resolve survicate delegate issue in ios

Author: Hamed Rezaee

ios/Classes/SwiftSurvicateFlutterSdkPlugin.swift

@@ -3,20 +3,25 @@ import UIKit
 
 import Survicate
 
-public class SwiftSurvicateFlutterSdkPlugin: NSObject, FlutterPlugin, SurvicateDelegate {
-    
+public class SwiftSurvicateFlutterSdkPlugin: NSObject, FlutterPlugin {
+    private var survicateDelegate: FlutterSurvicateDelegate?
+
     class FlutterChannel: NSObject {
         static let shared: FlutterChannel = FlutterChannel()
+
         var channel: FlutterMethodChannel?
+
         private override init() {}
     }
 
     public static func register(with registrar: FlutterPluginRegistrar) {
         let channel = FlutterMethodChannel(name: "survicate_flutter_sdk", binaryMessenger: registrar.messenger())
         let instance = SwiftSurvicateFlutterSdkPlugin()
+
+        instance.survicateDelegate = FlutterSurvicateDelegate(channel)
         registrar.addMethodCallDelegate(instance, channel: channel)
-        
         FlutterChannel.shared.channel = channel
+
         Survicate.shared.initialize()
     }
 
@@ -25,18 +30,23 @@ public class SwiftSurvicateFlutterSdkPlugin: NSObject, FlutterPlugin, SurvicateD
 
         if (call.method == "invokeEvent") {
             let eventName = arguments["eventName"]  ?? ""
+
             Survicate.shared.invokeEvent(name: eventName)
+
             result(true)
         } else if (call.method == "enterScreen") {
             let screenName = arguments["screenName"]  ?? ""
+
             Survicate.shared.enterScreen(value: screenName)
+
             result(true)
         } else if (call.method == "leaveScreen") {
             let screenName = arguments["screenName"]  ?? ""
+
             Survicate.shared.leaveScreen(value: screenName)
+
             result(true)
         } else if (call.method == "setUserTraits") {
-            
             var traits = [UserTrait]()
 
             for (key, value) in arguments {
@@ -48,45 +58,59 @@ public class SwiftSurvicateFlutterSdkPlugin: NSObject, FlutterPlugin, SurvicateD
             result(true)
         } else if (call.method == "reset") {
             Survicate.shared.reset()
+
             result(true)
         } else if (call.method == "registerSurveyListeners") {
-            Survicate.shared.delegate = self
+            Survicate.shared.delegate = survicateDelegate
+
             result(true)
         } else if (call.method == "unregisterSurveyListeners") {
             Survicate.shared.delegate = nil
+
             result(true)
-        }else {
+        } else {
             result(FlutterMethodNotImplemented)
         }
     }
+}
+
+class FlutterSurvicateDelegate : SurvicateDelegate {
+    let channel: FlutterMethodChannel?
+    
+    init(_ channel: FlutterMethodChannel) {
+        self.channel = channel
+    }
 
     public func surveyDisplayed(surveyId: String) {
         let arguments = ["surveyId": surveyId]
+
         DispatchQueue.main.async {
-            FlutterChannel.shared.channel?.invokeMethod("onSurveyDisplayed", arguments: arguments)
+            self.channel?.invokeMethod("onSurveyDisplayed", arguments: arguments)
         }
     }
 
     public func questionAnswered(surveyId: String, questionId: Int, answer: SurvicateAnswer) {
         let answerMap = ["type": answer.type as Any, "id": answer.id as Any , "ids": answer.ids as Any , "value" : answer.value as Any] as [String : Any]
-        
         let arguments = ["surveyId": surveyId, "questionId": questionId, "answer": answerMap] as [String : Any]
+
         DispatchQueue.main.async {
-            FlutterChannel.shared.channel?.invokeMethod("onQuestionAnswered", arguments: arguments)
+            self.channel?.invokeMethod("onQuestionAnswered", arguments: arguments)
         }
     }
 
     public func surveyCompleted(surveyId: String) {
         let arguments = ["surveyId": surveyId]
+
         DispatchQueue.main.async {
-            FlutterChannel.shared.channel?.invokeMethod("onSurveyCompleted", arguments: arguments)
+            self.channel?.invokeMethod("onSurveyCompleted", arguments: arguments)
         }
     }
 
     public func surveyClosed(surveyId: String) {
         let arguments = ["surveyId": surveyId]
+        
         DispatchQueue.main.async {
-            FlutterChannel.shared.channel?.invokeMethod("onSurveyClosed", arguments: arguments)
+            self.channel?.invokeMethod("onSurveyClosed", arguments: arguments)
         }
     }
 }