You might use a second animation with an appropriate BeginTime
:
var switchOffAnimation = new DoubleAnimation
{
To = 0,
Duration = TimeSpan.Zero
};
var switchOnAnimation = new DoubleAnimation
{
To = 1,
Duration = TimeSpan.Zero,
BeginTime = TimeSpan.FromSeconds(0.5)
};
var blinkStoryboard = new Storyboard
{
Duration = TimeSpan.FromSeconds(1),
RepeatBehavior = RepeatBehavior.Forever
};
Storyboard.SetTarget(switchOffAnimation, MyCanvas);
Storyboard.SetTargetProperty(switchOffAnimation, new PropertyPath(Canvas.OpacityProperty));
blinkStoryboard.Children.Add(switchOffAnimation);
Storyboard.SetTarget(switchOnAnimation, MyCanvas);
Storyboard.SetTargetProperty(switchOnAnimation, new PropertyPath(Canvas.OpacityProperty));
blinkStoryboard.Children.Add(switchOnAnimation);
MyCanvas.BeginStoryboard(blinkStoryboard);