Unity Mirror AddPlayerForConnection method didn't work as expected - unity3d

Question

I'm quite new to Mirror. Let me try to explain my setup and problem:
On client-side, player spawn multi-gameobject and select the only one which he would use in a race. For example, he has 4 cars in his garage, when the scene Garage is loaded, there are 4 car-object has been spawned in the scene. And when he select the desired car to use in a race, the Player property in PlayerManager instance will update with the selected car value.
public class PlayerManager : MonoBehaviour {
public static PlayManager Instance;
private void Awake() {
if (Instance != null) Destroy(gameObject);
Instance = this;
}
public Player Player {get; private set;}
public static void UpdateSelectedCar() {
Car car = CarSpawner.SelectedCar;
Player.Car = car;
}
}
public class Player () {
public Car Car { get; set; }
public string Name;
....
public Player(string playerName){
Name = playerName;
}
}
public class Car() {
public GameObject;
public CarName;
.....
public void Instantiate() {
GameObject = Object.Instantiate(carPrefab, carPosition);
}
}
In the NetworkManagerCar, I have setup as below:
public class NetworkManagerCar : NetworkManager {
// There are Host and Join Button in the UI for create host or join as client
private void OnEnable() {
hostBtn.onClick.AddListener(CreateHost);
joinBtn.onClick.AddListener(JoinGame);
}
private void OnDisable() {
hostBtn.onClick.RemoveListener(CreateHost);
joinBtn.onClick.RemoveListener(JoinGame);
}
private void CreateHost() {
StartHost();
networkStatus.text = "Waiting for other to join...";
}
private void JoinGame() {
StartClient();
networkStatus.text = "Finding Match...";
}
public override void OnClientConnect() {
PlayerManager.UpdateSelectedCar();
playerPrefab = PlayerManager.Instance.Player.Car.GameObject;
Debug.Log($"Prefab name: {playerPrefab.name}");
base.OnClientConnect();
Debug.Log($"{PlayerManager.Instance.Player.Name} connected");
}
public override void OnServerAddPlayer(NetworkConnectionToClient conn) {
GameObject player = playerPrefab;
player.name = $"{playerPrefab.name} [connId={conn.connectionId}]";
NetworkServer.AddPlayerForConnection(conn, player);
}
}
It is no problem when I host the game. However, when 1 client joined, I got the bug below. I use ParrelSync to clone client, I have already tried to delete the clone and create a new one but the bug is still:
On host console:
Object Car10(Clone) [connId=0] [connId=250806295] [connId=701038615] (Mirror.NetworkIdentity) netId=2 already has an owner. Use RemoveClientAuthority() first
UnityEngine.Debug:LogError (object,UnityEngine.Object)
On client console:
Spawn scene object not found for CE359B9F. Make sure that client and server use exactly the same project. This only happens if the hierarchy gets out of sync.
Could not spawn assetId=00000000-0000-0000-0000-000000000000 scene=CE359B9F netId=1
OnSpawn message with netId '2' has no AssetId or sceneId
Could anyone tell me where I was wrong :(

Answer 1

You need instantiate "playerPrefab" before passing to AddPlayerForConnection
GameObject player = Instantiate(playerPrefab);
player.name = $"{playerPrefab.name} [connId={conn.connectionId}]";
NetworkServer.AddPlayerForConnection(conn, player);