代码之家 › 专栏 › 技术社区 › Cheok Yan Cheng

为什么当点击区域落在按钮上时,UIGestureRecognizerDelegate的shouldRecognizeSimultaneouslyWith没有执行?

swift ios

Cheok Yan Cheng · 技术社区 · 5 年前

我想

检测屏幕上任何位置的全局触摸事件
不会影响按钮和下面的自定义视图等组件。下面的按钮、自定义视图仍然能够接收点击事件。

我所做的是

UITapGestureRecognizer 在里面 UIApplication.shared.keyWindow
UIGestureRecognizerDelegate ,返回 true 对于 shouldRecognizeSimultaneouslyWith

这是我的密码

import UIKit

extension UIWindow {
    static var key: UIWindow! {
        if #available(iOS 13, *) {
            return UIApplication.shared.windows.first { $0.isKeyWindow }
        } else {
            return UIApplication.shared.keyWindow
        }
    }
}

extension ViewController: UIGestureRecognizerDelegate {
    func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer,
           shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer)
            -> Bool {
        print(">>> shouldRecognizeSimultaneouslyWith returns true")
        return true
    }
}

class ViewController: UIViewController {
    // Lazy is required as self is not ready yet without lazy.
    private lazy var globalGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(globalTapped))
    
    private func installGlobalGestureRecognizer() {
        UIWindow.key.removeGestureRecognizer(globalGestureRecognizer)
        UIWindow.key.addGestureRecognizer(globalGestureRecognizer)
        
        globalGestureRecognizer.delegate = self
    }

    @objc func globalTapped() {
        print(">>> global tapped")
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }

    @IBAction func buttonClicked(_ sender: Any) {
        print("yellow button tap\n")
    }
    
    @IBAction func handleTap(_ gesture: UITapGestureRecognizer) {
        print("red view tap\n")
    }
    
    @IBAction func installButtonClicked(_ sender: Any) {
        print("install global gesture")
        installGlobalGestureRecognizer()
    }
}

这是点击红色自定义视图时发生的情况

install global gesture
>>> shouldRecognizeSimultaneouslyWith returns true
>>> shouldRecognizeSimultaneouslyWith returns true
>>> global tapped
red view tap

点击黄色按钮时(全局手势不工作)

install global gesture
yellow button tap

这是我为自定义红色视图和黄色按钮安装tap事件处理程序的方式。

有人知道为什么吗点击按钮时是否未调用?我希望在点击黄色按钮时

应同时识别 已执行并返回true
已执行全局手势点击事件处理程序

谢谢

0 回复 | 直到 5 年前

Phil Dukhov 5 年前

正如@DonMag正确地说的那样,这种情况的发生是因为按钮触摸没有被处理 UIGestureRecognizer s

UIControl 直接从 UIWindow UIApplication

使用 UI窗口 SceneDelegate

class CustomWindow: UIWindow {
    override func sendEvent(_ event: UIEvent) {
        super.sendEvent(event)
        print(#function, event)
    }
}

class SceneDelegate: UIResponder, UIWindowSceneDelegate {
    var window: UIWindow?

    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        guard let scene = (scene as? UIWindowScene) else { return }
        window = CustomWindow(windowScene: scene)
        window?.rootViewController = UIStoryboard(name: "Main", bundle: nil).instantiateInitialViewController()
    }
}

我更喜欢使用 UIApplication应用程序

UIApplication子类

class CustomUIApplication: UIApplication {
    override func sendEvent(_ event: UIEvent) {
        super.sendEvent(event)
        print(#function, event)
    }
}

去除 @main 注释自 AppDelegate
main.swift 包括以下内容:

UIApplicationMain(
    CommandLine.argc,
    CommandLine.unsafeArgv,

    NSStringFromClass(CustomUIApplication.self),
    NSStringFromClass(AppDelegate.self)
)

Wide Angle Technology 5 年前

Nadeem Taj 5 年前

原因是在 viewDidLoad() 您的 ViewController 视图控制器 .

为了更好地理解 enter link description here