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//
// SecondViewController.swift
// 页面传值
//
// Created by SZT on 2016/11/4.
// Copyright © 2016年 SZT. All rights reserved.
//

import UIKit

//从后往前传值的协议
protocol secondProtocol{
//需要传什么类型的参数，参数列表就写什么
func translateString(str:String)

}

class SecondViewController: UIViewController {
//定义labelStr属性，负责接收前一个页面传过来的值
var labelStr:String?
var textField:UITextField?

//定义代理属性
var delegate:secondProtocol?

override func viewDidLoad() {
    super.viewDidLoad()
    //创建文本框textField
    textField = UITextField(frame: CGRectMake(50, 150, 90, 40))
    textField?.borderStyle = .RoundedRect
    textField?.placeholder = "请输入内容"
    //将传过来的值显示出来
    textField?.text = labelStr
    view.addSubview(textField!)
    view.backgroundColor = UIColor.whiteColor()
    navigationItem.title = "SecondVC"
    let btn = UIButton(frame: CGRectMake(50,200,90,40))
    btn.backgroundColor = UIColor.grayColor()
    btn.setTitle("pop", forState: .Normal)
    btn.addTarget(self, action: "popToFirstVC", forControlEvents: .TouchUpInside)
    view.addSubview(btn)
    
    let modelBtn = UIButton(frame: CGRectMake(50,260,90,40))
    modelBtn.backgroundColor = UIColor.cyanColor()
    modelBtn.setTitle("模态显示", forState: .Normal)
    modelBtn.addTarget(self, action: "modelToThird", forControlEvents: .TouchUpInside)
    view.addSubview(modelBtn)
}

func modelToThird(){
    let thirdVC = ThirdViewController()
    presentViewController(thirdVC, animated: true, completion: nil)
}

func popToFirstVC(){
    //代理传值
    delegate?.translateString((textField?.text)!)
    navigationController?.popViewControllerAnimated(true)
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


/*
 // MARK: - Navigation
 
 // In a storyboard-based application, you will often want to do a little preparation before navigation
 override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
 // Get the new view controller using segue.destinationViewController.
 // Pass the selected object to the new view controller.
 }
 */

}