iOS-ナビゲーションコントローラシステムの戻るボタンのクリックpopと右スライドpopイベントをキャプチャする2つの方法(Demo付)

方法一：UIDIewControllerに分類を追加する（推奨使用、テスト済み）

#import 
@protocol BackButtonHandlerProtocol 
@optional
// Override this method in UIViewController derived class to handle 'Back' button click
- (BOOL)navigationShouldPopOnBackButton;
@end

@interface UIViewController (BackButtonHandler) 
@end

#import "UIViewController+BackButtonHandler.h"
#import 

@implementation UIViewController (BackButtonHandler)

@end

static NSString *const kOriginDelegate = @"kOriginDelegate";

@implementation UINavigationController (ShouldPopOnBackButton)

+ (void)load
{
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        Class class = [self class];
        
        SEL originSelector = @selector(viewDidLoad);
        SEL swizzledSelector = @selector(new_viewDidLoad);
        
        Method originMethod = class_getInstanceMethod(class, originSelector);
        Method swizzledMethod = class_getInstanceMethod(class, swizzledSelector);
        
        BOOL didAddMethod = class_addMethod(class,
                                            originSelector,
                                            method_getImplementation(swizzledMethod),
                                            method_getTypeEncoding(swizzledMethod));
        if (didAddMethod) {
            class_replaceMethod(class,
                                swizzledSelector,
                                method_getImplementation(originMethod),
                                method_getTypeEncoding(originMethod));
        } else {
            method_exchangeImplementations(originMethod, swizzledMethod);
        }
    });
}

- (void)new_viewDidLoad
{
    [self new_viewDidLoad];
    
    objc_setAssociatedObject(self, [kOriginDelegate UTF8String], self.interactivePopGestureRecognizer.delegate, OBJC_ASSOCIATION_ASSIGN);
    self.interactivePopGestureRecognizer.delegate = (id)self;
}

#pragma mark -  

- (BOOL)navigationBar:(UINavigationBar *)navigationBar shouldPopItem:(UINavigationItem *)item {
    
    if([self.viewControllers count] < [navigationBar.items count]) {
        return YES;
    }

    BOOL shouldPop = YES;
    UIViewController* vc = [self topViewController];
    if([vc respondsToSelector:@selector(navigationShouldPopOnBackButton)]) {
        shouldPop = [vc navigationShouldPopOnBackButton];
    }

    if(shouldPop) {
        dispatch_async(dispatch_get_main_queue(), ^{
            [self popViewControllerAnimated:YES];
        });
    } else {
        for(UIView *subview in [navigationBar subviews]) {
            if(0. < subview.alpha && subview.alpha < 1.) {
                [UIView animateWithDuration:.25 animations:^{
                    subview.alpha = 1.;
                }];
            }
        }
    }
    return NO;
}

#pragma mark -  

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
    if (gestureRecognizer == self.interactivePopGestureRecognizer) {
        UIViewController *vc = [self topViewController];
        if([vc respondsToSelector:@selector(navigationShouldPopOnBackButton)]) {
            return [vc navigationShouldPopOnBackButton];
        }
        id originDelegate = objc_getAssociatedObject(self, [kOriginDelegate UTF8String]);
        return [originDelegate gestureRecognizerShouldBegin:gestureRecognizer];
    }
    return YES;
}
@end

使用方法:

 pop 
#pragma mark- BackButtonHandlerProtocol
-(BOOL)navigationShouldPopOnBackButton{
     NSLog(@" 2");
    // 
    
    return YES;
}

方法2:UInavigationController追加プロトコルを継承する(使用を推奨しない)

#import 
@protocol LPNavigationControllerDelegate 
@optional
- (BOOL)controllerWillPopHandler;
@end

@interface LPNavigationController : UINavigationController
@end

#import "LPNavigationController.h"

@interface UINavigationController (UINavigationControllerNeedshouldPopItem)
- (BOOL)navigationBar:(UINavigationBar *)navigationBar shouldPopItem:(UINavigationItem *)item;
@end
@implementation UINavigationController(UINavigationControllerNeedshouldPopItem)

@end
//  Category UINavigationController navigationBar:shouldPopItem: ，
//  

@interface LPNavigationController ()
@end
@implementation LPNavigationController

- (BOOL)navigationBar:(UINavigationBar *)navigationBar shouldPopItem:(UINavigationItem *)item
{
    UIViewController *vc = self.topViewController;
    if ([vc respondsToSelector:@selector(controllerWillPopHandler)])
    {
        if ([vc performSelector:@selector(controllerWillPopHandler)])
        {
            return [super navigationBar:navigationBar shouldPopItem:item];
        }
        else
        {
            return NO;
        }
    }
    else
    {
        return [super navigationBar:navigationBar shouldPopItem:item];
    }
}
@end

使用方法:

 pop 
  
#pragma mark- LPNavigationControllerDelegate
-(BOOL)controllerWillPopHandler{
    
    NSLog(@" 1");
    // 
    
    return YES;
}

Demoダウンロード
参考文献:一:http://www.jianshu.com/p/a502d363c9982:http://www.jianshu.com/p/6376149a2c4c