动画

动画是改变控件的一些属性，加一时间元素。通常结合“呈现变形”，即控件的RenderTransform来完成

一个元素可以完成的作画叫AnimationTimeLine，多个UI元素组合起来的叫Storyboard

简单动画就DoubleAnimationBase派生类用得最多

1.简单线性动画

几个重要属性：

变化时间(Duration)

变化终点(To属性)

变化幅度(By属性)

变化起点(From属性)

<Grid>

<Button.RenderTransform>

<TranslateTransform X="0" Y="0" x:Name="tt"/>

<!--

MatrixTransform矩陈变形

RotateTransform旋转变形

ScaleTransform坐标变形

SkewTransform拉伸变形

TranslateTransform偏移变形

TransformGroup变形组，多个独立变形合成一个变形组，产生复合效果

-->

</TransformGroup>

</Button.RenderTransform>

</Button>

</Grid>

private void button_Click(object sender, RoutedEventArgs e)

{

DoubleAnimation daX = new DoubleAnimation();

DoubleAnimation daY = new DoubleAnimation();

//若不想每都从0,0坐标开始，则不给From赋值就是从当前开始

daX.From = 0D;

daY.From = 0D;

daX.To = (new Random()).NextDouble() * 300;

daY.To = (new Random()).NextDouble() * 300;

Duration dr = new Duration(TimeSpan.FromMilliseconds(300));

daX.Duration = dr;

daY.Duration = dr;

this.tt.BeginAnimation(TranslateTransform.XProperty, daX);

//如果少了这条，则只是水平移动，没了y轴

this.tt.BeginAnimation(TranslateTransform.YProperty,daY);

}

其实就是给好目标的XY坐标值，然后元素向目标点走直线形成的动画

2.高级动画控制

就是多了几个属性:

AccelerationRatio 加速速率，介于0.00和1.0之间，与DecclerationRation之和不大于1.0，如模拟汽车启动

DecclerationRation减速速率，介于0.00和1.0之间，与AccelerationRatio 之和不大于1.0，如模拟汽车刹车

SpeedRation动画实际播放速度与正常速度的比值如快进播放、慢动作

AutoReverse 是否以相反的动画方式从终点值返回起始值如倒退播放

RepeatBehavior动画的重复行为，取0为不播放，使用double类型值可控制循环次数，取RepeatBehavior.Forever永不停

BeginTime正式开始播放前的等待时间常用于多个动画协同

EasingFunction缓冲式渐变如乒乓球弹跳效果

以下示例向乒乓球掉在地止弹起3次再停止

private void button_Click(object sender, RoutedEventArgs e)

{

DoubleAnimation daX = new DoubleAnimation();

DoubleAnimation daY = new DoubleAnimation();

daX.From = 0D;

daY.From = 0D;

BounceEase be = new BounceEase();

be.Bounces = 52;//跳跃3次

be.Bounciness = 2;//弹性程序，值越大反弹越低

daY.EasingFunction = be;

daX.To = 2 * 300;

daY.To = 2 * 300;

Duration dr = new Duration(TimeSpan.FromMilliseconds(10000));

daX.Duration = dr;

daY.Duration = dr;

this.tt.BeginAnimation(TranslateTransform.XProperty, daX);

//如果少了这条，则只是水平移动，没了y轴

this.tt.BeginAnimation(TranslateTransform.YProperty,daY);

}

3.关键帧动画

就是定几个位置，然后指定什么时间到这个点，什么时候到那个点就，程序就会自动在时间内均匀地到达，这样就不需要把几个动作协同了，很是方便

以下为按钮走z字形动画

private void button_Click(object sender, RoutedEventArgs e)

{

DoubleAnimationUsingKeyFrames daX = new DoubleAnimationUsingKeyFrames();

DoubleAnimationUsingKeyFrames daY = new DoubleAnimationUsingKeyFrames();

//总时间长

Duration dr = new Duration(TimeSpan.FromMilliseconds(10000));

daX.Duration = dr;

daY.Duration = dr;

//创建并添加X关键帧

LinearDoubleKeyFrame x_kf_1 = new LinearDoubleKeyFrame(200,KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(3000)));

LinearDoubleKeyFrame x_kf_2 = new LinearDoubleKeyFrame(0, KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(5000)));

LinearDoubleKeyFrame x_kf_3 = new LinearDoubleKeyFrame(200, KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(10000)));

daX.KeyFrames.Add(x_kf_1);

daX.KeyFrames.Add(x_kf_2);

daX.KeyFrames.Add(x_kf_3);

//创建并添加Y关键帧

LinearDoubleKeyFrame Y_kf_1 = new LinearDoubleKeyFrame(0, KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(3000)));

LinearDoubleKeyFrame Y_kf_2 = new LinearDoubleKeyFrame(180, KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(5000)));

LinearDoubleKeyFrame Y_kf_3 = new LinearDoubleKeyFrame(180, KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(10000)));

daY.KeyFrames.Add(Y_kf_1);

daY.KeyFrames.Add(Y_kf_2);

daY.KeyFrames.Add(Y_kf_3);

this.tt.BeginAnimation(TranslateTransform.XProperty, daX);

//如果少了这条，则只是水平移动，没了y轴

this.tt.BeginAnimation(TranslateTransform.YProperty,daY);

}

4.特殊关键帧动画

KeyFrames接收类型除了LinearDoubleKeyFrame(线性变化关键帧)，还有：

DiscreteDoubleKeyFrame：不连续变化关键帧

SplineDoubleKeyFrame：样条函数式变化关键帧，目标属性值的变化速率是一条贝赛尔贝线，常用

EasingDoubleKeyFrame:缓冲式变化关键帧

private void button_Click(object sender, RoutedEventArgs e)

{

DoubleAnimationUsingKeyFrames daX = new DoubleAnimationUsingKeyFrames();

DoubleAnimationUsingKeyFrames daY = new DoubleAnimationUsingKeyFrames();

//总时间长

Duration dr = new Duration(TimeSpan.FromMilliseconds(10000));

daX.Duration = dr;

daY.Duration = dr;

//创建并添加X关键帧

SplineDoubleKeyFrame kf = new SplineDoubleKeyFrame();

kf.KeyTime = KeyTime.FromPercent(1);

kf.Value = 400;

//贝赛尔曲线是由始点和终点，再加上两个控制点，控制点的坐标值就会造成直线的拉伸等变形形成的曲线

KeySpline ks = new KeySpline();

ks.ControlPoint1 = new Point(0, 1);

ks.ControlPoint2 = new Point(1, 0);

kf.KeySpline = ks;

daX.KeyFrames.Add(kf);

this.tt.BeginAnimation(TranslateTransform.XProperty, daX);

//如果少了这条，则只是水平移动，没了y轴

// this.tt.BeginAnimation(TranslateTransform.YProperty,daY);

}

最终结果是开始快，中间慢，后半部分又快

4.路径动画

绘制一条路径，然后让目标沿着一条给定的路径移动，使用DoubleAnimationUsingPath类。需要一个PathGeometry来指明移动的路径

<Window.Resources>

</Window.Resources>

private void button_Click(object sender, RoutedEventArgs e)

{

var pg = this.FindResource("movePath") as PathGeometry;

var du = new Duration(TimeSpan.FromMilliseconds(1000));

DoubleAnimationUsingPath daX = new DoubleAnimationUsingPath();

daX.PathGeometry = pg;

daX.Source = PathAnimationSource.X;（获取坐标值的X值）

daX.Duration = du;

var daY = new DoubleAnimationUsingPath();

daY.PathGeometry = pg;

daY.Source = PathAnimationSource.Y;（获取坐标值的X值）

daY.Duration = du;

this.tt.BeginAnimation(TranslateTransform.XProperty, daX);

this.tt.BeginAnimation(TranslateTransform.YProperty,daY);

}

//加上下面代码可永远运动

daX.AutoReverse = true;

daX.RepeatBehavior = RepeatBehavior.Forever;

daY.AutoReverse = true;

daY.RepeatBehavior = RepeatBehavior.Forever;

场景动画

场景动画就是多个元素组成一起的动画，一般是在xaml里写法，后台代码写很是复杂

<Grid>

<Ellipse.RenderTransform>

</Ellipse.RenderTransform>

</Ellipse>

</Border>

<Ellipse.RenderTransform>

</Ellipse.RenderTransform>

</Ellipse>

</Border>

<Ellipse.RenderTransform>

</Ellipse.RenderTransform>

</Ellipse>

</Border>

<Button.Triggers>

</DoubleAnimationUsingKeyFrames>

</DoubleAnimationUsingKeyFrames>

</Storyboard>

</BeginStoryboard>

</EventTrigger>

</Button.Triggers>

</Button>

</Grid>