自定义全屏返回手势

电玩女神 2022-05-29 00:20 286阅读 0赞

> 代码地址如下：  
> [http://www.demodashi.com/demo/11971.html][http_www.demodashi.com_demo_11971.html]
> 
> 使用分类，入侵性低，直接拖动到项目中，一句代码都不用写，自动生效

## 演示效果 ##

![RirEcar85u8tQgktUFj.gif][]

## 目录结构 ##

![UMEWfpJ2T7bfMSP9B9R.jpg][]

## 原理 ##

**.h文件**

/// 自定义全屏拖拽返回手势
    @property (nonatomic, strong, readonly) UIPanGestureRecognizer *popGestureRecognizer;

定义单个控制器取消手势方法

- (void)cancleHMFullScreenPopGesRec:(BOOL)cancle;

**.m文件**

一、引入头文件`#import <objc/runtime.h>`

二、定义手势代理类

// 判断是否是根控制器，如果是，取消手势
        if (self.navigationController.viewControllers.count <= 1) {
            return NO;
        }
    
        // 如果正在转场动画，取消手势
        if ([[self.navigationController valueForKey:@"_isTransitioning"] boolValue]) {
            return NO;
        }
    
        // 判断手指移动方向
        CGPoint translation = [gestureRecognizer translationInView:gestureRecognizer.view];
        if (translation.x <= 0) {
            return NO;
        }
        if (self.isCancle) {
            return NO;
        }
        return YES;
    }

三、在NCPopGestureRecognizer的类实现中

在load方法中交换navVC的push方法和自定义的方法实例

+ (void)load {
    
        Method originalMethod = class_getInstanceMethod([self class], @selector(pushViewController:animated:));
        Method swizzledMethod = class_getInstanceMethod([self class], @selector(hm_pushViewController:animated:));
    
        method_exchangeImplementations(originalMethod, swizzledMethod);
    }

取消的方法调用上边自定义类的属性赋值

- (void)cancleHMFullScreenPopGesRec:(BOOL)cancle {
    
        [self hm_fullScreenPopGestureRecognizerDelegate].isCancle = cancle;
    
    }

自定义push方法和手势  
根据kvc取值拿到 target 和action添加到自定义手势  
并禁用系统交换手势，设置手势代理为自定义类

- (void)hm_pushViewController:(UIViewController *)viewController animated:(BOOL)animated {
    
        if (![self.interactivePopGestureRecognizer.view.gestureRecognizers containsObject:self.popGestureRecognizer]) {
            [self.interactivePopGestureRecognizer.view addGestureRecognizer:self.popGestureRecognizer];
    
            NSArray *targets = [self.interactivePopGestureRecognizer valueForKey:@"targets"];
            id internalTarget = [targets.firstObject valueForKey:@"target"];
            SEL internalAction = NSSelectorFromString(@"handleNavigationTransition:");
    
            self.popGestureRecognizer.delegate = [self hm_fullScreenPopGestureRecognizerDelegate];
            [self.popGestureRecognizer addTarget:internalTarget action:internalAction];
    
            // 禁用系统的交互手势
            self.interactivePopGestureRecognizer.enabled = NO;
        }
    
        if (![self.viewControllers containsObject:viewController]) {
            [self hm_pushViewController:viewController animated:animated];
        }
    }

用runtime给分类添加属性绑定

“\`objc  
\- (HMFullScreenPopGestureRecognizerDelegate \*)hm\_fullScreenPopGestureRecognizerDelegate \{  
HMFullScreenPopGestureRecognizerDelegate \*delegate = objc\_getAssociatedObject(self, \_cmd);  
if (!delegate) \{  
delegate = \[\[HMFullScreenPopGestureRecognizerDelegate alloc\] init\];  
delegate.navigationController = self;

objc_setAssociatedObject(self, _cmd, delegate, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    }
    return delegate;

\}  
\- (UIPanGestureRecognizer \*)popGestureRecognizer \{  
UIPanGestureRecognizer \*panGestureRecognizer = objc\_getAssociatedObject(self, \_cmd);

if (panGestureRecognizer == nil) {
        panGestureRecognizer = [[UIPanGestureRecognizer alloc] init];
        panGestureRecognizer.maximumNumberOfTouches = 1;
    
        objc_setAssociatedObject(self, _cmd, panGestureRecognizer, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    }
    return panGestureRecognizer;

\}  
“\`自定义全屏返回手势

> 代码地址如下：  
> [http://www.demodashi.com/demo/11971.html][http_www.demodashi.com_demo_11971.html]
> 
> 注：本文著作权归作者，由demo大师发表，拒绝转载，转载需要作者授权

[http_www.demodashi.com_demo_11971.html]: http://www.demodashi.com/demo/11971.html
[RirEcar85u8tQgktUFj.gif]: /images/20220529/3a2107eac052431c950b861c1a6db537.png
[UMEWfpJ2T7bfMSP9B9R.jpg]: /images/20220529/9666486a42f24e8b875c15414f6715bb.png