导航试图控制器的代理

1，

#import <UIKit/UIKit.h>

@interface RootViewController : UIViewController <UINavigationControllerDelegate>

@end

2，代理实现的方法：

#pragma mark - Navigation Delegate

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated

{

    NSLog(@"willShowViewController : %@", viewController);

}

- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated

{

    NSLog(@"didShowViewController : %@", viewController);

}

3，设置代理

- (void)viewDidLoad

{

    [super viewDidLoad];

    // 设置UINavigtaion代理方法

    self.navigationController.delegate = self;

}