added needed javafx modules to build since I'm getting the following message at runtime:

"JavaFX runtime components are missing, and are required to run this application"

build.gradle

@@ -7,7 +7,8 @@ plugins {
 
 javafx {
     version = "11.0.2"
-    modules = ['javafx.controls', 'javafx.fxml', 'javafx.base']
+    modules = ['javafx.controls', 'javafx.fxml', 'javafx.base', 'javafx.scene', 'javafx.collections', 'javafx.beans', 'javafx.event', '' +
+            'javafx.stage']
 }
 
 group 'ch.unibas.dmi.dbis'

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/Client.java

@@ -1,6 +1,8 @@
 package ch.unibas.dmi.dbis.cs108.multiplayer.client;
 
 import ch.unibas.dmi.dbis.cs108.BudaLogConfig;
+import ch.unibas.dmi.dbis.cs108.multiplayer.client.gui.ClientModel;
+import ch.unibas.dmi.dbis.cs108.multiplayer.client.gui.GUI;
 import ch.unibas.dmi.dbis.cs108.multiplayer.client.gui.chat.ChatApp;
 import ch.unibas.dmi.dbis.cs108.multiplayer.helpers.ClientPinger;
 
@@ -19,6 +21,7 @@ import org.apache.logging.log4j.Logger;
 
 
 public class Client {
+
   public static final Logger LOGGER = LogManager.getLogger(Client.class);
   public static final BudaLogConfig l = new BudaLogConfig(LOGGER);
 
@@ -27,8 +30,8 @@ public class Client {
   private BufferedWriter out;
   public ClientPinger clientPinger;
 
-  private BufferedWriter toChatGui;
   private ChatApp chatApp;
+  private GUI chatGUi;
 
   /**
    * Saves the position of the client, gets refreshed everytime the client gets a vote request.
@@ -50,16 +53,20 @@ public class Client {
         } catch (Exception e) {
           systemName = "U.N. Owen";
         }
-        if (systemName == null) systemName = "U.N. Owen";
+        if (systemName == null) {
+          systemName = "U.N. Owen";
+        }
       } else {
         systemName = username;
       }
       sendMsgToServer(Protocol.clientLogin + "$" + systemName);
-
+      this.chatApp = new ChatApp(new ClientModel(systemName, this));
+      this.chatGUi = new GUI(this.chatApp);
       clientPinger = new ClientPinger(this, this.socket);
     } catch (IOException e) {
       e.printStackTrace();
     }
+
   }
 
   /**
@@ -108,15 +115,13 @@ public class Client {
     System.out.println(justMsg);
     System.out.println("Please enter your vote");
 
-
     //LOGGER.debug("just checked next line");
   }
 
 
-
   /**
-   * Starts a thread which listens for incoming chat messages / other messages that the user
-   * has to see
+   * Starts a thread which listens for incoming chat messages / other messages that the user has to
+   * see
    */
   public void chatListener() {
     new Thread(new Runnable() {
@@ -131,7 +136,10 @@ public class Client {
             if (chatMsg != null) {
               //LOGGER.debug("chatMSG recieved from Server: " + chatMsg);
               parse(chatMsg);
-            } else { System.out.println("chatMsg is null"); throw new IOException();}
+            } else {
+              System.out.println("chatMsg is null");
+              throw new IOException();
+            }
           } catch (IOException e) {
             //e.printStackTrace();
             LOGGER.warn("Exception while trying to read message: " + e.getMessage());
@@ -165,6 +173,7 @@ public class Client {
 
   /**
    * parses a received message according to the client protocol.
+   *
    * @param msg the message to be parsed.
    */
   public void parse(String msg) {
@@ -210,6 +219,9 @@ public class Client {
       Thread cP = new Thread(client.clientPinger);
       cP.start();
       client.userInputListener();     //this one blocks.
+      //Start the GUI
+      Thread guiThread = new Thread(client.chatGUi);
+      guiThread.start();
     } catch (UnknownHostException e) {
       System.out.println("Invalid host IP");
     } catch (IOException e) {
@@ -228,6 +240,9 @@ public class Client {
       Thread cP = new Thread(client.clientPinger);
       cP.start();
       client.userInputListener();     //this one blocks.
+
+      Thread guiThread = new Thread(client.chatGUi);
+      guiThread.start();
     } catch (UnknownHostException e) {
       System.out.println("Invalid host IP");
     } catch (IOException e) {
@@ -248,5 +263,6 @@ public class Client {
   }
 
   public void sendToChat(String substring) {
+    chatApp.getChatController().addChatMsgToView(substring);
   }
 }

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/gui/ClientModel.java

@@ -8,6 +8,11 @@ public class ClientModel {
   private Client client;
   private String incomingChatMsg;
 
+  public ClientModel(String username, Client client) {
+    this.username = username;
+    this.client = client;
+  }
+
   //private Number;
 
   public Client getClient() {

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/gui/GUI.java

@@ -0,0 +1,25 @@
+package ch.unibas.dmi.dbis.cs108.multiplayer.client.gui;
+
+import ch.unibas.dmi.dbis.cs108.multiplayer.client.gui.chat.ChatApp;
+import javafx.application.Application;
+
+public class GUI implements Runnable{
+
+  ChatApp chatApp;
+  public GUI (ChatApp chatApp) {
+    this.chatApp = chatApp;
+  }
+  /**
+   * When an object implementing interface {@code Runnable} is used to create a thread, starting the
+   * thread causes the object's {@code run} method to be called in that separately executing
+   * thread.
+   * <p>
+   * The general contract of the method {@code run} is that it may take any action whatsoever.
+   *
+   * @see Thread#run()
+   */
+  @Override
+  public void run() {
+    Application.launch(this.chatApp.getClass());
+  }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/gui/chat/ChatApp.java

@@ -1,14 +1,20 @@
 package ch.unibas.dmi.dbis.cs108.multiplayer.client.gui.chat;
 
 import ch.unibas.dmi.dbis.cs108.multiplayer.client.gui.ClientModel;
+import java.io.BufferedReader;
+import java.io.InputStream;
+import java.io.InputStreamReader;
 import javafx.application.Application;
+import javafx.fxml.FXMLLoader;
+import javafx.scene.Parent;
 import javafx.scene.Scene;
 import javafx.scene.layout.AnchorPane;
 import javafx.stage.Stage;
 
 public class ChatApp extends Application {
   ClientModel clientModel;
-  ChatController chatController;
+  private ChatController chatController;
+
 
   public ChatApp(ClientModel clientModel) {
     this.clientModel = clientModel;
@@ -31,8 +37,8 @@ public class ChatApp extends Application {
   @Override
   public void start(Stage primaryStage) throws Exception {
 
-    ChatApp chatApp = new ChatApp(new ClientModel());
-    AnchorPane root = new AnchorPane(chatController.getChatPaneRoot());
+    //ChatApp chatApp = new ChatApp(new ClientModel());
+    Parent root = FXMLLoader.load(getClass().getResource("splitPaneChatView.fxml"));
     // TODO bin chatController.getChatPaneRoot() border to root border for rezising
     Scene scene = new Scene(root);
     primaryStage.setResizable(true);
@@ -42,4 +48,12 @@ public class ChatApp extends Application {
 
 
   }
+
+  public static void main(String[] args) {
+    launch(args);
+  }
+
+  public ChatController getChatController() {
+    return chatController;
+  }
 }

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/gui/chat/ChatController.java

@@ -5,6 +5,7 @@ import ch.unibas.dmi.dbis.cs108.multiplayer.client.gui.ClientModel;
 import ch.unibas.dmi.dbis.cs108.multiplayer.helpers.Protocol;
 import java.net.URL;
 import java.util.ResourceBundle;
+import javafx.application.Platform;
 import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.SimpleBooleanProperty;
 import javafx.beans.property.SimpleStringProperty;
@@ -69,11 +70,10 @@ public class ChatController implements Initializable {
   @Override
   public void initialize(URL location, ResourceBundle resources) {
 
-
     vBoxChatMessages.getChildren().addListener(new ListChangeListener<Node>() {
       @Override
       public void onChanged(Change<? extends Node> c) {
-        vBoxChatMessages.setMaxHeight(vBoxChatMessages.getMaxHeight()*2);
+        vBoxChatMessages.setMaxHeight(vBoxChatMessages.getMaxHeight() * 2);
       }
     });
 
@@ -92,7 +92,6 @@ public class ChatController implements Initializable {
       }
     });
 
-
     /**
      * Initialize what heppens when the sen button is pressed
      */
@@ -132,7 +131,7 @@ public class ChatController implements Initializable {
       public void changed(ObservableValue<? extends Boolean> observable, Boolean oldValue,
           Boolean newValue) {
         //is true if {@code whisperTargetSelectedField} has content
-        if(!newValue) {
+        if (!newValue) {
           cmd = whisper + "$";
         } else {
           cmd = chatToLobby + "$";
@@ -167,10 +166,21 @@ public class ChatController implements Initializable {
     return chatPaneRoot;
   }
 
+  /**
+   * The client calls this method to foreward a chat message to the chat gui
+   *
+   * @param msg the message to be displayed
+   */
   public void addChatMsgToView(String msg) {
     Label l = new Label(msg);
     l.setBackground(Background.fill(Color.LIGHTSKYBLUE));
     l.setTextFill(Color.BLACK);
+    Platform.runLater(new Runnable() {
+      @Override
+      public void run() {
         vBoxChatMessages.getChildren().add(l);
       }
+    });
+  }
+
 }