稳扎稳打Silverlight(37) - 3.0动画之Easing（缓动效果）

[索引页]
[源码下载]

稳扎稳打Silverlight(37) - 3.0动画之Easing（缓动效果）

作者：webabcd


介绍
Silverlight 3.0 动画的缓动效果：

• Easing 可以与 Storyboard 结合实现动画的缓动效果
• Silverlight 3 内置 11 种缓动效果：分别为BackEase, BounceEase, CircleEase, CubicEase, ElasticEase, ExponentialEase, PowerEase, QuadraticEase, QuarticEase, QuinticEase, SineEase
• 各个缓动类都继承自 EasingFunctionBase，除了 EasingFunctionBase 提供的功能外，各个缓动类可能还会有各自的属性（懒的写了，查文档吧） 
• EasingFunctionBase 有一个用于设置缓动模式的枚举类型属性 EasingMode （EasingMode.EaseOut(默认值), EasingMode.EaseIn, EasingMode.EaseInOut）

在线DEMO
http://webabcd.blog.51cto.com/1787395/342289


示例
1、Silverlight 3.0 内置的 11 种缓动效果的 Demo
Easing.xaml

<navigation:Page x:Class="Silverlight30.Animation.Easing"    
                     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="Easing Page">
        <Grid x:Name="LayoutRoot">
                <StackPanel Orientation="Horizontal" HorizontalAlignment="Left">

                        <!--用于显示各种 Easing 的图例列表-->
                        <StackPanel Margin="10">
                                <ListBox x:Name="lstEasing">
                                        <ListBox.ItemTemplate>
                                                <DataTemplate>
                                                        <StackPanel Margin="1">
                                                                <TextBlock Text="{Binding EasingName}" />
                                                                <Image Source="{Binding PicAddress}" Width="300" Height="50" />
                                                        </StackPanel>
                                                </DataTemplate>
                                        </ListBox.ItemTemplate>
                                </ListBox>
                        </StackPanel>

                        <StackPanel Margin="10, 200">
                        
                                <!--分别用 3 种动画来演示各类 Easing-->
                                <ComboBox x:Name="cboTransform" Margin="5">
                                        <ComboBoxItem Content="Translate" IsSelected="True" />
                                        <ComboBoxItem Content="Rotate" />
                                        <ComboBoxItem Content="Scale" />
                                </ComboBox>
                                
                                <!--用各种 EasingMode 分别做演示-->
                                <ComboBox x:Name="cboEasingMode" Margin="5">
                                        <ComboBoxItem Content="EaseOut" IsSelected="True" />
                                        <ComboBoxItem Content="EaseIn" />
                                        <ComboBoxItem Content="EaseInOut" />
                                </ComboBox>

                                <Button x:Name="btnShow" Content="演示" Click="btnShow_Click" Margin="5" />

                                <!--用于做动画演示的矩形-->
                                <Rectangle x:Name="rect" Fill="Blue" Width="200" Height="40" Margin="5" RenderTransformOrigin="0.5,0.5">
                                        <Rectangle.RenderTransform>
                                                <TransformGroup>
                                                        <TranslateTransform x:Name="tt" X="0" Y="0" />
                                                        <RotateTransform x:Name="rt" Angle="0" />
                                                        <ScaleTransform x:Name="st" ScaleX="1" ScaleY="1" />
                                                </TransformGroup>
                                        </Rectangle.RenderTransform>
                                </Rectangle>

                        </StackPanel>
                </StackPanel>
        </Grid>
</navigation:Page>

 

Easing.xaml.cs

/*
* Easing - 与 Storyboard 结合实现动画的缓动效果
* Silverlight 3 内置 11 种缓动效果：分别为BackEase, BounceEase, CircleEase, CubicEase, ElasticEase, ExponentialEase, PowerEase, QuadraticEase, QuarticEase, QuinticEase, SineEase
* 各个缓动类都继承自 EasingFunctionBase，除了 EasingFunctionBase 提供的功能外，各个缓动类可能还会有各自的属性（懒的写了，查文档吧）
* EasingFunctionBase 有一个用于设置缓动模式的枚举类型属性 EasingMode （EasingMode.EaseOut(默认值), EasingMode.EaseIn, EasingMode.EaseInOut）
*/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Navigation;

using Silverlight30.Model;
using System.Xml.Linq;

namespace Silverlight30.Animation
{
         public partial class Easing : Page
        {
                 public Easing()
                {
                        InitializeComponent();

                         this.Loaded += new RoutedEventHandler(Easing_Loaded);
                }

                 // 绑定各种 Easing 的图例列表
                 void Easing_Loaded( object sender, RoutedEventArgs e)
                {
                        XElement root = XElement.Load( "Animation/Easing.xml");
                        var easings = from n in root.Elements( "easing")
                                                    select new EasingModel
                                                    {
                                                            EasingName = ( string)n.Attribute( "EasingName"),
                                                            Description = ( string)n.Attribute( "Description"),
                                                            PicAddress = ( string)n.Attribute( "PicAddress")
                                                    };

                        lstEasing.ItemsSource = easings;
                        lstEasing.SelectedIndex = 0;
                }

                 private Storyboard _prevStoryboard;

                 private void btnShow_Click( object sender, RoutedEventArgs e)
                {
                         if (_prevStoryboard != null)
                                _prevStoryboard.Stop();

                         // 实例化用户所选择的 Easing
                        Type type = typeof(EasingFunctionBase).Assembly.GetType( "System.Windows.Media.Animation." + ((EasingModel)lstEasing.SelectedItem).EasingName, false);
                        EasingFunctionBase easing = Activator.CreateInstance(type) as EasingFunctionBase;

                         // 根据用户的选择，设置 Easing 的 EasingMode 属性
                        easing.EasingMode = (EasingMode)Enum.Parse( typeof(EasingMode), ((ComboBoxItem)cboEasingMode.SelectedItem).Content.ToString(), true);

                        Storyboard sb = new Storyboard();
                        _prevStoryboard = sb;

                        var transformType = ((ComboBoxItem)cboTransform.SelectedItem).Content.ToString();
                         switch (transformType)
                        {
                                 // 位移动画结合 Easing 的演示
                                 case "Translate":
                                        DoubleAnimation daTranslateY = new DoubleAnimation();
                                        daTranslateY.From = 0 ;
                                        daTranslateY.To = 200;
                                        daTranslateY.Duration = TimeSpan.FromSeconds(3);

                                        daTranslateY.EasingFunction = easing;

                                        Storyboard.SetTargetProperty(daTranslateY, new PropertyPath( "Y"));
                                        Storyboard.SetTarget(daTranslateY, tt);

                                        sb.Children.Add(daTranslateY);

                                         break;
                                 // 缩放动画结合 Easing 的演示
                                 case "Scale":
                                        DoubleAnimation daScaleX = new DoubleAnimation();
                                        daScaleX.From = 1;
                                        daScaleX.To = 2;
                                        daScaleX.Duration = TimeSpan.FromSeconds(3);

                                        DoubleAnimation daScaleY = new DoubleAnimation();
                                        daScaleY.From = 1;
                                        daScaleY.To = 2;
                                        daScaleY.Duration = TimeSpan.FromSeconds(3);

                                        daScaleX.EasingFunction = easing;
                                        daScaleY.EasingFunction = easing;

                                        Storyboard.SetTargetProperty(daScaleX, new PropertyPath( "ScaleX"));
                                        Storyboard.SetTarget(daScaleX, st);
                                        Storyboard.SetTargetProperty(daScaleY, new PropertyPath( "ScaleY"));
                                        Storyboard.SetTarget(daScaleY, st);

                                        sb.Children.Add(daScaleX);
                                        sb.Children.Add(daScaleY);

                                         break;
                                 // 旋转动画结合 Easing 的演示
                                 case "Rotate":
                                        DoubleAnimation daAngle = new DoubleAnimation();
                                        daAngle.To = 0;
                                        daAngle.To = 360;
                                        daAngle.Duration = TimeSpan.FromSeconds(3);

                                        daAngle.EasingFunction = easing;

                                        Storyboard.SetTargetProperty(daAngle, new PropertyPath( "Angle"));
                                        Storyboard.SetTarget(daAngle, rt);

                                        sb.Children.Add(daAngle);

                                         break;
                        }
        
                        sb.Begin();
                }
        }
}

 

 

2、自定义缓动效果的 Demo
MyCustomEasing.cs

using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace Silverlight30.Animation
{
         /// <summary>
         /// 自定义缓动效果
         /// </summary>
         public class MyCustomEasing : EasingFunctionBase
        {
                 public MyCustomEasing()
                        : base()
                {
    
                }

                 /// <summary>
                 /// 实现 EaseIn 模式下的逻辑
                 /// EaseOut 和 EaseInOut 会自动实现
                 /// </summary>
                 /// <param name="normalizedTime">标准时间位（0 - 1之间）。即 动画运行到此的时间 占 动画运行所需的全部时间 的百分比</param>
                 /// <returns></returns>
                 protected override double EaseInCore( double normalizedTime)
                {
                         // QuinticEase 效果的实现算法

                         // 假定动画运行的总共时间为 1 秒
                         // 那么当 normalizedTime 为 0.1 时，动画运行到的位置为无该缓动效果时，0.00001秒后的位置。以此类推
                         return Math.Pow(normalizedTime, 5);
                }
        }
}

 

CustomEasing.xaml

<navigation:Page x:Class="Silverlight30.Animation.CustomEasing"    
                     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:custom="clr-namespace:Silverlight30.Animation"
                     xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation"
                     d:DesignWidth="640" d:DesignHeight="480"
                     Title="CustomEasing Page">
        <Grid x:Name="LayoutRoot">
                <StackPanel>
                
                        <StackPanel.Resources>
                                <Storyboard x:Name="ani">
                                        <DoubleAnimation    
                                                Storyboard.TargetName="tt"
                                                Storyboard.TargetProperty="Y"
                                                From="0"    
                                                To="200"    
                                                Duration="00:00:03"
                                        >
                                                <DoubleAnimation.EasingFunction>
                                                        <!--使用自定义的缓动效果-->
                                                        <custom:MyCustomEasing EasingMode="EaseOut" />
                                                </DoubleAnimation.EasingFunction>
                                        </DoubleAnimation>
                                </Storyboard>
                        </StackPanel.Resources>

                        <Button x:Name="btnShow" Content="演示" Margin="5" Click="btnShow_Click" />

                        <Rectangle x:Name="rect" Fill="Blue" Width="200" Height="40" Margin="5" RenderTransformOrigin="0.5,0.5">
                                <Rectangle.RenderTransform>
                                        <TransformGroup>
                                                <TranslateTransform x:Name="tt" X="0" Y="0" />
                                        </TransformGroup>
                                </Rectangle.RenderTransform>
                        </Rectangle>
                        
                </StackPanel>
        </Grid>
</navigation:Page>

 

CustomEasing.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Navigation;

namespace Silverlight30.Animation
{
         public partial class CustomEasing : Page
        {
                 public CustomEasing()
                {
                        InitializeComponent();
                }

                 private void btnShow_Click( object sender, RoutedEventArgs e)
                {
                        ani.Begin();
                }
        }
}

 

OK
[源码下载]