从一个ListBox到另一个ListBox动画ListBoxItem

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.ColumnDefinitions>
           <ColumnDefinition/>
           <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <ListBox x:Name="ListBox1" Margin="10" SelectionMode="Extended">
            <ListBox.Items>
                <ListBoxItem Content="Item 1"/>
                <ListBoxItem Content="Item 2"/>
                <ListBoxItem Content="Item 3"/>
            </ListBox.Items>
        </ListBox>
        <ListBox x:Name="ListBox2" Margin="10" Grid.Column="1" SelectionMode="Extended">
            <ListBox.Items>
                <ListBoxItem Content="Item 4"/>
                <ListBoxItem Content="Item 5"/>
                <ListBoxItem Content="Item 6"/>
            </ListBox.Items>
        </ListBox>
       <Storyboard x:Key="MoveItemAnimation">
           <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[3].(TranslateTransform.X)" Storyboard.TargetName="movingItem">
                <SplineDoubleKeyFrame KeyTime="0" Value="0"/>
                <SplineDoubleKeyFrame KeyTime="0:0:1" Value="100"/>
            </DoubleAnimationUsingKeyFrames>
        </Storyboard>
    </Grid>
</Window>

using System.Windows;
using System.Windows.Media;

namespace WpfApp1
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void ListBox_SelectionChanged(object sender, System.Windows.Controls.SelectionChangedEventArgs e)
        {
            var selectedItems = (sender as ListBox).SelectedItems;
            if (selectedItems.Count > 0)
            {
                var movingItem = selectedItems[0] as ListBoxItem;
                var storyboard = FindResource("MoveItemAnimation") as Storyboard;
                var animation = storyboard.Children[0] as DoubleAnimationUsingKeyFrames;
                animation.Completed += (s, e2) =>
                {
                    ListBox2.Items.Add(movingItem);
                    ListBox1.Items.Remove(movingItem);
                };
                storyboard.Begin(movingItem);
            }
        }
    }
}