Как управлять временем анимации Key-Frame

В этом примере показано, как управлять временем ключевых кадров в анимации ключевых кадров. Как и другие анимации, анимации с ключевым кадром имеют свойство Duration. Помимо указания длительности анимации, необходимо указать, какая часть этой длительности выделена каждому из его ключевых кадров. Чтобы выделить время, необходимо указать KeyTime для каждого ключевого кадра в анимации.

KeyTime для каждого ключевого кадра указывает, когда заканчивается ключевой кадр (он не указывает продолжительность воспроизведения ключевых кадров). Можно указать KeyTime как значение TimeSpan, в процентах или как специальное значение Uniform или Paced.

Пример

В следующем примере используется DoubleAnimationUsingKeyFrames для анимации прямоугольника на экране. Ключевые моменты ключевых кадров задаются с помощью значений TimeSpan.

/*
   This Rectangle is animated with KeyTimes using TimeSpan Values.
   It moves horizontally to 100 in the first 3 seconds, 100 to 300 in
   the next second, and 300 to 500 in the last 6 seconds.
*/

// Create the a rectangle.
Rectangle aRectangle = new Rectangle();
aRectangle.Fill = Brushes.Blue;
aRectangle.Stroke = Brushes.Black;
aRectangle.StrokeThickness = 5;
aRectangle.Width = 50;
aRectangle.Height = 50;

// Create a transform to move the rectangle
// across the screen.
TranslateTransform translateTransform1 =
    new TranslateTransform();
aRectangle.RenderTransform = translateTransform1;

// Create a DoubleAnimationUsingKeyFrames
// to animate the transform.
DoubleAnimationUsingKeyFrames transformAnimation =
    new DoubleAnimationUsingKeyFrames();
transformAnimation.Duration = TimeSpan.FromSeconds(10);

// Animate to 100 at 3 seconds.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(100, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(3))));

// Animate to 300 at 4 seconds.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(300, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(4))));

// Animate to 500 at 10 seconds.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(500, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(10))));

// Start the animation when the rectangle is loaded.
aRectangle.Loaded += delegate(object sender, RoutedEventArgs e)
{
    translateTransform1.BeginAnimation(TranslateTransform.XProperty, transformAnimation);
};

'            
'               This Rectangle is animated with KeyTimes using TimeSpan Values. 
'               It moves horizontally to 100 in the first 3 seconds, 100 to 300 in 
'               the next second, and 300 to 500 in the last 6 seconds.
'            

            ' Create the a rectangle.
            Dim aRectangle As New Rectangle()
            aRectangle.Fill = Brushes.Blue
            aRectangle.Stroke = Brushes.Black
            aRectangle.StrokeThickness = 5
            aRectangle.Width = 50
            aRectangle.Height = 50

            ' Create a transform to move the rectangle
            ' across the screen.
            Dim translateTransform1 As New TranslateTransform()
            aRectangle.RenderTransform = translateTransform1

            ' Create a DoubleAnimationUsingKeyFrames
            ' to animate the transform.
            Dim transformAnimation As New DoubleAnimationUsingKeyFrames()
            transformAnimation.Duration = TimeSpan.FromSeconds(10)

            ' Animate to 100 at 3 seconds.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(100, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(3))))

            ' Animate to 300 at 4 seconds.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(300, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(4))))

            ' Animate to 500 at 10 seconds.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(500, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(10))))

            ' Start the animation when the rectangle is loaded.
            AddHandler aRectangle.Loaded, Sub(sender As Object, e As RoutedEventArgs) translateTransform1.BeginAnimation(TranslateTransform.XProperty, transformAnimation)

<!-- This Rectangle is animated with KeyTimes using TimeSpan Values. 
     It moves horizontally to 100 in the first 3 seconds, 100 to 300 in 
     the next second, and 300 to 500 in the last 6 seconds. -->
<Rectangle Fill="Blue" Stroke="Black" StrokeThickness="5"
  Width="50" Height="50">
  <Rectangle.RenderTransform>
    <TranslateTransform x:Name="TranslateTransform1" />
  </Rectangle.RenderTransform>
  <Rectangle.Triggers>
    <EventTrigger RoutedEvent="Rectangle.Loaded">
      <BeginStoryboard>
        <Storyboard>
          <DoubleAnimationUsingKeyFrames 
            Storyboard.TargetName="TranslateTransform1" 
            Storyboard.TargetProperty="X"
            Duration="0:0:10">

            <!-- These KeyTime properties are specified as TimeSpan values 
                 which are in the form of "hours:minutes:seconds". -->
            <LinearDoubleKeyFrame Value="100" KeyTime="0:0:3" />
            <LinearDoubleKeyFrame Value="300" KeyTime="0:0:4" />
            <LinearDoubleKeyFrame Value="500" KeyTime="0:0:10" />
          </DoubleAnimationUsingKeyFrames>
        </Storyboard>
      </BeginStoryboard>
    </EventTrigger>
  </Rectangle.Triggers>
</Rectangle>

На следующем рисунке показано, когда достигается значение каждого ключевого кадра.

В следующем примере показана анимация, которая идентична, за исключением того, что ключевые времена ключевых кадров установлены в процентных значениях.

/*
  This rectangle moves horizontally to 100 in the first 3 seconds,
  100 to 300 in  the next second, and 300 to 500 in the last 6 seconds.
*/

// Create the a rectangle.
Rectangle aRectangle = new Rectangle();
aRectangle.Fill = Brushes.Purple;
aRectangle.Stroke = Brushes.Black;
aRectangle.StrokeThickness = 5;
aRectangle.Width = 50;
aRectangle.Height = 50;

// Create a transform to move the rectangle
// across the screen.
TranslateTransform translateTransform2 =
    new TranslateTransform();
aRectangle.RenderTransform = translateTransform2;

// Create a DoubleAnimationUsingKeyFrames
// to animate the transform.
DoubleAnimationUsingKeyFrames transformAnimation =
    new DoubleAnimationUsingKeyFrames();
transformAnimation.Duration = TimeSpan.FromSeconds(10);

// Animate to 100 at 30% of the animation's duration.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(100, KeyTime.FromPercent(0.3)));

// Animate to 300 at 40% of the animation's duration.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(300, KeyTime.FromPercent(0.4)));

// Animate to 500 at 100% of the animation's duration.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(500, KeyTime.FromPercent(1.0)));

// Start the animation when the rectangle is loaded.
aRectangle.Loaded += delegate(object sender, RoutedEventArgs e)
{
    translateTransform2.BeginAnimation(TranslateTransform.XProperty, transformAnimation);
};

'            
'              This rectangle moves horizontally to 100 in the first 3 seconds, 
'              100 to 300 in  the next second, and 300 to 500 in the last 6 seconds.
'            

            ' Create the a rectangle.
            Dim aRectangle As New Rectangle()
            aRectangle.Fill = Brushes.Purple
            aRectangle.Stroke = Brushes.Black
            aRectangle.StrokeThickness = 5
            aRectangle.Width = 50
            aRectangle.Height = 50

            ' Create a transform to move the rectangle
            ' across the screen.
            Dim translateTransform2 As New TranslateTransform()
            aRectangle.RenderTransform = translateTransform2

            ' Create a DoubleAnimationUsingKeyFrames
            ' to animate the transform.
            Dim transformAnimation As New DoubleAnimationUsingKeyFrames()
            transformAnimation.Duration = TimeSpan.FromSeconds(10)

            ' Animate to 100 at 30% of the animation's duration.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(100, KeyTime.FromPercent(0.3)))

            ' Animate to 300 at 40% of the animation's duration.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(300, KeyTime.FromPercent(0.4)))

            ' Animate to 500 at 100% of the animation's duration.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(500, KeyTime.FromPercent(1.0)))

            ' Start the animation when the rectangle is loaded.
            AddHandler aRectangle.Loaded, Sub(sender As Object, e As RoutedEventArgs) translateTransform2.BeginAnimation(TranslateTransform.XProperty, transformAnimation)

<!-- This rectangle moves horizontally to 100 in the first 3 seconds, 
     100 to 300 in  the next second, and 300 to 500 in the last 6 seconds.-->
<Rectangle Fill="Purple" Stroke="Black" StrokeThickness="5"
  Width="50" Height="50">
  <Rectangle.RenderTransform>
    <TranslateTransform x:Name="TranslateTransform2" />
  </Rectangle.RenderTransform>
  <Rectangle.Triggers>
    <EventTrigger RoutedEvent="Rectangle.Loaded">
      <BeginStoryboard>
        <Storyboard>
          <DoubleAnimationUsingKeyFrames 
            Storyboard.TargetName="TranslateTransform2" 
            Storyboard.TargetProperty="X"
            Duration="0:0:10">

            <!-- KeyTime properties are expressed as Percentages. -->
            <LinearDoubleKeyFrame Value="100" KeyTime="30%" />
            <LinearDoubleKeyFrame Value="300" KeyTime="40%" />
            <LinearDoubleKeyFrame Value="500" KeyTime="100%" />
          </DoubleAnimationUsingKeyFrames>
        </Storyboard>
      </BeginStoryboard>
    </EventTrigger>
  </Rectangle.Triggers>
</Rectangle>

На следующем рисунке показано, когда достигается значение каждого ключевого кадра.

В следующем примере используются ключевые значения времени Uniform.

/*
   This rectangle is animated with KeyTimes using Uniform values.
   Goes to 100 in the first 3.3 seconds, 100 to
   300 in the next 3.3 seconds, 300 to 500 in the last 3.3 seconds.
*/

// Create the a rectangle.
Rectangle aRectangle = new Rectangle();
aRectangle.Fill = Brushes.Red;
aRectangle.Stroke = Brushes.Black;
aRectangle.StrokeThickness = 5;
aRectangle.Width = 50;
aRectangle.Height = 50;

// Create a transform to move the rectangle
// across the screen.
TranslateTransform translateTransform3 =
    new TranslateTransform();
aRectangle.RenderTransform = translateTransform3;

// Create a DoubleAnimationUsingKeyFrames
// to animate the transform.
DoubleAnimationUsingKeyFrames transformAnimation =
    new DoubleAnimationUsingKeyFrames();
transformAnimation.Duration = TimeSpan.FromSeconds(10);

/*
   KeyTime properties are expressed with values of Uniform. When a key time is set to
   "Uniform" the total allotted time of the animation is divided evenly between key frames.
   In this example, the total duration of the animation is ten seconds and there are four
   key frames each of which are set to "Uniform", therefore, the duration of each key frame
   is 3.3 seconds (10/3).
 */

// Animate to 100.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(100, KeyTime.Uniform));

// Animate to 300.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(300, KeyTime.Uniform));

// Animate to 500.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(500, KeyTime.Uniform));

// Start the animation when the rectangle is loaded.
aRectangle.Loaded += delegate(object sender, RoutedEventArgs e)
{
    translateTransform3.BeginAnimation(TranslateTransform.XProperty, transformAnimation);
};

'            
'               This rectangle is animated with KeyTimes using Uniform values. 
'               Goes to 100 in the first 3.3 seconds, 100 to
'               300 in the next 3.3 seconds, 300 to 500 in the last 3.3 seconds.
'            

            ' Create the a rectangle.
            Dim aRectangle As New Rectangle()
            aRectangle.Fill = Brushes.Red
            aRectangle.Stroke = Brushes.Black
            aRectangle.StrokeThickness = 5
            aRectangle.Width = 50
            aRectangle.Height = 50

            ' Create a transform to move the rectangle
            ' across the screen.
            Dim translateTransform3 As New TranslateTransform()
            aRectangle.RenderTransform = translateTransform3

            ' Create a DoubleAnimationUsingKeyFrames
            ' to animate the transform.
            Dim transformAnimation As New DoubleAnimationUsingKeyFrames()
            transformAnimation.Duration = TimeSpan.FromSeconds(10)

'            
'               KeyTime properties are expressed with values of Uniform. When a key time is set to
'               "Uniform" the total allotted time of the animation is divided evenly between key frames.  
'               In this example, the total duration of the animation is ten seconds and there are four 
'               key frames each of which are set to "Uniform", therefore, the duration of each key frame 
'               is 3.3 seconds (10/3).
'             

            ' Animate to 100.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(100, KeyTime.Uniform))

            ' Animate to 300.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(300, KeyTime.Uniform))

            ' Animate to 500.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(500, KeyTime.Uniform))

            ' Start the animation when the rectangle is loaded.
            AddHandler aRectangle.Loaded, Sub(sender As Object, e As RoutedEventArgs) translateTransform3.BeginAnimation(TranslateTransform.XProperty, transformAnimation)

<!-- This rectangle is animated with KeyTimes using Uniform values. 
     Goes to 100 in the first 3.3 seconds, 100 to
     300 in the next 3.3 seconds, 300 to 500 in the last 3.3 seconds. -->
<Rectangle Fill="Red" Stroke="Black" StrokeThickness="5"
  Width="50" Height="50">
  <Rectangle.RenderTransform>
    <TranslateTransform x:Name="TranslateTransform3" />
  </Rectangle.RenderTransform>
  <Rectangle.Triggers>
    <EventTrigger RoutedEvent="Rectangle.Loaded">
      <BeginStoryboard>
        <Storyboard>
          <DoubleAnimationUsingKeyFrames 
            Storyboard.TargetName="TranslateTransform3" 
            Storyboard.TargetProperty="X"
            Duration="0:0:10">

            <!--   KeyTime properties are expressed with values of Uniform. When a key time is set to
                   "Uniform" the total allotted time of the animation is divided evenly between key frames.  
                   In this example, the total duration of the animation is ten seconds and there are four 
                   key frames each of which are set to "Uniform", therefore, the duration of each key frame 
                   is 3.3 seconds (10/3). -->
            <LinearDoubleKeyFrame Value="100" KeyTime="Uniform" />
            <LinearDoubleKeyFrame Value="300" KeyTime="Uniform" />
            <LinearDoubleKeyFrame Value="500" KeyTime="Uniform" />
          </DoubleAnimationUsingKeyFrames>
        </Storyboard>
      </BeginStoryboard>
    </EventTrigger>
  </Rectangle.Triggers>
</Rectangle>

На следующем рисунке показано, когда достигается значение каждого ключевого кадра.

В последнем примере используются значения времени ключей Paced.

/*
   This rectangle is animated with KeyTimes using Paced Values.
   The rectangle moves between key frames at uniform rate except for first key frame
   because using a Paced value on the first KeyFrame in a collection of frames gives a time of zero.
*/

// Create the a rectangle.
Rectangle aRectangle = new Rectangle();
aRectangle.Fill = Brushes.Orange;
aRectangle.Stroke = Brushes.Black;
aRectangle.StrokeThickness = 5;
aRectangle.Width = 50;
aRectangle.Height = 50;

// Create a transform to move the rectangle
// across the screen.
TranslateTransform translateTransform4 =
    new TranslateTransform();
aRectangle.RenderTransform = translateTransform4;

// Create a DoubleAnimationUsingKeyFrames
// to animate the transform.
DoubleAnimationUsingKeyFrames transformAnimation =
    new DoubleAnimationUsingKeyFrames();
transformAnimation.Duration = TimeSpan.FromSeconds(10);

/*
   Use Paced values when a constant rate is desired.
   The time allocated to a key frame with a KeyTime of "Paced" is
   determined by the time allocated to the other key frames of the animation. This time is
   calculated to attempt to give a "paced" or "constant velocity" for the animation.
 */

// Animate to 100.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(100, KeyTime.Paced));

// Animate to 300.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(300, KeyTime.Paced));

// Animate to 500.
transformAnimation.KeyFrames.Add(
    new LinearDoubleKeyFrame(500, KeyTime.Paced));

// Start the animation when the rectangle is loaded.
aRectangle.Loaded += delegate(object sender, RoutedEventArgs e)
{
    translateTransform4.BeginAnimation(TranslateTransform.XProperty, transformAnimation);
};

'            
'               This rectangle is animated with KeyTimes using Paced Values. 
'               The rectangle moves between key frames at uniform rate except for first key frame
'               because using a Paced value on the first KeyFrame in a collection of frames gives a time of zero.
'            

            ' Create the a rectangle.
            Dim aRectangle As New Rectangle()
            aRectangle.Fill = Brushes.Orange
            aRectangle.Stroke = Brushes.Black
            aRectangle.StrokeThickness = 5
            aRectangle.Width = 50
            aRectangle.Height = 50

            ' Create a transform to move the rectangle
            ' across the screen.
            Dim translateTransform4 As New TranslateTransform()
            aRectangle.RenderTransform = translateTransform4

            ' Create a DoubleAnimationUsingKeyFrames
            ' to animate the transform.
            Dim transformAnimation As New DoubleAnimationUsingKeyFrames()
            transformAnimation.Duration = TimeSpan.FromSeconds(10)

'            
'               Use Paced values when a constant rate is desired. 
'               The time allocated to a key frame with a KeyTime of "Paced" is
'               determined by the time allocated to the other key frames of the animation. This time is 
'               calculated to attempt to give a "paced" or "constant velocity" for the animation.
'             

            ' Animate to 100.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(100, KeyTime.Paced))

            ' Animate to 300.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(300, KeyTime.Paced))

            ' Animate to 500.
            transformAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(500, KeyTime.Paced))

            ' Start the animation when the rectangle is loaded.
            AddHandler aRectangle.Loaded, Sub(sender As Object, e As RoutedEventArgs) translateTransform4.BeginAnimation(TranslateTransform.XProperty, transformAnimation)

<!-- This rectangle is animated with KeyTimes using Paced Values. 
     The rectangle moves between key frames at uniform rate except for first key frame
     because using a Paced value on the first KeyFrame in a collection of frames gives a time of zero. -->
<Rectangle Fill="Orange" Stroke="Black" StrokeThickness="5"
  Width="50" Height="50">
  <Rectangle.RenderTransform>
    <TranslateTransform x:Name="TranslateTransform4" />
  </Rectangle.RenderTransform>
  <Rectangle.Triggers>
    <EventTrigger RoutedEvent="Rectangle.Loaded">
      <BeginStoryboard>
        <Storyboard>
          <DoubleAnimationUsingKeyFrames 
            Storyboard.TargetName="TranslateTransform4" 
            Storyboard.TargetProperty="X"
            Duration="0:0:10">

            <!-- Use Paced values when a constant rate is desired. 
                 The time allocated to a key frame with a KeyTime of "Paced" is
                 determined by the time allocated to the other key frames of the animation. This time is 
                 calculated to attempt to give a "paced" or "constant velocity" for the animation. -->
            <LinearDoubleKeyFrame Value="100" KeyTime="Paced" />
            <LinearDoubleKeyFrame Value="300" KeyTime="Paced" />
            <LinearDoubleKeyFrame Value="500" KeyTime="Paced" />
          </DoubleAnimationUsingKeyFrames>
        </Storyboard>
      </BeginStoryboard>
    </EventTrigger>
  </Rectangle.Triggers>
</Rectangle>

На следующем рисунке показано, когда достигается значение каждого ключевого кадра.

Для простоты в версиях кода этого примера используются локальные анимации, а не раскадровки, так как применяется только одна анимация к одному свойству, но примеры могут быть изменены для использования раскадровки. Пример объявления сториборда в коде см. в разделе Анимация свойства с помощью сториборда.

Полный пример можно посмотреть в примере анимации ключевых кадров . Дополнительные сведения об анимации ключевых кадров см. в разделе Key-Frame Обзор анимации.

См. также

• Обзор анимаций Key-Frame
• Обзор анимации
• Темы по инструкции