Easy [fade] animation for UIImageView.image

gistfile1.m

- (void)setSelected:(BOOL)selected animated:(BOOL)animated {
    selected_ = selected;

    if (animated) {
        CATransition *transition = [CATransition animation];
        transition.duration = 0.25f;
        transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
        transition.type = kCATransitionFade;
        [self.selectionImageView.layer addAnimation:transition forKey:nil];
    }
    
    self.selectionImageView.image = [UIImage imageNamed:selected ? @"radio-cell-selected" : @"radio-cell-deselected"];
}