ios - 如何在初始化函数中将委托(delegate)设置为 self ？

Question

我有一个名为 MQTTController 的类，带有共享实例和私有(private)初始化方法

class MQTTController:NSObject, CocoaMQTTDelegate {
      static let sharedInstance = MQTTController()
      var clientID:String
      var mqtt:CocoaMQTT
      private override init() {
        clientID = "xyz-" + String(ProcessInfo().processIdentifier)
        mqtt = CocoaMQTT(clientID: clientID, host: "mqttcontroller.mqtt.net", port: 1883)
        mqtt.username = "myusername"
        mqtt.password = "mypassword"
        mqtt.willMessage = CocoaMQTTWill(topic: "/will", message: "dieout")
        mqtt.keepAlive = 30
        mqtt.cleanSession = true
        MQTTController.isConnecting = true
        mqtt.delegate = self    //Error at this Line "'self' used before super.init call"
        mqtt.connect()
    } 
}

在这里我知道我可以创建另一个方法来设置委托(delegate)并调用 mqtt.connect() 但我只想知道是否有任何解决方案我不必创建和调用另一个方法。

Answer 1

错误信息告诉你需要做什么，你需要在你的 init 中调用 super.init()。

class MQTTController:NSObject, CocoaMQTTDelegate {
    static let sharedInstance = MQTTController()
    var clientID:String
    var mqtt:CocoaMQTT
    private override init() {
        clientID = "xyz-" + String(ProcessInfo().processIdentifier)
        mqtt = CocoaMQTT(clientID: clientID, host: "mqttcontroller.mqtt.net", port: 1883)
        mqtt.username = "myusername"
        mqtt.password = "mypassword"
        mqtt.willMessage = CocoaMQTTWill(topic: "/will", message: "dieout")
        mqtt.keepAlive = 30
        mqtt.cleanSession = true
        MQTTController.isConnecting = true

        super.init() // This line was missing

        mqtt.delegate = self
        mqtt.connect()
    } 
}