C# 4 and .NET 4

animations ❘ 1021
Duration="0:0:3" AutoReverse="True"
FillBehavior="Stop"
RepeatBehavior="Forever"
AccelerationRatio="0.9" DecelerationRatio="0.1"
From="100" To="300" />
Figures 35-29 and 35-30 show two states from the animated ellipse.
code snippet AnimationDemo/EllipseWindow.xaml
Animations are far more than typical window-dressing animation that appears onscreen
constantly and immediately. You can add animation to business applications that make the
user interface more responsive.
The following example demonstrates a decent animation and also
shows how the animation can be defined in a style. Within the Window
resources you can see the style AnimatedButtonStyle for buttons. In
the template, a rectangle-named outline is defined. This template has
a thin stroke with the thickness set to 0.4.
figure 35-30
The template defines a property trigger for the IsMouseOver property. The
EnterActions property of this trigger applies as soon as the mouse is moved over
the button. The action to start is BeginStoryboard. BeginStoryboard is a trigger
action that can contain and thus start Storyboard elements. The Storyboard
element defines a DoubleAnimation to animate a double value. The property
value that is changed in this animation is the Rectangle.StrokeThickness of the
Rectangle element with the name outline. The value is changed in a smooth way
by 1.2, as the By property specifies, for a time length of 0.3 seconds as specified by
the Duration property. At the end of the animation, the stroke thickness is reset
to its original value because AutoReverse=“True“. To summarize: as soon as the
mouse moves over the button, the thickness of the outline is incremented by 1.2 for
0.3 seconds. Figure 35-31 shows the button without animation, and Figure 35-32
shows the button 0.3 seconds after the mouse moved over it. (It’s just not possible
to show the smooth animation and intermediate looks in a print medium.)
figure 35-31
figure 35-32
figure 35-29
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