Timeline.CurrentGlobalSpeedInvalidated Event
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Occurs when the rate at which time progresses for the timeline's clock changes.
public:
event EventHandler ^ CurrentGlobalSpeedInvalidated;public event EventHandler CurrentGlobalSpeedInvalidated;member this.CurrentGlobalSpeedInvalidated : EventHandler Public Custom Event CurrentGlobalSpeedInvalidated As EventHandler Event Type
Examples
The following example shows how to register for the CurrentGlobalSpeedInvalidated event.
/*
This example shows how to register for the
CurrentGlobalSpeedInvalidated event
using a Timeline.
*/
using System;
using System.Windows;
using System.Windows.Navigation;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Controls;
using System.Windows.Input;
namespace Microsoft.Samples.Animation.TimingBehaviors
{
public class TimelineCurrentGlobalSpeedInvalidatedExample : Page {
private TextBlock currentTimeTextBlock;
public TimelineCurrentGlobalSpeedInvalidatedExample()
{
// Create a name scope.
NameScope.SetNameScope(this, new NameScope());
WindowTitle = "GetAnimationBaseValue Example";
StackPanel myPanel = new StackPanel();
myPanel.Margin = new Thickness(20);
// Create a rectangle.
Rectangle animatedRectangle = new Rectangle();
animatedRectangle.Width = 100;
animatedRectangle.Height = 50;
animatedRectangle.Margin = new Thickness(50);
animatedRectangle.Fill = Brushes.Orange;
animatedRectangle.Stroke = Brushes.Gray;
animatedRectangle.StrokeThickness = 2;
// Create a RotateTransform.
RotateTransform animatedTransform = new RotateTransform();
animatedTransform.Angle = 0;
this.RegisterName("animatedTransform", animatedTransform);
animatedRectangle.RenderTransform = animatedTransform;
animatedRectangle.RenderTransformOrigin = new Point(0.5,0.5);
myPanel.Children.Add(animatedRectangle);
this.Content = myPanel;
// Create a TextBlock to show the storyboard's current time.
currentTimeTextBlock = new TextBlock();
myPanel.Children.Add(currentTimeTextBlock);
// Animate the RotateTransform's angle using a Storyboard.
DoubleAnimation angleAnimation = new DoubleAnimation(0,360, TimeSpan.FromSeconds(5));
angleAnimation.RepeatBehavior = RepeatBehavior.Forever;
angleAnimation.AutoReverse = true;
Storyboard.SetTargetName(angleAnimation, "animatedTransform");
Storyboard.SetTargetProperty(angleAnimation,
new PropertyPath(RotateTransform.AngleProperty));
Storyboard theStoryboard = new Storyboard();
theStoryboard.Children.Add(angleAnimation);
// Register the CurrentGlobalSpeedInvalidated event.
// You must register for events before you begin
// the storyboard.
angleAnimation.CurrentGlobalSpeedInvalidated +=
new EventHandler(angleAnimation_CurrentGlobalSpeedInvalidated);
// Start the storyboard.
theStoryboard.Begin(animatedRectangle, true);
}
private void angleAnimation_CurrentGlobalSpeedInvalidated(object sender, EventArgs e)
{
// Sender is the clock that was created for the DoubleAnimation.
Clock doubleAnimationClock = (Clock)sender;
// Update the TextBlock with the time of its parent.
currentTimeTextBlock.Text = doubleAnimationClock.Parent.CurrentTime.ToString();
}
}
}
'
'
' This example shows how to register for the
' CurrentGlobalSpeedInvalidated event
' using a Timeline.
'
'
Imports System.Windows
Imports System.Windows.Navigation
Imports System.Windows.Media
Imports System.Windows.Media.Animation
Imports System.Windows.Shapes
Imports System.Windows.Controls
Imports System.Windows.Input
Namespace Microsoft.Samples.Animation.TimingBehaviors
Public Class TimelineCurrentGlobalSpeedInvalidatedExample
Inherits Page
Private currentTimeTextBlock As TextBlock
Public Sub New()
' Create a name scope.
NameScope.SetNameScope(Me, New NameScope())
WindowTitle = "GetAnimationBaseValue Example"
Dim myPanel As New StackPanel()
myPanel.Margin = New Thickness(20)
' Create a rectangle.
Dim animatedRectangle As New Rectangle()
With animatedRectangle
.Width = 100
.Height = 50
.Margin = New Thickness(50)
.Fill = Brushes.Orange
.Stroke = Brushes.Gray
.StrokeThickness = 2
End With
' Create a RotateTransform.
Dim animatedTransform As New RotateTransform()
animatedTransform.Angle = 0
Me.RegisterName("animatedTransform", animatedTransform)
animatedRectangle.RenderTransform = animatedTransform
animatedRectangle.RenderTransformOrigin = New Point(0.5, 0.5)
myPanel.Children.Add(animatedRectangle)
Me.Content = myPanel
' Create a TextBlock to show the storyboard's current time.
currentTimeTextBlock = New TextBlock()
myPanel.Children.Add(currentTimeTextBlock)
' Animate the RotateTransform's angle using a Storyboard.
Dim angleAnimation As New DoubleAnimation(0, 360, TimeSpan.FromSeconds(5))
angleAnimation.RepeatBehavior = RepeatBehavior.Forever
angleAnimation.AutoReverse = True
Storyboard.SetTargetName(angleAnimation, "animatedTransform")
Storyboard.SetTargetProperty(angleAnimation, New PropertyPath(RotateTransform.AngleProperty))
Dim theStoryboard As New Storyboard()
theStoryboard.Children.Add(angleAnimation)
' Register the CurrentGlobalSpeedInvalidated event.
' You must register for events before you begin
' the storyboard.
AddHandler angleAnimation.CurrentGlobalSpeedInvalidated, AddressOf angleAnimation_CurrentGlobalSpeedInvalidated
' Start the storyboard.
theStoryboard.Begin(animatedRectangle, True)
End Sub
Private Sub angleAnimation_CurrentGlobalSpeedInvalidated(ByVal sender As Object, ByVal e As EventArgs)
' Sender is the clock that was created for the DoubleAnimation.
Dim doubleAnimationClock As Clock = CType(sender, Clock)
' Update the TextBlock with the time of its parent.
currentTimeTextBlock.Text = doubleAnimationClock.Parent.CurrentTime.ToString()
End Sub
End Class
End Namespace
Remarks
The current global speed of a timeline's clock changes in the following circumstances:
The clock changes direction because of its timeline's AutoReverse setting.
The clock accelerates or decelerates because of its timeline's AccelerationRatio or DecelerationRatio property settings.
The clock is paused or resumed.
The clock becomes inactive or reactivates.
The CurrentGlobalSpeed of one of the clock's parent changes.
The CurrentGlobalSpeedInvalidated event is useful for tracking when a timeline's clock becomes paused; in your event handler, use your storyboard's GetCurrentGlobalSpeed method or check the clock's IsPaused property to determine whether its clock is paused; compare this against a previously cached value to determine whether it changed.
The Object parameter of the EventHandler event handler is the timeline's Clock.
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.
Applies to
See also
Collaborate with us on GitHub
The source for this content can be found on GitHub, where you can also create and review issues and pull requests. For more information, see our contributor guide.
