ConnectionManager.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using UnityEngine.Networking.Match;
using UnityEngine.Networking;
using UnityEngine;

public class ConnectionManager : NetworkManager
{
    public GameObject managerPrefab;

    public GameObject activeManager;

    NetworkConnection clientConnection;
    bool joinedRoom = false;
    bool isHost = false;
    bool isClient = false;
    bool isServer = false;

    public void Update()
    {

    }

    public override void OnStopServer()
    {
        GameClosed();
    }

    public override void OnStopClient()
    {
        GameClosed();
    }

    public override void OnStartHost()
    {
        isHost = true;
    }

    public override void OnStartServer()
    {
        isServer = true;
        joinedRoom = true;
        activeManager = (GameObject)Instantiate(FindPrefab("Manager"), transform.position, transform.rotation);
        NetworkServer.Spawn(activeManager);
    }

    public override void OnStartClient(NetworkClient client)
    {
        isClient = true;
        joinedRoom = true;
        clientConnection = client.connection;
    }

    private void CloseGame()
    {
        if (isHost)
            StopHost();
        else if (isClient)
            StopClient();
        else
            StopServer();
    }

    private void GameClosed()
    {
        if (activeManager != null)
        {
            activeManager.BroadcastMessage("StopGame");
            NetworkServer.Destroy(activeManager);
        }
        joinedRoom = false;
        isServer = false;
        isClient = false;
        isHost = false;
    }

    public GameObject FindPrefab(string prefab)
    {
        return spawnPrefabs.First(p => p.name == prefab);
    }

    void OnGUI()
    {
        if (!joinedRoom)
        {
            if (GUILayout.Button("Start Local Server"))
                StartServer();
            if (GUILayout.Button("Start Local Host"))
                StartHost();
            if (GUILayout.Button("Start Client"))
                StartClient();
        }
        else if (!ClientScene.ready)
        {
            //ClientScene.Ready(clientConnection);
        }
        else
        {
            GUILayout.Label("Ready!");
        }
        if (joinedRoom)
            if (GUILayout.Button("Close"))
                CloseGame();
    }

}