原文:示例：WPF中自定义StoryBoarService在代码中封装StoryBoard、Animation用于简化动画编写

一、目的：通过对StoryBoard和Animation的封装来简化动画的编写

 

二、示例：

说明：渐隐藏是WPF中比较常用的动画，上图是通过StoryBoarService封装后的效果，在代码中只要执行如下代码即可：

 DoubleStoryboardEngine.Create(1, 0, 1, "Opacity").Start(element);

上面的关闭效果可以定义一个命令如下：

    public class CollapsedOfOpacityCommand : ICommand
    {
 
        public bool CanExecute(object parameter) => true;
 
        public void Execute(object parameter)
        {
            if(parameter is UIElement element)
            {
                var engine = DoubleStoryboardEngine.Create(1, 0, 1, "Opacity");
 
                engine.Start(element);
            }
        }
 
        public event EventHandler CanExecuteChanged;
    }

在Xaml中调用如下命令即可完成关闭渐隐藏的效果

Command="{x:Static base:CommandService.CollapsedOfOpacityCommand}"
CommandParameter="{Binding RelativeSource={RelativeSource AncestorType=GroupBox}}"

传入的CommandParmeter将会在执行命令时渐隐藏

 

其中动画效果的代码只需一句代码即可，简化了动画在代码中繁琐的编码过程

 DoubleStoryboardEngine.Create(1, 0, 1, "Opacity").Start(element);

  二、代码：

目前只实现DoubleAnimation的封装，后续将会对其他类型进行封装

1、封闭修改基类

    /// <summary> 动画引擎基类 </summary>
    public abstract class StoryboardEngineBase : IDisposable
    {
        protected Storyboard storyboard = new Storyboard();
 
        public EventHandler CompletedEvent { get; set; }
 
        public EasingFunctionBase Easing { get; set; } = EasingFunctionFactroy.PowerEase;
 
        public PropertyPath PropertyPath { get; set; }
 
        public Duration Duration { get; set; }
 
        public void Dispose()
        {
            storyboard.Completed -= CompletedEvent;
        }
 
        public abstract StoryboardEngineBase Start(UIElement element);
 
        public abstract StoryboardEngineBase Stop();
 
        public StoryboardEngineBase(int second, string property)
        {
            this.PropertyPath = new PropertyPath(property);
            this.Duration = new Duration(TimeSpan.FromSeconds(second));
        }
 
    }
 
    /// <summary> 动画泛型引擎基类 </summary>
    public abstract class StoryboardEngineBase<T> : StoryboardEngineBase
    {
        public StoryboardEngineBase(T from, T to, int second, string property) : base(second, property)
        {
            this.FromValue = from;
            this.ToValue = to;
        }
 
        public T FromValue { get; set; }
 
        public T ToValue { get; set; }
 
        //public RepeatBehavior RepeatBehavior { get; set; };
 
    }

2、开放扩展DoubleStoryboardEngine

    /// <summary> DoubleAnimation动画引擎 </summary>
    public class DoubleStoryboardEngine : StoryboardEngineBase<double>
    {
        public static DoubleStoryboardEngine Create(double from, double to, int second, string property)
        {
            return new DoubleStoryboardEngine(from, to, second, property);
        }
 
        public DoubleStoryboardEngine(double from, double to, int second, string property) : base(from, to, second, property)
        {
 
        }
 
        public override StoryboardEngineBase Start(UIElement element)
        {
            //  Do：时间线
            DoubleAnimation animation = new DoubleAnimation(1, 0, this.Duration);
 
            if (this.Easing != null)
                animation.EasingFunction = this.Easing;
 
            //if (this.RepeatBehavior != default(RepeatBehavior))
            //    animation.RepeatBehavior = (RepeatBehavior);
 
            //  Do：属性动画
            storyboard.Children.Add(animation);
            Storyboard.SetTarget(animation, element);
            Storyboard.SetTargetProperty(animation, this.PropertyPath);
 
            if (CompletedEvent != null)
                storyboard.Completed += CompletedEvent;
            storyboard.Begin();
 
            return this;
        }
 
        public override StoryboardEngineBase Stop()
        {
            this.storyboard.Stop();
 
            return this;
        }
    }

3、过度效果工厂

    /// <summary> 说明：https://docs.microsoft.com/zh-cn/dotnet/framework/wpf/graphics-multimedia/easing-functions </summary>
    public static class EasingFunctionFactroy
    {
        /// <summary> PowerEase：创建加速和/或减速使用的公式的动画f(t) = tp其中 p 等于Power属性。 </summary>
        public static PowerEase PowerEase { get; set; } = new PowerEase();
        /// <summary> BackEase：略微收回动画的动作，然后再开始进行动画处理指示的路径中。 </summary>
        public static BackEase BackEase { get; set; } = new BackEase();
        /// <summary> ElasticEase：创建类似于弹簧来回直到静止的动画 </summary>
        public static ElasticEase ElasticEase { get; set; } = new ElasticEase();
        /// <summary> BounceEase：创建弹跳效果。 </summary>
        public static BounceEase BounceEase { get; set; } = new BounceEase();
        /// <summary> CircleEase：创建加速和/或减速使用循环函数的动画。 </summary>
        public static CircleEase CircleEase { get; set; } = new CircleEase();
 
        /// <summary> QuadraticEase：创建加速和/或减速使用的公式的动画f(t) = t2。 </summary>
        public static QuadraticEase QuadraticEase { get; set; } = new QuadraticEase();
 
        /// <summary> CubicEase：创建加速和/或减速使用的公式的动画f(t) = t3。 </summary>
        public static CubicEase CubicEase { get; set; } = new CubicEase();
        /// <summary> QuarticEase：创建加速和/或减速使用的公式的动画f(t) = t4。 </summary>
        public static QuarticEase QuarticEase { get; set; } = new QuarticEase();
        /// <summary> QuinticEase：创建加速和/或减速使用的公式的动画f(t) = t5。 </summary>
        public static QuinticEase QuinticEase { get; set; } = new QuinticEase();
 
        /// <summary> ExponentialEase：创建加速和/或减速使用指数公式的动画。 </summary>
        public static ExponentialEase ExponentialEase { get; set; } = new ExponentialEase();
 
        /// <summary> SineEase：创建加速和/或减速使用正弦公式的动画。 </summary>
        public static SineEase SineEase { get; set; } = new SineEase();
 
    }

4、使用方法：

        /// <summary> 构造方法 </summary>
        /// <param name="from"> 起始值</param>
        /// <param name="to"> 结束值  </param>
        /// <param name="second"> 间隔时间秒 </param>
        /// <param name="property"> 修改属性名称 </param>
        /// 
        public static DoubleStoryboardEngine Create(double from, double to, int second, string property)
        {
            return new DoubleStoryboardEngine(from, to, second, property);
        }

下载地址：https://github.com/HeBianGu/WPF-ControlBase.git