swift用闭包去处理UIButton(按钮)/UIImageV

我们ui搭建中经常要为UIButton或UIImageVIew添加点击的事件。而点击事件要放在另一个方法上处理，看着就很不爽，所以就想用闭包方式处理了。使用如下：

        view.addSubview(button)
        button.addAction { (button) in
            print("click button")
        }
        
        view.addSubview(button2)
        button2.addAction {[weak self]  (button) in
            guard let ws = self else {return}//防止使用self循环引用
            print("click button2")
        }
        
        view.addSubview(imageView)
        imageView.addAction { (imageView) in
            print("click imageView")
        }


        emailField.textChangeAction { (field) in
            print("textChange")
        }

具体的扩展代码如下：

fileprivate typealias buttonClick = ((UIButton)->())
extension UIButton {
    
    @objc private func clickAction() {
        self.actionBlock?(self)
    }
    
    private struct RuntimeKey {
        static let actionBlock = UnsafeRawPointer.init(bitPattern: "actionBlock".hashValue)
    }
    private var actionBlock: buttonClick? {
        set {
            objc_setAssociatedObject(self, UIButton.RuntimeKey.actionBlock!, newValue, .OBJC_ASSOCIATION_COPY_NONATOMIC)
        }
        get {
            return  objc_getAssociatedObject(self, UIButton.RuntimeKey.actionBlock!) as? buttonClick
        }
    }

    
    func addAction(controlEvents: UIControl.Event = .touchUpInside ,handle:@escaping ((UIButton)->())) {
        self.actionBlock = handle
        self.addTarget(self, action: #selector(clickAction), for: controlEvents)
    }
    
}


fileprivate typealias imageClick = ((UIImageView)->())
extension UIImageView {
    
    @objc private func clickAction() {
        self.actionBlock?(self)
    }
    
    private struct RuntimeKey {
        static let actionBlock = UnsafeRawPointer.init(bitPattern: "actionBlock".hashValue)
    }
    private var actionBlock: imageClick? {
        set {
            objc_setAssociatedObject(self, UIImageView.RuntimeKey.actionBlock!, newValue, .OBJC_ASSOCIATION_COPY_NONATOMIC)
        }
        get {
            return  objc_getAssociatedObject(self, UIImageView.RuntimeKey.actionBlock!) as? imageClick
        }
    }
    
    
    func addAction(handle:@escaping ((UIImageView)->())) {
        self.actionBlock = handle
        self.isUserInteractionEnabled = true
        let tap = UITapGestureRecognizer(target: self, action: #selector(clickAction))
        self.addGestureRecognizer(tap)
    }
    
}


fileprivate typealias TextFieldChange = ((UITextField)->())
extension UITextField {
    
    @objc private func changeAction() {
        self.actionBlock?(self)
    }
    
    private struct RuntimeKey {
        static let actionBlock = UnsafeRawPointer.init(bitPattern: "actionBlock".hashValue)
    }
    private var actionBlock: TextFieldChange? {
        set {
            objc_setAssociatedObject(self, UITextField.RuntimeKey.actionBlock!, newValue, .OBJC_ASSOCIATION_COPY_NONATOMIC)
        }
        get {
            return  objc_getAssociatedObject(self, UITextField.RuntimeKey.actionBlock!) as? TextFieldChange
        }
    }
    
    
    func textChangeAction(handle:@escaping ((UITextField)->())) {
        self.actionBlock = handle
        self.addTarget(self, action: #selector(changeAction), for: UIControl.Event.editingChanged)
    }
    
}

完