Custom animation for modal dismiss

UIViewController.m

- (void)dismiss
{
    [CATransaction begin];
    
    CATransition *transition = [CATransition animation];
    transition.type = kCATransitionReveal;
    transition.subtype = kCATransitionFromTop;
    transition.duration = 0.25f;
    transition.fillMode = kCAFillModeForwards;
    transition.removedOnCompletion = YES;
    
    [[UIApplication sharedApplication].keyWindow.layer addAnimation:transition forKey:@"transition"];
    [[UIApplication sharedApplication] beginIgnoringInteractionEvents];
    [CATransaction setCompletionBlock: ^ {
        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(transition.duration * NSEC_PER_SEC)), dispatch_get_main_queue(), ^ {
            [[UIApplication sharedApplication] endIgnoringInteractionEvents];
        });
    }];
    
    [self dismissViewControllerAnimated:NO completion:nil];
    
    [CATransaction commit];
}