At least I got it (flashing effect)

So, here is the deal for creating a very simple animation that looks like a flashing effect.

theFlashView.alpha = 0.0f;

[[UIApplication sharedApplication].keyWindow addSubview:theFlashView];

[UIView beginAnimations:@"show" context:NULL];

[UIView setAnimationDuration:0.4f];

[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];

[UIView setAnimationDelegate:self];

theFlashView.alpha = 1.0f;

[UIView commitAnimations];

[UIView beginAnimations:@"show" context:NULL];

[UIView setAnimationDuration:0.4f];

[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];

[UIView setAnimationDelegate:self];

theFlashView.alpha = 0.0f;

[UIView commitAnimations];