iOS渐隐渐现效果跳转

    ViewController *VC = [[ViewController alloc]init];

    CATransition *tration = [CATransition animation];

    tration.duration = 1.5f;

    transition.type = kCATransitionFade;

    [self.navigationController.view.layer addAnimation:tration forKey:nil]; 

    [self.navigationController pushViewController:VC animated:NO];