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wyk19910103 2016-07-28 15:10 原文

最近在学习Swift ,发现青玉伏案大神早期用OC写的一篇博客-- IOS开发之自定义Button(集成三种回调模式) 很适合用来熟悉Swift的回调方式，于是我就用Swift翻版了一下，具体实现原理就不多说了，主要贴上Swift的代码给大家看看。由于刚开始了解Swift，有使用不恰当的地方请轻拍。。。。 

上代码：

1、新建一个xib，拖一个UIView到界面上，绑定上自定义的UIView类，拖一个UILabel到view上，写上Button假装是个UIButton；并将label拖到代码当中

2、我这里回调三种Button点击事件，TouchDown、TouchUpInside、TouchUpOutside

A、首先是Target：

a、首先声明一个枚举来设定点击类型

enum MyControlEvents{
    case TouchUpInside
    case TouchUpOutside
    case TouchDown
}

b、设置Target、action和Event三个属性

//声明三个属性、添加一个addTarget方法，注意Target和delegate一样要用weak修饰
    weak var target:AnyObject?
    var action:Selector?
    var controlEvents:MyControlEvents?
    
    func addTarget(target:AnyObject!, action: Selector!, forMyControlEvents controlEvents: MyControlEvents! ){
        self.target = target
        self.action = action
        self.controlEvents = controlEvents
    }

c、在touch事件的代理里面实现Target方法、并把label的颜色改改，这样才像button，我把代理方法写在了extension延展里面，因为我见苹果都这样

extension MyViewButton{
	override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
		self.titleLabel.textColor = UIColor.lightGrayColor()
		if self.controlEvents == MyControlEvents.TouchDown{
			self.target?.performSelector(self.action!, withObject: self)
		}
	}
	override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
		self.titleLabel.textColor = UIColor.blueColor()
		//let point:CGPoint = (touches as NSSet).anyObject()!.locationInView(self)、下面方法的合体
		let view = (touches as NSSet).anyObject()
		let point:CGPoint = view!.locationInView(self)
		//判断Target类型和触摸点移出情况相匹配时执行target方法

	   if CGRectContainsPoint(self.bounds, point) && self.controlEvents == MyControlEvents.TouchUpInside{
			self.target?.performSelector(self.action!, withObject: self)
		}else if !CGRectContainsPoint(self.bounds, point) && self.controlEvents == MyControlEvents.TouchUpOutside{
			self.target?.performSelector(self.action!, withObject: self)
		}
}

d、在VC中实现，选择不同的点击类型即可监控不同的点击事件啦

class ViewController: UIViewController , MyViewButtonDelegate {
	var myButton:MyViewButton?
	override func viewDidLoad() {
		super.viewDidLoad()
		//从xib中加载我们自定义的view，我的xib叫做“View”
		let bundel:NSBundle = NSBundle.mainBundle()
		let views:Array = bundel.loadNibNamed("View", owner: nil, options: nil)
		self.myButton = views.last as? MyViewButton
		self.myButton?.frame = CGRectMake(80, 200, 200, 100)
		self.view.addSubview(self.myButton!)
		self.myButton?.addTarget(self, action: Selector!("didTapButton:"), forMyControlEvents: MyControlEvents.TouchUpInside)
}

最后 实现点击方法即可

func didTapButton(button:MyViewButton){
        print("VC点击了按钮---点击类型是\(button.controlEvents)")
    }

B、协议

1、声明一个protocol，里面有三个可选实现的方法，并把自身当做参数带出去

objc protocol MyViewButtonDelegate:NSObjectProtocol{
    optional func didTouchMyButton(button:MyViewButton)
    optional func didTouchUpInsideButton(button:MyViewButton)
    optional func didTouchUpOutsideButton(button:MyViewButton)
}

2、声明一个delegate属性，同样是弱指针引用

weak var delegate:MyViewButtonDelegate!

3、同样在touch事件中实现

extension MyViewButton{
	//调用协议方法时判断一下delegate和协议方法是否存在
	override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
		self.titleLabel.textColor = UIColor.lightGrayColor()
		if self.delegate != nil && self.delegate!.respondsToSelector("didTouchMyButton:"){
			self.delegate?.didTouchMyButton!(self)
		}
	}
	override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
		self.titleLabel.textColor = UIColor.blueColor()
		//let point:CGPoint = (touches as NSSet).anyObject()!.locationInView(self)
		let view = (touches as NSSet).anyObject()
		let point:CGPoint = view!.locationInView(self)
		if CGRectContainsPoint(self.bounds, point){
			if self.delegate != nil && self.delegate!.respondsToSelector("didTouchUpInsideButton:"){
				self.delegate?.didTouchUpInsideButton!(self)
			}		   
		}else{
			if self.delegate != nil && self.delegate!.respondsToSelector("didTouchUpOutsideButton:"){
				self.delegate?.didTouchUpOutsideButton!(self)
			}
		}
	}
}

4、在VC中实现即可

class ViewController: UIViewController , MyViewButtonDelegate {
 override func viewDidLoad() {
		super.viewDidLoad()
		let bundel:NSBundle = NSBundle.mainBundle()
		let views:Array = bundel.loadNibNamed("View", owner: nil, options: nil)
		self.myButton = views.last as? MyViewButton
		self.myButton?.frame = CGRectMake(80, 200, 200, 100)
		self.view.addSubview(self.myButton!)
		//设置button的代理
		self.myButton!.delegate = self
}
extension ViewController{
	//实现代理方法
	func didTouchMyButton(button: MyViewButton) {
		print("delegate--VC点击了button")
	}
	func didTouchUpInsideButton(button: MyViewButton) {
		print("delegate--TouchUpInside")
	}
	func didTouchUpOutsideButton(button: MyViewButton) {
		print("delegate--TouchUpOutside")
	}
}

C、闭包(block)

1、首先在自定义view里实现，相当于typedef一个block类型

typealias MyBlock = (button:MyViewButton)->Void

2、声明三个block属性，并且声明三个给block赋值方法

var TouchBlockHandel:MyBlock?
var TouchUpInsideBlockHandel:MyBlock?
var TouchUpOutsideBlockHandel:MyBlock?
//也可以不写方法直接属性赋值
func setMyTouchBlock(block:MyBlock){
	self.TouchBlockHandel = block
}
func setMyTouchUpInsideBlock(block:MyBlock){
	self.TouchUpInsideBlockHandel = block
}
func setMyTouchUpOutsideBlock(block:MyBlock){
	self.TouchUpOutsideBlockHandel = block
}

3、在touch事件中实现block

extension MyViewButton{
	override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
		self.titleLabel.textColor = UIColor.lightGrayColor()
		self.TouchBlockHandel!(button: self)
	}
	override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
		self.titleLabel.textColor = UIColor.blueColor()
		//let point:CGPoint = (touches as NSSet).anyObject()!.locationInView(self)
		let view = (touches as NSSet).anyObject()
		let point:CGPoint = view!.locationInView(self)
		if CGRectContainsPoint(self.bounds, point){
		self.TouchUpInsideBlockHandel!(button: self)  
		}else{
		self.TouchUpOutsideBlockHandel!(button: self)
		}
}

4、同样在VC中给三个block赋值即可

class ViewController: UIViewController , MyViewButtonDelegate {
	var myButton:MyViewButton?
	override func viewDidLoad() {
		super.viewDidLoad()
		let bundel:NSBundle = NSBundle.mainBundle()
		let views:Array = bundel.loadNibNamed("View", owner: nil, options: nil)
		self.myButton = views.last as? MyViewButton
		self.myButton?.frame = CGRectMake(80, 200, 200, 100)
		self.view.addSubview(self.myButton!)
		self.myButton?.setMyTouchBlock({ (button:MyViewButton) -> Void in
			print("block--VC点击了button")
		})
		self.myButton?.setMyTouchUpInsideBlock({ (button:MyViewButton) -> Void in
			print("block--VCTouchUpInside")
		})
		self.myButton?.setMyTouchUpOutsideBlock({ (button:MyViewButton) -> Void in
			print("block--VCTouchUpOutside")
		})
	}
}

最后来看看三个方法写在一起的打印结果。就添加了一个target监控TouchUpInside。总体来说和OC逻辑没有任何变化，只是语法上有所不同，block还是好用

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