兑现一个动画

实现一个动画
在mainpage里面，点击按钮 ，一个usercontrol从下到上慢慢浮现，再点击一下，再从下到上慢慢隐藏，我本来想用渐变工具把usercontrol分成几块 然后调透明度，可是用渐变工具根本就没有分层，怎么弄，求个思路。
[解决办法]
不用什么渐变工具，用Storyboard，控制透明度和RenderTransform就可以。

<UserControl x:Class="SilverlightApplication1.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"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400">
    
    <Grid Margin="5" HorizontalAlignment="Center" VerticalAlignment="Center">
        <Grid.RowDefinitions>
            <RowDefinition />
            <RowDefinition Height="5"/>
            <RowDefinition Height="45"/>
        </Grid.RowDefinitions>
        
        <Grid.Resources>
            
            <Storyboard x:Name="storyboard1">
                <DoubleAnimation Duration="0:0:3" To="-100" Storyboard.TargetName="test" Storyboard.TargetProperty="Y"/>
                <DoubleAnimation Duration="0:0:3" To="1" Storyboard.TargetName="btn1" Storyboard.TargetProperty="Opacity"/>
            </Storyboard>

            <Storyboard x:Name="storyboard2">
                <DoubleAnimation Duration="0:0:3" To="0" Storyboard.TargetName="test" Storyboard.TargetProperty="Y"/> 
 
                <DoubleAnimation Duration="0:0:3" To="0" Storyboard.TargetName="btn1" Storyboard.TargetProperty="Opacity"/>
            </Storyboard>
            
        </Grid.Resources>

        <Button x:Name="btn1" FontSize="15" Content="O(∩_∩)O" HorizontalAlignment="Center" VerticalAlignment="Bottom" Opacity="0" Margin="157,0,163,10">
            <Button.RenderTransform>
                <TranslateTransform x:Name="test"/>
            </Button.RenderTransform>
        </Button>

        <Button FontSize="15" Content="启动动画" Grid.Row="2" HorizontalAlignment="Center" VerticalAlignment="Center" Click="Button_Click" />

    </Grid>
</UserControl>

using System;
using System.Windows;
using System.Windows.Controls;

namespace SilverlightApplication1
{
    public partial class MainPage : UserControl
    {
        private Int32 i = 0;

        public MainPage()
        {
            InitializeComponent();
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            i++;
            if (i % 2 == 0) {
                storyboard2.Begin();
            } else {
                storyboard1.Begin();
            }
        } 
 
    }
}