单击 UIBarButton 显示 toast 和双击返回动作需要执行

Question

我在导航栏中有一个 UIBarButton，当我点击后退按钮（第一次点击）时我需要显示吐司（如警告），双击我需要退出 swift 中的页面，

以下用于显示吐司的代码，它工作正常，

let toastLabel = UILabel(frame: CGRect(x: 20, y: self.view.frame.size.height-100, width: 350, height: 35))
    toastLabel.backgroundColor = UIColor.black.withAlphaComponent(0.6)
    toastLabel.textColor = UIColor.white
    toastLabel.textAlignment = .center;
    toastLabel.font = UIFont(name: "Montserrat-Light", size: 12.0)
    toastLabel.text = "demo"
    toastLabel.alpha = 1.0
    toastLabel.layer.cornerRadius = 10;
    toastLabel.clipsToBounds  =  true
    self.view.addSubview(toastLabel)
    UIView.animate(withDuration: 2.0, delay: 0.1, options: .curveEaseOut, animations: {
        toastLabel.alpha = 0.0
    }, completion: {(isCompleted) in
        toastLabel.removeFromSuperview()
    })

请指导我完成这个任务。

Answer 1

使用UIControlEventTouchDownRepeat事件，当tapCount为2时执行动作。

Answer 2

在UIButton上为控件事件UIControlEventTouchDownRepeat添加一个target-action，只在touch的tapCount为2时才做动作。如下Swift 3

button.addTarget(self, action: #selector(multipleTap(_:event:)), for: UIControlEvents.touchDownRepeat)

然后添加选择器如下

func multipleTap(_ sender: UIButton, event: UIEvent) {
    let touch: UITouch = event.allTouches!.first!
    if (touch.tapCount == 2) {
        // do action.
    }
}

Answer 3

override func viewDidLoad() {
        super.viewDidLoad()

        self.navigationItem.hidesBackButton = true
        let button = UIButton(type: .system)
        button.frame = CGRect(x: 0, y: 0, width: 80, height: 40)
        button.setTitle("Back", for: .normal)

        //Gesture Recognizer
        let singleTap = UITapGestureRecognizer(target: self, action: #selector(handleSingleTap))
        singleTap.numberOfTapsRequired = 1
        let doubleTap = UITapGestureRecognizer(target: self, action: #selector(handleDoubleTap))
        doubleTap.numberOfTapsRequired = 2
        button.addGestureRecognizer(singleTap)
        button.addGestureRecognizer(doubleTap)
        singleTap.require(toFail: doubleTap)

        let barButton = UIBarButtonItem(customView: button)
        self.navigationItem.leftBarButtonItem = barButton
    }
    @objc func handleSingleTap(sender: UITapGestureRecognizer? = nil) {
        let toastLabel = UILabel(frame: CGRect(x: 20, y: self.view.frame.size.height-100, width: 350, height: 35))
        toastLabel.backgroundColor = UIColor.black.withAlphaComponent(0.6)
        toastLabel.textColor = UIColor.white
        toastLabel.textAlignment = .center;
        toastLabel.font = UIFont(name: "Montserrat-Light", size: 12.0)
        toastLabel.text = "demo"
        toastLabel.alpha = 1.0
        toastLabel.layer.cornerRadius = 10;
        toastLabel.clipsToBounds  =  true
        self.view.addSubview(toastLabel)
        UIView.animate(withDuration: 2.0, delay: 0.1, options: .curveEaseOut, animations: {
            toastLabel.alpha = 0.0
        }, completion: {(isCompleted) in
            toastLabel.removeFromSuperview()
        })
        print("Single Tap detected")
    }
    @objc func handleDoubleTap(sender: UITapGestureRecognizer? = nil) {
        print("Double Tap detected")
    }

单击 UIBarButton 显示 toast 和双击返回动作需要执行

on single tap UIBarButton display toast and on double tap back action need to perform

navigationbar

ios

swift3