Namespace:
System.Windows.Media.Animation
Assembly:
PresentationCore (in PresentationCore.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
Visual Basic (Declaration)
Public Event CurrentStateInvalidated As EventHandler
Dim instance As Timeline
Dim handler As EventHandler
AddHandler instance.CurrentStateInvalidated, handler
public event EventHandler CurrentStateInvalidated
public:
event EventHandler^ CurrentStateInvalidated {
void add (EventHandler^ value);
void remove (EventHandler^ value);
}
JScript does not support events.
<object CurrentStateInvalidated="EventHandler" .../>
Use the CurrentStateInvalidated event when you want to be notified when a timeline's Clock starts, stops, or fills.
Pausing a Clock does not change its CurrentState. To be notified when a clock becomes paused, use the CurrentGlobalSpeedInvalidated event.
Although this event occurs when the ClockState becomes invalid, that doesn't necessarily mean the ClockState changed: a Clock that switches from Active to Filling and then back to Active in the same tick will cause this event to fire, but its CurrentState property won't actually change.
The Object parameter of the EventHandler event handler is the Clock that was created for this timeline.
Although this event handler appears to be associated with a timeline, it actually registers with the Clock created for this timeline. For more information, see the Timing Events Overview.
A clock's CurrentStateInvalidated event occurs when its CurrentState becomes invalid, such as when the clock starts or stops. You can register for this event with directly using a Clock, or you can register using a Timeline.
In the following example, a Storyboard and two DoubleAnimation objects are used to animate the width of two rectangles. The CurrentStateInvalidated event is used to listen for clock state changes.
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
x:Class="Microsoft.Samples.Animation.TimingBehaviors.StateExample"
Background="LightGray">
<StackPanel Margin="20">
<TextBlock
Name="ParentTimelineStateTextBlock"></TextBlock>
<TextBlock
Name="Animation1StateTextBlock"></TextBlock>
<Rectangle
Name="Rectangle01"
Width="100" Height="50" Fill="Orange" />
<TextBlock Name="Animation2StateTextBlock"></TextBlock>
<Rectangle
Name="Rectangle02"
Width="100" Height="50" Fill="Gray" />
<Button Content="Start Animations" Margin="20">
<Button.Triggers>
<EventTrigger RoutedEvent="Button.Click">
<BeginStoryboard>
<Storyboard RepeatBehavior="2x" AutoReverse="True"
CurrentStateInvalidated="parentTimelineStateInvalidated" >
<DoubleAnimation
Storyboard.TargetName="Rectangle01"
Storyboard.TargetProperty="Width"
From="10" To="200" Duration="0:0:9"
BeginTime="0:0:1"
CurrentStateInvalidated="animation1StateInvalidated"/>
<DoubleAnimation
Storyboard.TargetName="Rectangle02"
Storyboard.TargetProperty="Width"
From="10" To="200" Duration="0:0:8"
BeginTime="0:0:1"
CurrentStateInvalidated="animation2StateInvalidated" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Button.Triggers>
</Button>
</StackPanel>
</Page>
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
namespace Microsoft.Samples.Animation.TimingBehaviors
{
public partial class StateExample : Page
{
private void parentTimelineStateInvalidated(object sender, EventArgs args)
{
Clock myClock = (Clock)sender;
ParentTimelineStateTextBlock.Text +=
myClock.CurrentTime.ToString() + ":"
+ myClock.CurrentState.ToString() + " ";
}
private void animation1StateInvalidated(object sender, EventArgs args)
{
Clock myClock = (Clock)sender;
Animation1StateTextBlock.Text +=
myClock.Parent.CurrentTime.ToString() + ":"
+ myClock.CurrentState.ToString() + " ";
}
private void animation2StateInvalidated(object sender, EventArgs args)
{
Clock myClock = (Clock)sender;
Animation2StateTextBlock.Text +=
myClock.Parent.CurrentTime.ToString() + ":"
+ myClock.CurrentState.ToString() + " ";
}
}
}
The following illustration shows the different states the animations enter as the parent timeline (Storyboard) progresses.
.png)
The following table shows the times at which Animation1's CurrentStateInvalidated event fires:
Time (Seconds)
|
1
|
10
|
19
|
21
|
30
|
39
|
State
|
Active
|
Active
|
Stopped
|
Active
|
Active
|
Stopped
|
The following table shows the times at which Animation2's CurrentStateInvalidated event fires:
Time (Seconds)
|
1
|
9
|
11
|
19
|
21
|
29
|
31
|
39
|
State
|
Active
|
Filling
|
Active
|
Stopped
|
Active
|
Filling
|
Active
|
Stopped
|
Notice that Animation1's CurrentStateInvalidated event fires at 10 seconds, even though its state remains Active. That's because its state changed at 10 seconds, but it changed from Active to Filling and then back to Active in the same tick.
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0
Reference
CurrentStateInvalidated