Swift4代码

尝试一些新的扩展方法:

import UIKit

extension UIView {

    fileprivate struct AssociatedObjectKeys {
        static var tapGestureRecognizer = "MediaViewerAssociatedObjectKey_mediaViewer"
    }

    fileprivate typealias Action = (() -> Void)?


    fileprivate var tapGestureRecognizerAction: Action? {
        set {
            if let newValue = newValue {
                // Computed properties get stored as associated objects
                objc_setAssociatedObject(self, &AssociatedObjectKeys.tapGestureRecognizer, newValue, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN)
            }
        }
        get {
            let tapGestureRecognizerActionInstance = objc_getAssociatedObject(self, &AssociatedObjectKeys.tapGestureRecognizer) as? Action
            return tapGestureRecognizerActionInstance
        }
    }


    public func addTapGestureRecognizer(action: (() -> Void)?) {
        self.isUserInteractionEnabled = true
        self.tapGestureRecognizerAction = action
        let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(handleTapGesture))
        self.addGestureRecognizer(tapGestureRecognizer)
    }


    @objc fileprivate func handleTapGesture(sender: UITapGestureRecognizer) {
        if let action = self.tapGestureRecognizerAction {
            action?()
        } else {
            print("no action")
        }
    }

}

现在，无论何时我们想要添加一个UITapGestureRecognizer到一个UIView或UIView的子类，如UIImageView，我们可以这样做，而不需要为选择器创建相关的函数!

用法:

 profile_ImageView.addTapGestureRecognizer {
        print("image tapped")
    }

斯威夫特这样做:

@IBOutlet weak var imageView: UIImageView!

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    let tap = UITapGestureRecognizer(target: self, action: #selector(ViewController.tappedMe))
    imageView.addGestureRecognizer(tap)
    imageView.isUserInteractionEnabled = true
}

func tappedMe() {
    print("Tapped on Image")
}

@IBOutlet weak var imageView: UIImageView!

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
//ViewController is your current view controller    
let tap = UITapGestureRecognizer(target: self, action: #selector(ViewController.tappedMe))
    imageView.addGestureRecognizer(tap)
    imageView.isUserInteractionEnabled = true
}

// Need to ass objective-c annotation 
@objc
func tappedMe() {
    print("Tapped on Image")
}

你可以添加一个UITapGestureRecognizer到imageView中，只需将一个拖到你的Storyboard/xib中，从imageView中按住ctrl拖动到gestureRecognizer中，再从gestureRecognizer中按住ctrl拖动到swift文件中，即可生成IBAction。

你还需要在UIImageView上启用用户交互，如下图所示:

这是我发现的，更容易设置。

这是YouTube上的视频

打开库，寻找“Tap Gesture Recognizer”对象。 将对象拖到故事板中，并将委托设置为您想要触发动作的图像。 然后转到视图控制器，拖动相同的对象设置IBAction。

你可以设置UIButton的图像到你通常会放在UIImageView中的图像。例如，你会这样做:

myImageView.image = myUIImage

你可以用:

myButton.setImage(myUIImage, forState: UIControlState.Normal)

下面是你的代码:

override func viewDidLoad(){
  super.viewDidLoad()

  var myUIImage: UIImage //set the UIImage here
  myButton.setImage(myUIImage, forState: UIControlState.Normal)
}

@IBOutlet var myButton: UIButton!
@IBAction func buttonTap(sender: UIButton!){
  //handle the image tap
}

使用这个方法的好处是，如果你必须从数据库中加载图像，你可以在设置图像之前设置按钮的标题:

myButton.setTitle("Loading Image...", forState: UIControlState.Normal)

告诉您的用户您正在加载图像