Swift   发布时间:2022-03-31  发布网站:大佬教程  code.js-code.com
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概述

具体的代码,详见Demo:链接: http://pan.baidu.com/s/1gdkyWE3 密码: 4mhv rootViewController class ViewController: UIViewController,GetmessageDelegate { var _button:UIButton? var _label:UILabel? override

@H_301_1@具体的代码,详见Demo:链接: http://pan.baidu.com/s/1gdkyWE3 密码: 4mhv


rootViewController

class ViewController: UIViewController,GetmessageDelegate
{
    var _button:UIButton?
    var _label:UILabel?

    override func viewDidLoad()
    {
        super.viewDidLoad()
        
        self.title = "RootViewController"
        //创建label 用来接收传过来的值
        _label = UILabel(frame: CGRect(x: 50,y: 100,width: 220,height: 44))
        _label?.text = "get message from next page"
        
        _label?.textAlignment = NSTextAlignment.Center
        _label?.BACkgroundColor = UIColor.cyanColor()
        self.view.addSubview(_label!)
        
        //创建button 点击跳转到下一个界面
        _button = UIButton(frame:CGRect(x:60,y:200,width:200,height:44))
        _button?.settitle("go to next page",forState: UIControlState.Normal)
        _button?.settitleColor(UIColor.yellowColor(),forState: UIControlState.Normal)
        _button?.BACkgroundColor = UIColor.blueColor()
        _button?.addTarget(self,action: "nextPage",forControlEvents: UIControlEvents.TouchUpInsidE)
        self.view.addSubview(_button!)
    }

    //push
    func nextPage()
    {
        let nextVC = NextViewController()
        //指定代理
        nextVC.delegate = self
        self.navigationController!.pushViewController(nextVC,animated:truE)
    }
    //接收传过来的值
    func getmessage(controller:NextViewController,String:string)
    {
        _label?.text = String
        if(String == "")
        {
            _label?.text = "null"
        }
 
    }


}

secondViewController

//创建协议
protocol GetmessageDelegate:NSObjectProtocol
{
    //回调方法一个String类型的值
    func getmessage(controller:NextViewController,String:string)
}
class NextViewController: UIViewController
{
    var delegate:GetmessageDelegate?
    var _textField:UITextField?
    override func viewDidLoad()
    {
        super.viewDidLoad()
        self.title = "SecondViewController"
        self.view.BACkgroundColor = UIColor.whiteColor()
        
        //创建textField 用来输入要传的值
        _textField = UITextField(frame: CGRect(x: 60,width: 200,height: 44))
        _textField?.borderstyle = UITextBorderstyle.RoundedRect
        _textField?.placeholder = "input sth to send BACk"
        self.view.addSubview(_textField!)

        //创建返回的button
        var myButton = UIButton(frame:CGRect(x:60,height:44))
        myButton.center = CGPointMake(160,200)
        myButton.settitle("send message BACk",forState:.Normal)
        myButton.addTarget(self,action:"goBACk",forControlEvents:.TouchUpInsidE)
        myButton.BACkgroundColor = UIColor.blueColor()
        self.view.addSubview(myButton)
    }

    func goBACk()
    {
        //调用代理方法
        if((delegatE) != nil)
        {
            delegate?.getmessage(self,String:_textField!.text)
            self.navigationController?.popToRootViewControllerAnimated(true)
        }
        
    }
}

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