private JFrame frame;
private JPanel[] statePanels;
private CardLayout layout;
private JPanel mainPanel;
private JButton button;
private String status;

void initAndShow()
{
    //Init stuff
    mainPanel = new JPanel(layout);
    statePanels = new JPanel[2];
    button = new JButton("Exit");
    status = "Menu";

    button.addActionListener(e -> {
        status = status.equals("Menu") ? "World" : "Menu";
        layout.show(mainPanel, status);
    });

    statePanels[0] = new OutWorldHandler();
    statePanels[1] = new InWorldHandler();

    mainPanel.add(statePanels[0], "Menu");
    mainPanel.add(statePanels[1], "World");

    mainPanel.getInputMap().put(KeyStroke.getKeyStroke('f'), "close");
    mainPanel.getActionMap().put("close", this);

    frame.add(mainPanel);
    frame.add(button, BorderLayout.SOUTH);
}

@Override
public void actionPerformed(ActionEvent e)
{
    System.out.println("hi");
}