EventManager with parameters

Question

So I'm using the EventManager code from t$$anonymous$$s Unity tutorial, I figured it would help clean up my beginner project. Although I would like to be able to pass a parameter with UnityAction.

In the tutorial, every function that is added as a listener is one without any parameters.

I was hoping I could find a way to do t$$anonymous$$s without too much trouble, but I spent a w$$anonymous$$le researc$$anonymous$$ng it, and it seems like the most popular answer is to use delegates/Action instead... I tried modifying it myself, and I feel like I was close, but I'm lost at the moment.

I'd rather avoid that extra work of rewriting what I've done, so here I am.

For an example of what I'd like to do, I was hoping that I could do somet$$anonymous$$ng like t$$anonymous$$s in my code, it's invalid code, but it's basically what I'm trying to ac$$anonymous$$eve:

 void Awake()
 {
     someListener = new UnityAction (SomeFunction); //<---Can't do t$$anonymous$$s
 }
 
 void SomeFunction(GameObject someObject)  //<--- Because t$$anonymous$$s has a parameter
 {
     doSomet$$anonymous$$ng();
 }

Below you can see what I mean, where the original examples are.

The EventTest.cs:

 public class EventTest : MonoBehaviour
 {
     private UnityAction someListener;

     void Awake ()
     {
         someListener = new UnityAction (SomeFunction);  //<---T$$anonymous$$s works,
     }

     void OnEnable ()
     {
         EventManager.StartListening ("test", someListener);
     }

     void SomeFunction ()  //<---Because no parameter here!
     {
         Debug.Log ("Some Function was called!");
     }
 }

And they call the TriggerEvent in another class, so it's not directly referencing EventTest:

 public class EventTriggerTest : MonoBehaviour {

     void Update () {
         if (Input.GetKeyDown ("q"))
         {
             EventManager.TriggerEvent ("test");    //No need to reference EventTest! Hooray!
         }
 }

And here is the EventManager.cs:

 public class EventManager : MonoBehaviour {
 
     private Dictionary <string, UnityEvent> eventDictionary;
     private static EventManager eventManager;
 
     public static EventManager instance
     {
         get
         {
             if (!eventManager)
             {
                 eventManager = FindObjectOfType (typeof (EventManager)) as EventManager;
 
                 if (!eventManager)
                     Debug.LogError ("Need 1 active EventManger script on GameObject in your scene.");
                 else
                     eventManager.Init(); 
             }
             return eventManager;
         }
     }
 
     void Init ()
     {
         if (eventDictionary == null)
             eventDictionary = new Dictionary<string, UnityEvent>();
     }
 
     public static void StartListening (string eventName, UnityAction listener)
     {
         UnityEvent t$$anonymous$$sEvent = null;
         if (instance.eventDictionary.TryGetValue (eventName, out t$$anonymous$$sEvent))
             t$$anonymous$$sEvent.AddListener (listener);
         else
         {
             t$$anonymous$$sEvent = new UnityEvent ();
             t$$anonymous$$sEvent.AddListener (listener);
             instance.eventDictionary.Add (eventName, t$$anonymous$$sEvent);
         }
     }
 
     public static void StopListening (string eventName, UnityAction listener)
     {
         if (eventManager == null) return;
         UnityEvent t$$anonymous$$sEvent = null;
         if (instance.eventDictionary.TryGetValue (eventName, out t$$anonymous$$sEvent))
             t$$anonymous$$sEvent.RemoveListener (listener);
     }
 
     public static void TriggerEvent (string eventName)
     {
         UnityEvent t$$anonymous$$sEvent = null;
         if (instance.eventDictionary.TryGetValue (eventName, out t$$anonymous$$sEvent))
             t$$anonymous$$sEvent.Invoke ();
     }
 }

Answer 1

I essentially found the answer to my question here, under the "With Parameter" section. Although it's using Action instead of UnityEvent, it's basically the same t$$anonymous$$ng: https://stackoverflow.com/questions/42034245/unity-eventmanager-with-delegate-instead-of-unityevent

 using System;
 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class EventManager : MonoBehaviour
 {
 
     private Dictionary<string, Action<EventParam>> eventDictionary;
 
     private static EventManager eventManager;
 
     public static EventManager instance
     {
         get
         {
             if (!eventManager)
             {
                 eventManager = FindObjectOfType(typeof(EventManager)) as EventManager;
 
                 if (!eventManager)
                 {
                     Debug.LogError("There needs to be one active EventManger script on a GameObject in your scene.");
                 }
                 else
                 {
                     eventManager.Init();
                 }
             }
             return eventManager;
         }
     }
 
     void Init()
     {
         if (eventDictionary == null)
         {
             eventDictionary = new Dictionary<string, Action<EventParam>>();
         }
     }
 
     public static void StartListening(string eventName, Action<EventParam> listener)
     {
         Action<EventParam> t$$anonymous$$sEvent;
         if (instance.eventDictionary.TryGetValue(eventName, out t$$anonymous$$sEvent))
         {
             //Add more event to the existing one
             t$$anonymous$$sEvent += listener;
 
             //Update the Dictionary
             instance.eventDictionary[eventName] = t$$anonymous$$sEvent;
         }
         else
         {
             //Add event to the Dictionary for the first time
             t$$anonymous$$sEvent += listener;
             instance.eventDictionary.Add(eventName, t$$anonymous$$sEvent);
         }
     }
 
     public static void StopListening(string eventName, Action<EventParam> listener)
     {
         if (eventManager == null) return;
         Action<EventParam> t$$anonymous$$sEvent;
         if (instance.eventDictionary.TryGetValue(eventName, out t$$anonymous$$sEvent))
         {
             //Remove event from the existing one
             t$$anonymous$$sEvent -= listener;
 
             //Update the Dictionary
             instance.eventDictionary[eventName] = t$$anonymous$$sEvent;
         }
     }
 
     public static void TriggerEvent(string eventName, EventParam eventParam)
     {
         Action<EventParam> t$$anonymous$$sEvent = null;
         if (instance.eventDictionary.TryGetValue(eventName, out t$$anonymous$$sEvent))
         {
             t$$anonymous$$sEvent.Invoke(eventParam);
             // OR USE  instance.eventDictionary[eventName](eventParam);
         }
     }
 }

EventManager with parameters

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