@Override public void start(Stage primaryStage) throws Exception { BorderPane root = new BorderPane(); HBox message = new HBox(); userText = new TextField(); userText.setEditable(false); userText.setOnAction( e -> { sendMessage(e.getEventType().toString()); userText.setText(""); }); message.getChildren().add(userText); message.setAlignment(Pos.CENTER); message.setPadding(new Insets(10)); chatWindow = new TextArea(); chatWindow.setPrefSize(300, 150); chatWindow.setVisible(true); root.setCenter(chatWindow); root.setBottom(message); startRunning(); primaryStage.setTitle("Instant Messenger"); primaryStage.setScene(new Scene(root, 300, 275)); primaryStage.show(); }