CATransactions not working

FROM : Adam Radestock
DATE : Sun May 18 18:00:36 2008

Hi everyone,

I've been struggling to work out how to animate some properties on my 
NSButton subclass. I have looked through all the examples given in 
Apple's docs, but can't work out why my code doesn't animate.

My code is:
   [CATransaction begin]; // Begin grouping animated property changes
   
   if (highlightEffect == SGUIButtonOpaqueEffect) {
       
       [CATransaction begin];
       [CATransaction setValue:[NSNumber numberWithFloat:5.0f]
                        forKey:kCATransactionAnimationDuration];
       self.layer.opacity = 1.0;
       [CATransaction commit];
       
   } else if (highlightEffect == SGUIButtonSlideEffect) {
       
       [CATransaction begin];
       [CATransaction setValue:[NSNumber numberWithFloat:1.0f]
                        forKey:kCATransactionAnimationDuration];
       self.layer.bounds = CGRectMake(self.layer.position.x, 
self.layer.position.y, self.bounds.size.width + 10, 
self.bounds.size.height);
       [CATransaction commit];
       
       [CATransaction begin];
       [CATransaction setValue:[NSNumber numberWithFloat:2.0f]
                        forKey:kCATransactionAnimationDuration];
       self.layer.position = CGPointMake(self.layer.position.x - 
self.layer.bounds.size.width, self.layer.position.y);
       [CATransaction commit];
       
   }
   
   [CATransaction commit];

Can anyone see any problems with this? Why aren't there any animations 
when this code executes?

Any help greatly appreciated.

Adam Radestock
Glass Monkey Software