public ChatRoom(String text, Client Client) {
        initComponents();
        this.roomId = text;
        this.setTitle(text);
        this.client = Client;
        int screen_width = Toolkit.getDefaultToolkit().getScreenSize().width;  
        int screen_height = Toolkit.getDefaultToolkit().getScreenSize().height;  
        this.setLocation((screen_width - this.getWidth()) / 2,  
                (screen_height - this.getHeight()) / 2);
        myList.setModel(model);
        usernames.add(client.frame.getTitle().toString());
        model.addElement(client.frame.getTitle().toString() + "                                       ");
        for ( int i = client.onLineUsers.size() - 1; i >= 0; i-- )
        {
            invite.addItem(client.onLineUsers.get(i));
        }
        this.setVisible(true);
    }