我有一个UIView并且我添加了点击手势

let tap = UITapGestureRecognizer(target: self, action: Selector("handleTap:"))
tap.delegate = self
myView.addGesture(tap)

我试图在testfile中以编程方式调用它。

sendActionForEvent

我正在使用这个函数,但它不起作用:

myView.sendActionForEvent(UIEvents.touchUpDown)

它显示未识别的选择器发送到实例。

我该如何解决这个问题呢?


当前回答

对于Swift 4:

let tap = UITapGestureRecognizer(target: self, action: #selector(self.handleTap(_:)))

view.addGestureRecognizer(tap)

view.isUserInteractionEnabled = true

self.view.addSubview(view)

// function which is triggered when handleTap is called
@objc func handleTap(_ sender: UITapGestureRecognizer) {
    print("Hello World")
}

在Swift 4中,你需要显式地指出触发的函数是可从Objective-C调用的,所以你需要添加@objc你的handleTap函数。

请看@Ali Beadle的回答:Swift 4添加手势:覆盖vs @objc

其他回答

我使用的是Xcode 7.3.1, Swift 2.2。见下文。

func addTapGesture() {
    let tap = UITapGestureRecognizer(target: self, action: #selector(MyViewController.handleTap))
    tap.numberOfTapsRequired = 1
    self.myView.addGestureRecognizer(tap)
}

func handleTap() {
    // Your code here...
}

我是在swift上的Xcode 6.4上完成的。见下文。

var view1: UIView!

func assignTapToView1() {          
  let tap = UITapGestureRecognizer(target: self, action: Selector("handleTap"))
  //  tap.delegate = self
  view1.addGestureRecognizer(tap)
  self.view .addSubview(view1)

...
}

func handleTap() {
 print("tap working")
 view1.removeFromSuperview()
 // view1.alpha = 0.1
}

试试下面的swift代码(在Xcode 6.3.1中测试):

    import UIKit

    class KEUITapGesture150427 : UIViewController {
      var _myTap: UITapGestureRecognizer?
      var _myView: UIView?

      override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = UIColor.whiteColor();

        _myTap = UITapGestureRecognizer(target: self
, action: Selector("_myHandleTap:"))
        _myTap!.numberOfTapsRequired = 1

        _myView = UIView(frame: CGRectMake(100, 200, 100, 100))
        _myView!.backgroundColor=UIColor.blueColor()
        _myView!.layer.cornerRadius = 20
        _myView!.layer.borderWidth = 1
        _myView!.addGestureRecognizer(_myTap!)
        view.addSubview(_myView!)
      }

      func _myHandleTap(sender: UITapGestureRecognizer) {
        if sender.state == .Ended {
          println("_myHandleTap(sender.state == .Ended)")
          sender.view!.backgroundColor
          = UIColor(red: CGFloat(drand48()), green: CGFloat(drand48()), blue: CGFloat(drand48()), alpha: 1.0);
        }
      }
    }

注意,你的目标可以是UIResponder的任何子类,参见(在Xcode 6.3.1中测试):

    import UIKit

    class MyTapTarget  : UIResponder {
      func _myHandleTap2(sender: UITapGestureRecognizer) {
        if sender.state == .Ended {
          println("_myHandleTap2(sender.state == .Ended)")
          sender.view!.backgroundColor
            = UIColor(red: CGFloat(drand48()), green: CGFloat(drand48()), blue: CGFloat(drand48()), alpha: 1.0);
        }
      }
    }

    class KEUITapGesture150427b : UIViewController {
      var _myTap: UITapGestureRecognizer?
      var _myView: UIView?
      var _myTapTarget: MyTapTarget?

      override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = UIColor.whiteColor();

        _myTapTarget = MyTapTarget()
        _myTap = UITapGestureRecognizer(target: _myTapTarget!
, action: Selector("_myHandleTap2:"))
        _myTap!.numberOfTapsRequired = 1

        _myView = UIView(frame: CGRectMake(100, 200, 100, 100))
        _myView!.backgroundColor=UIColor.blueColor()
        _myView!.layer.cornerRadius = 20
        _myView!.layer.borderWidth = 1
        _myView!.addGestureRecognizer(_myTap!)
        view.addSubview(_myView!)
      }
    }

你需要用目标和动作初始化UITapGestureRecognizer,如下所示:

let tap = UITapGestureRecognizer(target: self, action: #selector(self.handleTap(_:)))
myView.addGestureRecognizer(tap)

然后,你应该实现处理程序,它将在每次tap事件发生时被调用:

@objc func handleTap(_ sender: UITapGestureRecognizer? = nil) {
    // handling code
}

所以现在调用你的点击手势识别器事件处理程序就像调用一个方法一样简单:

handleTap()

斯威夫特4

let tap = UITapGestureRecognizer(target: self, action: #selector(self.touchTapped(_:)))
    self.view.addGestureRecognizer(tap)

@objc func touchTapped(_ sender: UITapGestureRecognizer) {
}