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

我想指出两点,这两点一直给我带来麻烦。

I was creating the Gesture Recognizer on init and storing it in a let property. Apparently, adding this gesture recog to the view does not work. May be self object passed to the gesture recognizer during init, is not properly configured. The gesture recognizer should not be added to views with zero frames. I create all my views with zero frame and then resize them using autolayout. The gesture recognizers have to be added AFTER the views have been resized by the autolayout engine. So I add the gesture recognizer in viewDidAppear and they work.

其他回答

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

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
}

如果你想要Objective - C代码,如下所示,

UITapGestureRecognizer *gesRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTap:)]; // Declare the Gesture.
gesRecognizer.delegate = self;
[yourView addGestureRecognizer:gesRecognizer]; // Add Gesture to your view.

// Declare the Gesture Recognizer handler method.

- (void)handleTap:(UITapGestureRecognizer *)gestureRecognizer{
   NSLog(@"Tapped");
}

或者你想要swift代码如下所示,

import UIKit
class ViewController: UIViewController {

    @IBOutlet weak var myView: UIView!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Add tap gesture recognizer to view
        let tapGesture = UITapGestureRecognizer(target: self, action: Selector("handleTap:"))
        myView.addGestureRecognizer(tapGesture)
    }

    // this method is called when a tap is recognized
    func handleTap(sender: UITapGestureRecognizer) {

        print("tap")
    }
}

xCode 9.3, Swift 4.0

class BaseVC: UIViewController, UIGestureRecognizerDelegate { 

      @IBOutlet weak var iView: UIView!

      override func viewDidLoad() {
          super.viewDidLoad()
          let clickUITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(self.onSelect(_:)))
          clickUITapGestureRecognizer.delegate = self
          iView?.addGestureRecognizer(tap)
      }

      func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
          return true
      }


     @IBAction func onSelect(_ sender: Any) {

     }
}

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!)
      }
    }