1:了解，当创建一个UINavigationcontroller中时，当创建一个子视图控制器压入uiNavigationController中，其中里面的view也别加入UINavigationcontoller.view中去了

验证代码

-(void)viewWillDisappear:(BOOL)animated{    [super viewWillDisappear:animated];      [self digui:self.navigationController.view];     NSLog(@"2.1-->%p",self.view.superview);}-(void)digui:(UIView *)view{    for (UIView *child in view.subviews) {        NSLog(@"---%p",child);        [self digui:child];    }    }

 

转场动画第一种方式

-(void)click{        MyViewController *my=[[MyViewController alloc] init];    [self.navigationController pushViewController:my animated:NO];     //因为一个事件循环机制中    CATransition *tran=[CATransition animation];    tran.duration=0.75;    tran.type=@"cameraIrisHollowOpen";    tran.subtype=kCATransitionFromLeft;    [self.navigationController.view.layer addAnimation:tran forKey:nil];}

转场动画第二种方式

-(void)click{            [UIView transitionWithView:self.navigationController.view duration:0.5 options:UIViewAnimationOptionTransitionCurlUp animations:^{        MyViewController *my=[[MyViewController alloc] init];        [self.navigationController pushViewController:my animated:NO];    } completion:^(BOOL finished) {            }];      }

转场动画第三种方式

-(void)click{    [UIView beginAnimations:nil context:nil];    [UIView setAnimationDuration:0.5];    [UIView setAnimationTransition:UIViewAnimationTransitionCurlUp forView:self.navigationController.view  cache:YES];    MyViewController *my=[[MyViewController alloc] init];   [self.navigationController pushViewController:my animated:NO];    [UIView commitAnimations];    }