListBox不相应listBox1_MouseLeftButtonDown的问题
解决方法:
原因： ListBox中，MouseLeftButtonDown事件是一个RoutedEvent,并且在routing过程中被标记为handled， 因此ListBox不会再抛出该事件，因此你的事件处理方法也无从相应。

解决： 使用UIElement.AddHandler 方法指定已经被handled的事件。

        bool trackingMouseMove = false;
        Point mousePosition;

       public listBox添加项后的拖放()
        {
            InitializeComponent();           
            listBox1.AddHandler(ListBox.MouseLeftButtonDownEvent,
                new MouseButtonEventHandler(listBox1_MouseLeftButtonDown),true);
            //listBox1.AddHandler(ListBox.MouseLeftButtonUpEvent,
            //    new MouseButtonEventHandler(listBox1_MouseLeftButtonUp),true);
            //注意MouseMove不需要添加,只需要添加MouseLeftButtonDown即可
        }

 

        private void listBox1_MouseLeftButtonDown(object sender,MouseButtonEventArgs e)
        {
            FrameworkElement element = sender as FrameworkElement;
            mousePosition = e.GetPosition(null);
            trackingMouseMove = true;
            if (null != element)
            {
                element.CaptureMouse();
                element.Cursor = Cursors.Hand;
            }
        }   

       private void listBox1_MouseLeftButtonUp(object sender,MouseButtonEventArgs e)
        {
            FrameworkElement element = sender as FrameworkElement;
            trackingMouseMove = false;
            element.ReleaseMouseCapture();

            mousePosition.X = mousePosition.Y = 0;
            element.Cursor = null;
        }

        private void listBox1_MouseMove(object sender,MouseEventArgs e)
        {
            FrameworkElement element = sender as FrameworkElement;
            if (trackingMouseMove)
            {
                double deltaV = e.GetPosition(null).Y - mousePosition.Y;
                double deltaH = e.GetPosition(null).X - mousePosition.X;
                double newTop = deltaV + (double)element.GetValue(Canvas.TopProperty);
                double newLeft = deltaH + (double)element.GetValue(Canvas.LeftProperty);

                element.SetValue(Canvas.TopProperty,newTop);
                element.SetValue(Canvas.LeftProperty,newLeft);

                mousePosition = e.GetPosition(null);
            }
        }
3.===================拖放一个ListBox的Item到另外一个ListBox===============
主要代码
   public partial class listBox拖放Item : Page
    {
        bool trackingMouseMove = false;
        Point mousePosition;
        double newTop;
        double newLeft;

        public listBox拖放Item()
        {
            InitializeComponent();
            listBox1.AddHandler(ListBox.MouseLeftButtonDownEvent,true);
            //注意此处不能加listBox1_MouseLeftButtonUp的处理了，否则MouseLeftButtonUp会被触发两次
            //listBox1.AddHandler(ListBox.MouseLeftButtonUpEvent,true);
        }

        // 当用户导航到此页面时执行。
        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
        }

        private void Page_Loaded(object sender,RoutedEventArgs e)
        {
            listBox1.Items.Clear();
            listBox1.Items.Add("选项1");
            listBox1.Items.Add("选项2");
            listBox1.Items.Add("选项3");
        }

        private void listBox1_MouseLeftButtonDown(object sender,MouseButtonEventArgs e)
        {
            FrameworkElement element = sender as FrameworkElement;
            mousePosition = e.GetPosition(null);
            trackingMouseMove = true;
            if (null != element)
            {
                element.CaptureMouse();
                element.Cursor = Cursors.Hand;
            }
        }

        private void listBox1_MouseLeftButtonUp(object sender,MouseButtonEventArgs e)
        {
            double dblListBox2Left = (double)listBox2.GetValue(Canvas.LeftProperty);
            double dblListBox2Top = (double)listBox2.GetValue(Canvas.TopProperty);
            if (newLeft >= dblListBox2Left && newLeft <= (dblListBox2Left + listBox2.Width))
            {
                if (newTop >= dblListBox2Top && newTop <= (dblListBox2Top + listBox2.Height))
                {
                    listBox2.Items.Add(listBox1.SelectedItem.ToString());
                }
            }
            FrameworkElement element = sender as FrameworkElement;
            trackingMouseMove = false;
            element.ReleaseMouseCapture();
            //清空坐标
            newTop = 0;
            newLeft = 0;
            element.Cursor = null;
        }

        private void listBox1_MouseMove(object sender,MouseEventArgs e)
        {
            FrameworkElement element = sender as FrameworkElement;
            if (trackingMouseMove)
            {
                //记录鼠标位置
                newTop = e.GetPosition(null).Y;
                newLeft = e.GetPosition(null).X;
            }
        }

    }

 

xaml代码
<navigation:Page x:Class="Silverlight拖放.listBox添加项后的拖放"
           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"            mc:Ignorable="d"            xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation"            d:DesignWidth="640" d:DesignHeight="480"            Title="listBox添加项后的拖放 Page" Loaded="Page_Loaded">     <Canvas Background="#46461F">         <ListBox Canvas.Left="27" Canvas.Top="23" Height="187" Name="listBox1" Width="187" SelectionMode="Multiple" MouseLeftButtonDown="listBox1_MouseLeftButtonDown" MouseLeftButtonUp="listBox1_MouseLeftButtonUp" MouseMove="listBox1_MouseMove" />     </Canvas> </navigation:Page>