我的委托函数没有在 Swift 中被调用

Question

我有一个名为 NoteTakerViewController 的主视图。我有一个带有协议的weatherGetterController 类，该类使用一个名为getMyWeather 的协议函数返回5 天的天气。但是，没有调用将天气数据返回给 NoteTakerViewController 的协议函数。我确信我已经与代表正确设置了所有内容，但也许我没有。

这确实不是 Swift Delegate Not Being Called 的重复，因为该页面上的解决方案不起作用。

您能提供的任何帮助都会很棒。

这里是相关代码sn-ps：

我的 weatherGetterController 类：

protocol WeatherGetterControllerDelegate {
    func getMyWeather(weather: [FiveDayForecast])
}

class WeatherGetterController: UIViewController, CLLocationManagerDelegate {

var weatherGetterDelegate: WeatherGetterControllerDelegate?

并在 WeatherGetterController 中调用“getWeather”函数。线

self.weatherGetterDelegate?.getMyWeather(weather: myForecast)

没有被调用。

func getWeather() {
       ...
       getNetWeather { (fetchedInfo) in

            if let fetchedInfo2 = fetchedInfo {
                //self.updateUI(mainWeather: fetchedInfo2)
                //need to call delegate here
                let myForecast = self.figureFive(weather: fetchedInfo2)
                //return the forecast
                print(myForecast)
                self.weatherGetterDelegate?.getMyWeather(weather: myForecast)

            }

        }

最后是NoteTakerViewController中的函数实现：

class NoteTakerViewController: UIViewController, ..., UITextFieldDelegate, WeatherGetterControllerDelegate

    func getMyWeather(weather: [FiveDayForecast]) {

        print("get my weather")
        print(weather)

    }

通过调试我可以看到“weatherGetterDelegate”被设置为nil，我不知道为什么。

谢谢

Answer 1

首先，您需要将 WeatherGetterController 设为 NoteTakerViewController 中的属性或调用它的局部变量，但我将使用第一个选项。

class NoteTakerViewController: UIViewController, ..., WeatherGetterControllerDelegate {
    var weatherGetterController: WeatherGetterController?

    //...

    func viewDidLoad() {
         //....
         weatherGetterController = WeatherGetterController()
         weatherGetterController?.delegate = self
    }

   //And then in some other part of your code you do
   func someFunc() {
       self.weatherGetterController?.getWeather()

我很好奇为什么 WeatherGetterController 被定义为一个视图控制器，这真的正确吗？

class WeatherGetterController: UIViewController, CLLocationManagerDelegate {

我个人会删除那部分

lass WeatherGetterController: CLLocationManagerDelegate {

Answer 2

把它放在 WeatherGetterController 的 init 中

  public weak var weatherGetterDelegate: WeatherGetterControllerDelegate?

  /* if you are not initializing it anywhere else 
  and if you are initializing it anywhere else then make sure you are 
  initializing WeatherGetterController there too and then put delegate   
  of WeatherGetterController to NoteTakerViewController object
   else write the below code */

  var model = NoteTakerViewController()

   public override init() {
      self. weatherGetterDelegate = model
 }