我的协议没有调用

Question

我正在使用协议调用方法，但我的方法没有调用。有没有我使用的示例。

这是我的代码：

视图控制器

    class ViewController: UIViewController {
      override func viewDidLoad() {
        super.viewDidLoad()
                // Do any additional setup after loading the view.
    }


extension ViewController :ViewController1Delegate
{
    func hello()
    {
        println("hbgyguyg");
    }
}

在视图控制器 1 中

import UIKit
@objc
protocol ViewController1Delegate
{
   optional func hello()
}
class ViewController1: UIViewController {
 var delegate: ViewController?
    override func viewDidLoad() {
        super.viewDidLoad()
                    delegate?.hello()
             }

}

请帮助，我是 Swift 的新手。任何帮助都会得到帮助。提前致谢

Answer 1

一个示例演示。

ViewController 文件

import UIKit

class ViewController: UIViewController, PopUpViewControllerDelegate
{
    var popupVC: PopUpViewController!;

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        self.view!.backgroundColor = UIColor.whiteColor();

        self.popupVC = PopUpViewController();
        self.popupVC.delegate = self;


        self.showPopUpVC();
    }

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


    func popUpViewControllerDidPressOK(popUpVC: PopUpViewController) {

        println("Yay?");

        self.closePopUpVC();
    }

    func showPopUpVC()
    {
        let delayTime = dispatch_time(DISPATCH_TIME_NOW,
            Int64(1.0 * Double(NSEC_PER_SEC)))

        dispatch_after(delayTime, dispatch_get_main_queue()) {

            self .presentViewController(self.popupVC, animated: true, completion: nil);

        }
    }

    func closePopUpVC()
    {
        let delayTime = dispatch_time(DISPATCH_TIME_NOW,
            Int64(1.0 * Double(NSEC_PER_SEC)))

        dispatch_after(delayTime, dispatch_get_main_queue()) {

            self.dismissViewControllerAnimated(true, completion: nil);

        }
    }
}

PopUpViewController 文件

import UIKit

protocol PopUpViewControllerDelegate
{
    func popUpViewControllerDidPressOK(popUpVC: PopUpViewController);
}

class PopUpViewController: UIViewController {

    var delegate: PopUpViewControllerDelegate!;

    override func viewDidLoad() {
        super.viewDidLoad()

        self.view!.backgroundColor = UIColor.redColor();

        // Do any additional setup after loading the view.

        self.delegate!.popUpViewControllerDidPressOK(self);
    }

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

请注意，在我的 ViewController viewDidLoad() 方法中，我有一行初始化弹出视图控制器，然后将其委托设置为 ViewController 本身：

self.popupVC = PopUpViewController();
self.popupVC.delegate = self; // you're missing this line I believe ?

我不使用 Interface Builder 或 Storyboard，但可能会在 Storyboard 中选择您的 VC1，然后查看连接检查器，看看您是否将一行从“delegate”拖到您的 ViewController 文件所有者的东西上。

最后，您应该会在 1 秒后看到一个红色屏幕弹出窗口，然后是“Yay?”这个词。登录到你的 Xcode 控制台，最后 popupVC 消失了。