代碼創建：

1、appdelegate 把contoller放到跟controller下

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
    
    self.window.rootViewController = [[MJOneViewController alloc] init];
    
    [self.window makeKeyAndVisible];
    return YES;
}

2、oneViewController跳轉的action

拿到要跳轉的控制器的，然後通過當前的controller 來 調用 presentViewController

- (IBAction)jump {
    // 展示MJTwoViewController
    MJTwoViewController *two = [[MJTwoViewController alloc] init];
    
    UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:two];
    
    [self presentViewController:nav animated:YES completion:^{
        NSLog(@"展示MJTwoViewController完畢.......");
    }];
}

3、twoController 返回之前的controller

調用 dismissViewController方法

- (IBAction)cancel {
//    NSLog(@"%@", self.view.window.rootViewController);
//    NSLog(@"%@", self.view.window.subviews);
    [self dismissViewControllerAnimated:YES completion:^{
        NSLog(@"關閉MJTwoViewController....");
    }];
//    [self.navigationController dismissViewControllerAnimated:YES completion:^{
//        NSLog(@"關閉MJTwoViewController....");
//    }];
}

在storyBoard創建modal控制器也很方便，直接ctrl 右擊 選在moadal模式