glowing effect of view disables button in it - iphone

Question

I have uiscrollview with some buttons in it. I want to make one particular button to glow.
I made glowing-pulsating effect of button with following code:
(button in UIView)
- (IBAction)selectChampionAction:(id)sender{
if ( self.timer ) {
// Stop timer
[self.timer invalidate];
self.timer = nil;
// Workaround: we have to return the layer's delegate property to what it was
// Otherwise, we will encounter an unexpected result
self.viewForGlowing.layer.delegate = self.viewForGlowing;
} else {
// Woraround: UIView's layer property does not support animation by default
// assigning nil to layer's delegate property enables the animation somehow.
self.viewForGlowing.layer.delegate = nil;
// Start timer
self.timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:#selector(timerExpired:) userInfo:nil repeats:YES];
[self.timer fire];
}
}
- (void) timerExpired:(NSTimer *) timer
{
if ( self.viewForGlowing.layer.shadowRadius == 20 ) {
// Increase
[CATransaction begin];
[CATransaction setValue:[NSNumber numberWithFloat:1.0f] forKey:kCATransactionAnimationDuration];
self.viewForGlowing.layer.shadowRadius = 30;
self.viewForGlowing.layer.shadowOpacity = 1;
[CATransaction commit];
} else {
// Decrease
[CATransaction begin];
[CATransaction setValue:[NSNumber numberWithFloat:1.0f] forKey:kCATransactionAnimationDuration];
self.viewForGlowing.layer.shadowRadius = 20;
self.viewForGlowing.layer.shadowOpacity = 0.7;
[CATransaction commit];
}
}
But when i press other buttons glowing button stops response.
I suppose that this happens because of this line of code
self.viewForGlowing.layer.delegate = nil;
My Questions:
Are there other approaches to make UIButton glow?
How to make button response after other buttons pressed?