private void createMainWindow() {
        frame = new JFrame("Poker Hand Simulator");
        frame.setPreferredSize(new Dimension(800, 600));
        frame.setResizable(false);
        frame.setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
        frame.addWindowListener(new ProgramShutdown(this));

        JPanel mainPanel = new JPanel();
        Border padding = BorderFactory.createEmptyBorder(10, 10, 10, 10);

        mainPanel.setBorder(padding);
        mainPanel.setLayout(null);

        frame.setContentPane(mainPanel);

        container = frame.getContentPane();

        frame.pack();
        frame.setVisible(true);
    }