runtime实现全屏pop手势

自定义 NavigationController 继承于系统 UINavigationController

导入头文件 #import <objc/runtime.h>

NavigationController 中实现如下方法

// OBJC
- (void)viewDidLoad {
    [super viewDidLoad];
     
     // 取出系统pop手势的`target`和`action`
     NSArray *targetObjs = [self.interactivePopGestureRecognizer valueForKey:@"_targets"];
     id target = [targetObjs.firstObject valueForKey:@"target"];
     SEL sel = NSSelectorFromString(@"handleNavigationTransition:");
      
     UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:target action:sel];
     [self.view addGestureRecognizer:panGesture];
  
}

// swift
override func viewDidLoad() {
    super.viewDidLoad()
  
    // 获取系统pop手势的target和action
    guard let targets = interactivePopGestureRecognizer?.value(forKey: "_targets") as? [NSObject] else { return }
    let targetObj = targets.first
    let target = targetObj?.value(forKey: "target")
    let action = Selector(("handleNavigationTransition:"))
  
    let panGesture = UIPanGestureRecognizer(target: target, action: action)
    view.addGestureRecognizer(panGesture)
  
}

runtime的使用

- OBJC
      unsigned int outCount = 0;
      Ivar *ivars = class_copyIvarList([UIGestureRecognizer class], &outCount);
      
      unsigned int outCountMethod = 0;
      Method *methods = class_copyMethodList([UIGestureRecognizer class], &outCountMethod);
      
      for (unsigned int i = 0; i < outCount; i++) {
          Ivar ivar = ivars[i];
          NSString *key = [NSString stringWithUTF8String:ivar_getName(ivar)];
          NSLog(@"%@", key);
      }

      NSLog(@"==========");

      for (unsigned int i = 0; i < outCountMethod; i++) {
          Method method = methods[i];
          SEL sel = method_getName(method);
          NSString *selName = NSStringFromSelector(sel);
          NSLog(@"%@", selName);
      }

- swift
      // 获取 UIGestureRecognizer 的属性列表
      var count: UInt32 = 0
      let ivars = class_copyIvarList(UIGestureRecognizer.self, &count)!
      for i in 0..<count {
          let nameP = ivar_getName(ivars[Int(i)])!
          let name = String(cString: nameP)
          print(name)
      }