public chatRoomQuestion(java.awt.Frame parent, boolean modal, Client Client) {
        super(parent, modal);
        initComponents();
        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);
        this.setVisible(true);
    }