Java App - Add, Delete, Reorder elements of the buttons

Hello,

I'm developing a Java application.

I created this interface with MockupScreens. Please look at these pictures.

At first time, there's only one element, the user have to enter informations (title and description) then he starts adding elements as he needs. He can edit element infomrations at any time by clicking on "Element N" Button. He can too delete an element or change the order of these elements ...

Let us put these buttons in a JPanel called btnsUnit, then manipulate it by adding, removing and reodering... So a Grid Layout will be efficient to add each panel after each one ..

Thats why I created a new JPanel which will contain an unknown number of ListbtnsUnit JPanel, I fixed 10 as the max number.

I'm just doing these steps when you reply me. I didn't arrived to add btnsUnit JPanel in ListbtnsUnit JPanel.

import java.awt.BorderLayout;
import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import java.awt.Color;
import java.awt.GridLayout;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JTextField;

public class setupDeviceList extends JFrame {

private JPanel contentPane;

/**
 * Launch the application.
 */
public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
        public void run() {
            try {
                setupDeviceList frame = new setupDeviceList();
                frame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    });
}

/**
 * Create the frame.
 */
public setupDeviceList() {
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setBounds(100, 100, 742, 335);
    contentPane = new JPanel();
    contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
    setContentPane(contentPane);
    contentPane.setLayout(null);

     final JPanel ListbtnsUnit = new JPanel();
    ListbtnsUnit.setBackground(Color.RED);
    ListbtnsUnit.setBounds(55, 56, 243, 191);
    contentPane.add(ListbtnsUnit);
    ListbtnsUnit.setLayout(new GridLayout(10, 0));


    final JButton btnAdd = new JButton("Add");
    btnAdd.setBounds(161, 11, 56, 23);
    btnAdd.setVisible(true);


    btnAdd.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent arg0) {

            final JPanel btnsUnit = new JPanel();
            btnsUnit.setBounds(343, 71, 243, 147);
            contentPane.add(btnsUnit);
            btnsUnit.setBackground(Color.ORANGE);
            btnsUnit.setLayout(null);
            btnsUnit.add(btnAdd);

            ListbtnsUnit.add(btnsUnit);
            ListbtnsUnit.revalidate();
            ListbtnsUnit.repaint();



        }
    });

    }
}