Object reference not set to an instance of an object

Hello if i run the Code on Unity i get this error:

NullReferenceException: Object reference not set to an instance of an object
MenuManager.OpenMenu (System.String menuName) (at Assets/Scripts/MenuManager.cs:20)
Launcher.OnJoinedLobby () (at Assets/Scripts/Launcher.cs:24)
Photon.Realtime.LobbyCallbacksContainer.OnJoinedLobby () (at Assets/Photon/PhotonRealtime/Code/LoadBalancingClient.cs:4347)
Photon.Realtime.LoadBalancingClient.OnOperationResponse (ExitGames.Client.Photon.OperationResponse operationResponse) (at Assets/Photon/PhotonRealtime/Code/LoadBalancingClient.cs:2893)
ExitGames.Client.Photon.PeerBase.DeserializeMessageAndCallback (ExitGames.Client.Photon.StreamBuffer stream) (at C:/Dev/photon-sdk-dotnet/PhotonDotNet/PeerBase.cs:872)
ExitGames.Client.Photon.EnetPeer.DispatchIncomingCommands () (at C:/Dev/photon-sdk-dotnet/PhotonDotNet/EnetPeer.cs:583)
ExitGames.Client.Photon.PhotonPeer.DispatchIncomingCommands () (at C:/Dev/photon-sdk-dotnet/PhotonDotNet/PhotonPeer.cs:1771)
Photon.Pun.PhotonHandler.Dispatch () (at Assets/Photon/PhotonUnityNetworking/Code/PhotonHandler.cs:226)
Rethrow as AggregateException: Caught 1 exception(s) in methods called by DispatchIncomingCommands(). Rethrowing first only (see above). (Object reference not set to an instance of an object)
Photon.Pun.PhotonHandler.Dispatch () (at Assets/Photon/PhotonUnityNetworking/Code/PhotonHandler.cs:244)
Photon.Pun.PhotonHandler.FixedUpdate () (at Assets/Photon/PhotonUnityNetworking/Code/PhotonHandler.cs:145)

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class MenuManager : MonoBehaviour
6. {
7.     public static MenuManager instance;
8.  
9.     [SerializeField] Menu[] menus;
10.  
11.     private void Awake()
12.     {
13.         instance = this;
14.     }
15.  
16.     public void OpenMenu(string menuName)
17.     {
18.         for(int i = 0; i < menus.Length; i++)
19.         {
20.             if(menus[i].name == menuName)
21.             {
22.                 OpenMenu(menus[i].name);
23.             }
24.             else if(menus[i].open)
25.             {
26.                 CloseMenu(menus[i]);
27.             }
28.         }
29.     }
30.  
31.     public void OpenMenu(Menu menu)
32.     {
33.         for (int i = 0; i < menus.Length; i++)
34.         {
35.             if (menus[i].open)
36.             {
37.                 CloseMenu(menus[i]);
38.             }
39.         }
40.         menu.Open();
41.     }
42.     public void CloseMenu(Menu menu)
43.     {
44.         menu.Close();
45.     }
46. }

 

OP has menu.Open() which probably is fine. It appears to be a single instance of the Menu class.

My initial guess is that menus is uninitialized. Makes sure it's not.

Also, I'd be inclined to get rid of your CloseMenu() function, menu's have their own Close function so there's no need to have a separate function to do it. Though that's just personal preference. Do what you want

 

Here is the code it should work with.

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class Menu : MonoBehaviour
6. {
7.     public string menuName;
8.     public bool open;
9.  
10.     public void Open()
11.     {
12.         open = true;
13.         gameObject.SetActive(true);
14.     }
15.  
16.     public void Close()
17.     {
18.         open = false;
19.         gameObject.SetActive(false);
20.     }
21. }
22.  

 

If you set the Menu object to inactive in the hierarchy then the Menu component on it is also no longer active, hence the error you're getting.

 

Also, as this is networking, remember there is no in-built mechanism to ensure the menu is still around when your JoinLobby message comes in.

IOW, if you say join lobby and that menu reference is null, it is up to you to guard that everything in the delegate is still valid at the moment the join callback fires. Or else disconnect the delegate when it isn't. Otherwise you will see this behavior.

Networking is extremely abstract and advanced and difficult to reason about, so it's important to code defensively and thoroughly.

It's still the same story however;

How to fix a NullReferenceException error

https://forum.unity.com/threads/how-to-fix-a-nullreferenceexception-error.1230297/

Three steps to success:
- Identify what is null
- Identify why it is null
- Fix that

 

The code should just close the loading menu if its loaded and open the title menu

 

It ain't closing no menu that either a) doesn't exist, or b) you don't have a valid reference to.

Start there.

 

thanks

 

hmm, I think is your awake function there, try not to make it private

 

Unity will call any of the 'magic methods' (Awake, Start, etc) regardless of its protection level.

 

Hello I am also having this problem we are probably following the same tutorial video

. I was wondering if OP found a fix