Reload JPanel

Question

I have 2 class files. One contains a JPanel that uses JTabbedPane to add a tab for each of my categories. Then in my other class file, I add the JPanel to my JFrame. So now I have some JMenuItems, the JTabbedPane (from the other class file) and some other JLabels etc...
My question is, if I add a new Category, obvisouly I won't see the new tab until I close out, and reload program. I was wondering what is the best way to solve this problem? I don't believe there are myPanel.reload() or myPanel.refresh() methods. Any ideas?

Answer 1

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ClassCommunication {
  public static void main(String[] args) {
    // Once I create an instance of TabbedComponent here
    TabbedComponent tc = new TabbedComponent();
    JPanel panel = new JPanel();
    panel.setBackground(Color.red);
    // I can call its methods with the instance variable tc
    tc.addNewTab("One", panel);
    JFrame f = new JFrame("Class Communication");
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.getContentPane().add(tc);
    f.pack();
    f.setLocation(400,300);
    f.setVisible(true);
    // after gui is realized...
    panel = new JPanel();
    panel.setBackground(Color.yellow);
    tc.addNewTab("Two", panel);
    panel = new JPanel();
    panel.setBackground(Color.blue);
    tc.addNewTab("Three", panel);
    panel = new JPanel();
    panel.setBackground(Color.green);
    tc.addNewTab("Four", panel);
    System.out.println("tab[2] background color = " +
                        tc.getPane().getBackgroundAt(2) + "\n" +
                       "panel[3] background color = " +
                        tc.getPane().getComponentAt(3).getBackground() + "\n" +
                       "tab[1] title = " + tc.getPane().getTitleAt(1));
class TabbedComponent extends JComponent {
  private JTabbedPane tabbedPane;
  public TabbedComponent() {
    setPreferredSize(new Dimension(400,300));
    tabbedPane = new JTabbedPane();
    setLayout(new BorderLayout());
    add(tabbedPane);
  public void addNewTab(String title, JPanel panel) {
    tabbedPane.addTab(title, panel);
    tabbedPane.validate();               // "refresh", a Container method
  public JTabbedPane getPane() {
    return tabbedPane;
}