made serverConnection true thread safe singleton

Server/Models/Information.cs

@@ -10,7 +10,11 @@ namespace Server.Models
     class Information : ObservableObject
     {
         public bool CanStartServer { get; set; }
-
         public bool ServerOnline { get; set; }
+        public string ServerStatus { get {
+               if (ServerOnline) return "Online";
+               return "Offline";
+            } 
+        }
     }
 }

Server/Models/ServerClient.cs

@@ -15,6 +15,7 @@ namespace Server.Models
         private byte[] buffer = new byte[1024];
         private byte[] totalBuffer = new byte[1024];
         private int totalBufferReceived = 0;
+        
 
         public ServerClient(TcpClient client)
         {
@@ -75,6 +76,7 @@ namespace Server.Models
         /// <param name="message">the incoming message</param>
         private void HandleIncomingMessage(byte[] message)
         {
+            Debug.WriteLine($"Got message from client : {message}");
             //TODO implement ways to handle the message
         }
 

Server/Models/ServerCommunication.cs

@@ -3,6 +3,7 @@ using SharedClientServer;
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Net;
 using System.Net.Sockets;
 using System.Text;
 
@@ -13,13 +14,30 @@ namespace Server.Models
         private TcpListener listener;
         private List<ServerClient> serverClients;
         public bool Started = false;
+        private static readonly object padlock = new object();
+        private static ServerCommunication instance = null;
 
-        public ServerCommunication(TcpListener listener)
+        private ServerCommunication()
         {
-            this.listener = listener;
+            listener = new TcpListener(IPAddress.Any, 5555);
             serverClients = new List<ServerClient>();
         }
 
+        public static ServerCommunication INSTANCE
+        {
+            get
+            {
+                lock (padlock)
+                {
+                    if (instance == null) {
+                        instance = new ServerCommunication();
+                    }
+
+                }
+                return INSTANCE;
+            }
+        }
+
         public void Start()
         {
             listener.Start();

Server/ViewModels/MainViewModel.cs

@@ -8,6 +8,7 @@ using System.Net;
 using System.Net.Sockets;
 using System.Text;
 using System.Windows.Input;
+using System.Windows.Media;
 
 namespace Server.ViewModels
 {
@@ -16,20 +17,23 @@ namespace Server.ViewModels
         private ServerCommunication serverCommunication;
         public ICommand ServerStartCommand { get; set; }
         public Information InformationModel { get; set; }
+        private MainWindow mainWindow;
 
-        public MainViewModel()
+        public MainViewModel(MainWindow mainWindow)
         {
+            this.mainWindow = mainWindow;
             Debug.WriteLine("init mainviewmodel");
             InformationModel = new Information();
             InformationModel.CanStartServer = true;
             InformationModel.ServerOnline = false;
+            
             this.ServerStartCommand = new RelayCommand(() =>
             {
                 Debug.WriteLine("connect button clicked");
                 if (serverCommunication == null)
                 {
                     Debug.WriteLine("making new server communication");
-                    serverCommunication = new ServerCommunication(new TcpListener(IPAddress.Any,5555));
+                    serverCommunication = ServerCommunication.INSTANCE;
                 }
                 if (!serverCommunication.Started)
                 {

Server/Views/MainWindow.xaml

@@ -8,7 +8,7 @@
         Title="MainWindow" Height="450" Width="800">
     <Grid>
         <Button Content="Start Server" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Command="{Binding ServerStartCommand}" IsEnabled="{Binding InformationModel.CanStartServer}"/>
-        <Label Content="{Binding InformationModel.ServerOnline}" HorizontalAlignment="Left" Margin="169,10,0,0" VerticalAlignment="Top"/>
-        <Label Content="Server Online:" HorizontalAlignment="Left" Margin="80,7,0,0" VerticalAlignment="Top"/>
+        <Label Name="serverStatusLabel" Content="{Binding InformationModel.ServerStatus}" HorizontalAlignment="Left" Margin="169,10,0,0" VerticalAlignment="Top"/>
+        <Label Content="Server Status:" HorizontalAlignment="Left" Margin="80,7,0,0" VerticalAlignment="Top"/>
     </Grid>
 </Window>

Server/Views/MainWindow.xaml.cs

@@ -27,8 +27,9 @@ namespace Server
         {
             
             // use mainviewmodel for the bindings of our methods
-            DataContext = new MainViewModel();
+            DataContext = new MainViewModel(this);
             InitializeComponent();
+            
         }
     }
 }