Silverlight开发历程—关键帧动画

每一个关键帧都支持三种不同的补间类型,分别为 Linear(线性)、Discrete(离散)、Spliend(多键),如下图:


DoubleAnimationUsingKeyFrames动画

关键帧有两个重要的属性,分别是Value和KeyTime,他们的作用是在KeyTime指定的某个时间点对Value进行控制。如下例子:

<UserControl.Resources>
        <Storyboard x:Name="LinearStoryboard">
            <!--声明关键帧动画作用为TranslateTransform的 X属性-->
            <DoubleAnimationUsingKeyFrames BeginTime="0:0:0"  Storyboard.TargetName="ellipse1" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(TranslateTransform.X)">
                <!--线形补间-->
                <LinearDoubleKeyFrame Value="500" KeyTime="0:0:02" />
            </DoubleAnimationUsingKeyFrames>
        </Storyboard>
        <Storyboard x:Name="DiscreteStoryboard">
            <!--声明关键帧动画作用为TranslateTransform的 X属性-->
            <DoubleAnimationUsingKeyFrames BeginTime="0:0:0"  Storyboard.TargetName="ellipse2" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(TranslateTransform.X)">
                <!--离散补间-->
                <DiscreteDoubleKeyFrame Value="500" KeyTime="0:0:2.5"  />
            </DoubleAnimationUsingKeyFrames>
        </Storyboard>
        <Storyboard x:Name="SplineStoryboard">
            <!--声明关键帧动画作用为TranslateTransform的 X属性-->
            <DoubleAnimationUsingKeyFrames BeginTime="0:0:0"  Storyboard.TargetName="ellipse3" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(TranslateTransform.X)">
                <!--多键补间-->
                <SplineDoubleKeyFrame Value="500" KeyTime="0:0:4.5" KeySpline="0.6,0.0 0.9,0.0" />
            </DoubleAnimationUsingKeyFrames>
        </Storyboard>
    </UserControl.Resources>
    <Canvas x:Name="LayoutRoot" Background="White">
        <!--第一个圆-->
        <Ellipse x:Name="ellipse1" Width="70" Height="70" Canvas.Left="0" Canvas.Top="24">
            <Ellipse.Fill>
                <RadialGradientBrush Center="0.5,0.5">
                    <GradientStop Offset="0" Color="#FFECFFDB" />
                    <GradientStop Offset="1.0" Color="#FF252825" />
                    <GradientStop Offset="0.5" Color="#FF4D6D25" />
                </RadialGradientBrush>
            </Ellipse.Fill>
            <Ellipse.RenderTransform>
                <TransformGroup>
                    <TranslateTransform />
                </TransformGroup>
            </Ellipse.RenderTransform>
        </Ellipse>
        <!--第二个圆-->
        <Ellipse x:Name="ellipse2" Width="70" Height="70" Canvas.Left="1" Canvas.Top="118">
            <Ellipse.Fill>
                <RadialGradientBrush Center="0.5,0.5">
                    <GradientStop Offset="0" Color="#FFECFFDB" />
                    <GradientStop Offset="1.0" Color="#FF252825" />
                    <GradientStop Offset="0.5" Color="#FF4D6D25" />
                </RadialGradientBrush>
            </Ellipse.Fill>
            <Ellipse.RenderTransform>
                <TransformGroup>
                    <TranslateTransform />
                </TransformGroup>
            </Ellipse.RenderTransform>
        </Ellipse>
        <!--第三个圆-->
        <Ellipse x:Name="ellipse3" Width="70" Height="70" Canvas.Left="2" Canvas.Top="210">
            <Ellipse.Fill>
                <RadialGradientBrush Center="0.5,0.5">
                    <GradientStop Offset="0" Color="#FFECFFDB" />
                    <GradientStop Offset="1.0" Color="#FF252825" />
                    <GradientStop Offset="0.5" Color="#FF4D6D25" />
                </RadialGradientBrush>
            </Ellipse.Fill>
            <Ellipse.RenderTransform>
                <TransformGroup>
                    <TranslateTransform  />
                </TransformGroup>
            </Ellipse.RenderTransform>
        </Ellipse>
        <Button Canvas.Left="80" Canvas.Top="348" Content="播放" Height="23" Name="btn_player" Click="btn_player_Click"  Width="75" />
    </Canvas>
运行结果:

在上面的例子中用到了三种不同的帧补间类形,下图分别是三种不同类型补间的运动轨迹:

例子中分别使用了线性、离散、多键 三种不同的补间,很显然线性补间产生了一个最基本的水平运动,运动的过程速度是均匀的。离散补间直接从起始点跳 到了结束点,中间没有任何动画效果 。而多键补间是在由起始到结束的位置然后产生了一个加 速的动画。


ColorAnimationUsingKeyFrames 动画

ColorAnimationUsingKeyFrames关键帧是操作Color属性的变化,下面例子是对Color的值进行变化的:

<StackPanel Background="White" x:Name="myStackPanel"
            Loaded="Start_Animation">
    <StackPanel.Resources>
        <Storyboard x:Name="colorStoryboard">
            <ColorAnimationUsingKeyFrames BeginTime="00:00:00"
             Storyboard.TargetName="myStackPanel"
             Storyboard.TargetProperty="(Panel.Background).(SolidColorBrush.Color)">
                <LinearColorKeyFrame Value="Red" KeyTime="00:00:02" />
                <DiscreteColorKeyFrame Value="Yellow" KeyTime="00:00:2.5" />
                <SplineColorKeyFrame Value="Green" KeyTime="00:00:4.5" KeySpline="0.6,0.0 0.9,0.00" />

            </ColorAnimationUsingKeyFrames>
        </Storyboard>
    </StackPanel.Resources>
</StackPanel>
PointAnimationUsingKeyFrames动画
下面例子是控制EllipesGeometry的Center属性来让小球在三个点之间来回跳动。如下代码:

 <UserControl.Resources>
        <Storyboard x:Name="storyboard1"  AutoReverse="True" RepeatBehavior="Forever">
            <PointAnimationUsingKeyFrames  Storyboard.TargetName="ellipseGeometry1" Storyboard.TargetProperty="EllipseGeometry.Center" BeginTime="0:0:0">
                <LinearPointKeyFrame Value="75,93" KeyTime="0:0:0" ></LinearPointKeyFrame>
                <SplinePointKeyFrame Value="295,260" KeyTime="0:0:2" />
                <LinearPointKeyFrame Value="525,92" KeyTime="0:0:3" ></LinearPointKeyFrame>
            </PointAnimationUsingKeyFrames>
        </Storyboard>
    </UserControl.Resources>
    <Canvas x:Name="LayoutRoot" Background="White">
        <TextBlock Text="A" FontSize="40" FontFamily="Arial Black" Canvas.Left="58" Canvas.Top="22" Height="44" Width="32" />
        <TextBlock Text="B" FontSize="40" FontFamily="Arial Black" Canvas.Left="275" Canvas.Top="277" Height="44" Width="30" />
        <TextBlock Text="C" FontSize="40" FontFamily="Arial Black" Canvas.Left="499" Canvas.Top="22" Height="44" Width="32" />
        <Rectangle Width="75" Height="10" Fill="Green" Canvas.Left="39" Canvas.Top="64"></Rectangle>
        <Rectangle Width="75" Height="10" Fill="Green" Canvas.Left="255" Canvas.Top="277"></Rectangle>
        <Rectangle Width="75" Height="10" Fill="Green" Canvas.Left="482" Canvas.Top="64"></Rectangle>
        <!--第一个圆-->

        <Path>
            <Path.Data>
                <EllipseGeometry x:Name="ellipseGeometry1" Center="75,93" RadiusX="20" RadiusY="20">
                </EllipseGeometry>
            </Path.Data>
            <Path.Fill>
                <RadialGradientBrush Center="0.5,0.5">
                    <GradientStop Offset="0" Color="#FFECFFDB" />
                    <GradientStop Offset="1.0" Color="#FF252825" />
                    <GradientStop Offset="0.5" Color="#FF4D6D25" />
                </RadialGradientBrush>
            </Path.Fill>
        </Path>
        <Button Canvas.Left="255" Canvas.Top="348" Content="运动" Height="23" Name="btn_Run" Click="btn_Run_Click" Width="75" />
    </Canvas>

运行结果:


原文地址:https://www.cnblogs.com/raphael5200/p/5114875.html