导航栏pop拦截

一、新建一个分类

二、导入分类头文件

三、需要拦截的地方实现方法   - (BOOL)navigationShouldPopTwo  即可

.h

#import <UIKit/UIKit.h>

@protocol BackButtonHandlerProtocol <NSObject>
@optional

- (BOOL)navigationShouldPopTwo;
@end

@interface UIViewController (BackButtonHandler) <BackButtonHandlerProtocol>

@end

.m

#import "UIViewController+BackButtonHandler.h"

@implementation UIViewController (BackButtonHandler)

@end

@implementation UINavigationController (ShouldPopOnBackButton)

//当控制器的Item需要pop的时候执行下面的方法（不管是手动返回，侧滑返回，代码pop都会调用下面方法）
//返回YES，释放Item；返回NO，不释放当前Item
- (BOOL)navigationBar:(UINavigationBar *)navigationBar shouldPopItem:(UINavigationItem *)item {

    NSLog(@"pop kzhiq:%ld items:%ld",self.viewControllers.count,navigationBar.items.count);
    //控制器数小于Item数时，必须直接pop 掉 item
    if([self.viewControllers count] < [navigationBar.items count]) {
        return YES;
    }
    BOOL shouldPop = YES;
    UIViewController* vc = [self topViewController];
    if ([vc respondsToSelector:@selector(navigationShouldPopTwo)]) {

        shouldPop = ![vc navigationShouldPopTwo];//这个方法里面执行了其他的pop操作

    }
    if(shouldPop) {//
        dispatch_async(dispatch_get_main_queue(), ^{
            [self popViewControllerAnimated:YES];//没有外部操作时，直接代码pop,这时
        });
    }

    return NO;
}
@end