Rotation - slowing it down using willAnimateSecondHalfOfRotationFromInterfaceOrientation

people, how do you actually slow down the orientation-rotation when using the "willAnimateSecondHalfOfRotationFr开发者_StackOverflow中文版omInterfaceOrientation:" method?

I currently have this:

-(void) willAnimateSecondHalfOfRotationFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation 
                                                       duration:(NSTimeInterval)duration {
    [self positionViews];
}

And I understand that this "willAnimate2ndHalf..." method gets called automatically when the rotation does indeed happen - well where do I actually get to change its DURATION value?

If you want to change the overall timing of he app's rotation, it can't be done. willAnimateSecondHalfOfRotationFromInterfaceOrientation is meant for adding custom code, like setting custom coordinates, properties, things like that.