Swift闭包和OC block类型的使用

之前看过一段swift，一直不知道OC中的block，即swift中的闭包是怎么实现的。今天就在网上搜索了一下，同时对比了一下OC中block类型的实现方法，然后写了一个Demo测试一下。

使用说明：

swift版本

1.声明类型 typealias hideShowView = (Int) -> Void
2.声明属性 var muFunc:hideShowView?
3.传递参数 func didSelectedToHideView(hideFunc:@escaping (Int)->Void) { muFunc = hideFunc }
4.监听值的变化 func tapEvent() { muFunc!(0) }
5.使用 showView.didSelectedToHideView { (para) in NSLog("%d", para) }
6.Void 是返回值类型，Int是参数类型，hideShowView是闭包的类型名称.第5项中的para是闭包的参数名，经测试，这个参数名在使用闭包的时候可以任意修改

OC版本

.h文件

//声明一个block类型
typedef void(^HideShowViewBlock)(int index); 

//声明一个block属性
@property (nonatomic,copy) HideShowViewBlock hideViewBlock;

//传递参数的方法
 - (void)didHideShowViewWithBlock:(HideShowViewBlock)hideViewBlock;

.m文件

//实现传递参数的函数
- (void)didHideShowViewWithBlock:(HideShowViewBlock)hideViewBlock
{
    self.hideViewBlock = hideViewBlock;
}
//监听需要传递值的变化
- (void)tapEvent
{
    self.hideViewBlock(0);
}

swift 闭包 Demo的代码

class ShowView: UIView
{

    typealias hideShowView = (Int) -> Void
    var muFunc:hideShowView?

    private var viewFram:CGRect?

    override  init(frame:CGRect )
    {
        super.init(frame: frame)
        self.viewFram = frame
        self.backgroundColor = UIColor.gray
        self.createUI()
    }

    func createUI()
    {
        var centerLabel = UILabel.init(frame: CGRect.init(x: 0, y: 0, width: (self.viewFram?.width)!, height: 20))
        centerLabel.center = self.center
        centerLabel.text = "测试"
        centerLabel.textColor = UIColor.white
        centerLabel.textAlignment = NSTextAlignment.center
        centerLabel.font = UIFont.boldSystemFont(ofSize: 16.0)
        self.addSubview(centerLabel)

        let tap = UITapGestureRecognizer.init(target: self, action: #selector(ShowView.tapEvent))
        tap.cancelsTouchesInView = false
        self.addGestureRecognizer(tap)
    }

    func tapEvent()
    {
        muFunc!(0)
    }

    func didSelectedToHideView(hideFunc:@escaping (Int)->Void)
    {
        muFunc = hideFunc
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

class ViewController: UIViewController
{

    let WIDTH = UIScreen.main.bounds.size.width
    let HEIGHT = UIScreen.main.bounds.size.height


    override func viewDidLoad()
    {
        super.viewDidLoad()
    }

    @IBAction func selectedToDoSomething(_ sender: UIButton)
    {
        let showView = ShowView.init(frame: CGRect.init(x: 0, y: 0, width: WIDTH/2, height: WIDTH/2))
        showView.center = self.view.center
        showView.didSelectedToHideView { (para) in
            NSLog("%d", para)
        }
        self.view.addSubview(showView)
    }
    override func didReceiveMemoryWarning()
    {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
}

不足的地方，还请各位多多指教，在此多谢了。