导航栏removeGestureRecognizer未删除Guesture

Question

我需要在导航栏或视图上添加Tap Gesture。 我得到了以下解决方案，完全正常。

但是var taskTodoOnBar : UITapGestureRecognizer! override func viewWillAppear(animated: Bool) { navigationController?.view.addGestureRecognizer(taskTodoOnBar) } override func viewWillDisappear(animated: Bool) { navigationController?.view.removeGestureRecognizer(taskTodoOnBar) } 并没有删除手势，而是打破了其他视图控制器中其他后退按钮的功能。

如何解决问题？

override func viewWillAppear(animated: Bool)
{
    navigationController?.navigationBar.addGestureRecognizer(taskTodoOnBar)
}

override func viewWillDisappear(animated: Bool)
{
    navigationController?.navigationBar.removeGestureRecognizer(taskTodoOnBar)
}

或者

override func viewWillDisappear(animated: Bool)
{  
   print(navigationController!.view.gestureRecognizers!.count)
   print(navigationController!.navigationBar.gestureRecognizers!.count)
}

当我尝试获取gestureRecognizers时，它说没有。然后添加手势在哪里？

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Answer 1

尝试使用此

将手势声明为

let tapGesture : UITapGestureRecognizer = UITapGestureRecognizer()

手势处理程序

@objc func tapHandler(handler: UITapGestureRecognizer){
        print("gesture Added")
    }

在导航栏中添加

override func viewDidLoad()
    {
        super.viewDidLoad()
        tapGesture.numberOfTapsRequired = 1
        tapGesture.addTarget(self, action: #selector(VC2.tapHandler(handler:)))
        self.navigationController?.view.addGestureRecognizer(tapGesture)
    }

删除为

override func viewWillDisappear(_ animated: Bool) {
        for gesture in (navigationController?.view.gestureRecognizers)! {
            if gesture == tapGesture {
                navigationController?.view.removeGestureRecognizer(tapGesture)
                print("removed")
            }
        }
    }

更新了答案 - 手势计数打印为

控制台输出：

Answer 2

在iOS Geek的帮助下，我发现，在ViewdDidLoad中，gestureRecognizers！.count是2，但在viewWillDisappear中是nil。

然后我挖了更多，发现我已经为我的后退按钮编写了自定义代码。

所以在这种情况下，我们应该在popToViewController

之前删除GestureRecognizer

因此，对于我希望在使用自定义后退按钮时不会像我一样犯错的所有人。

func backBarBtnFnc(sender: UIBarButtonItem)
{
    navigationController?.navigationBar.removeGestureRecognizer(taskTodoOnBar)

    // CodTdo ...

    self.navigationController!.popToViewController(VC2, animated: true)
}