第一个视图控制器:
import UIKit
// 遵循协议
class ViewController: UIViewController,SecondVCDelegate
{
override func viewDidLoad() {
super.viewDidLoad()
// 创建一个button
let button1 = UIButton(frame: CGRectMake(120, 120, 50, 50))
// 修改背景颜色
button1.backgroundColor = UIColor.redColor()
self.view.addSubview(button1)
// 点击方法
button1.addTarget(self, action: "buttonAction:", forControlEvents: UIControlEvents.TouchUpInside)
}
// button点击方法
func buttonAction(sender:UIButton){
// 跳转下一个界面
let secondVC = SecondViewController()
// 属性传值
secondVC.passValue = "咻"
// 指定代理
// secondVC.delegate = self
// 定义block
secondVC.block = { (tempColor:UIColor)->Void in
self.view.backgroundColor = tempColor
}
self.navigationController?.pushViewController(secondVC, animated: true)
}
// 实现代理方法
func changeColor(tempColor: UIColor) {
self.view.backgroundColor = tempColor
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
/*************************************************************/
代理的六大步骤
1.后页面制定协议
2.前页面代理遵循协议
3.后页面设置代理属性
4.前页面指定代理self
5.后页面发送代理方法命令
6.前页面代理实现代理方法
第二个视图控制器:
import UIKit
protocol SecondVCDelegate {
// 协议中的方法
func changeColor(tempColor:UIColor)
}
class SecondViewController: UIViewController {
// 属性
var passValue:String?
// 代理属性
var delegate:SecondVCDelegate?
// block属性
var block:((UIColor)->Void)?
override func viewDidLoad() {
super.viewDidLoad()
self.view.backgroundColor = UIColor.cyanColor()
print(self.passValue!)
self.title = self.passValue
// 返回button
let button2 = UIButton(frame: CGRectMake(120, 120, 50, 50))
button2.backgroundColor = UIColor.blackColor()
button2.addTarget(self, action: "button2Action:", forControlEvents: UIControlEvents.TouchUpInside)
self.view.addSubview(button2)
}
// button2点击方法
func button2Action(sender:UIButton) {
// 发送代理方法命令
// self.delegate?.changeColor(UIColor.redColor())
// 调用block
self.block!(UIColor.redColor())
// 返回
self.navigationController?.popViewControllerAnimated(true)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}