@@ -0,0 +1,1415 @@
+import java.awt.*;%0Aimport java.awt.event.*;%0Aimport javax.swing.*;%0A%0Apublic class GUI %7B%0A   public static void main(String%5B%5D args) %7B%0A      %0A%09  final CardLayout cardLayout = new CardLayout();%0A      %0A%09  final JFrame frame = new JFrame();%0A      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);%0A      %0A      final Container contentPane = frame.getContentPane();%0A      contentPane.setLayout(cardLayout);%0A%0A      final JPanel mainPanel = new JPanel();%0A      final JPanel customerPanel = new JPanel();%0A      %0A      JButton btnCustomer = new JButton(%22Kund%22);%0A      JButton btnBack = new JButton(%22Tillbaka%22);%0A      btnCustomer.setBounds(175, 75, 150, 50);%0A      btnBack.setBounds(10, 10, 100, 25);%0A      %0A      %0A      contentPane.setPreferredSize(new Dimension(500, 500));%0A      contentPane.add(mainPanel, %22Huvudmeny%22);%0A      contentPane.add(customerPanel, %22Kund%22);%0A      %0A      frame.pack();%0A      frame.setLocationRelativeTo(null);%0A      frame.setResizable(false);%0A      frame.setVisible(true);%0A      %0A      mainPanel.setLayout(null);%0A%0A      mainPanel.add(btnCustomer);%0A      customerPanel.setLayout(null);%0A      customerPanel.add(btnBack);%0A%0A      ActionListener btnListener = new ActionListener() %7B%0A         public void actionPerformed(ActionEvent e) %7B%0A            cardLayout.next(contentPane);%0A         %7D%0A      %7D;%0A%0A      btnCustomer.addActionListener(btnListener);%0A      btnBack.addActionListener(btnListener);%0A%0A   %7D%0A%7D%0A

Create GUI.java