Repainting components.. Please explain

Question

Greetings.
Still a Swing noob...
Ok, I have been attempting to write a few apps with a Swing front end. Thus far I seem to run into alot of problems just based on the fact that I have little experence with swing. So here is my problem now.
I have created a panel in a Jscroll and on that panel I am trying to dynamicly add other smaller repeatable panels.
(I did have trouble and probably still will have trouble with getting the scrollbars to appear correctly. kinda got it to work by monkeying with the panels prefered size. but thats another story.)
anyhow, When I add more panels to the main panel some of my components on the added panel do not show. for example the text fields do show but the labels dont. I CAN GET them all to show by minimizing window then maxing it. (to me points to a "repaint" issue).
Thinking that this is a painting issue I have tried to read a few books on what is going on here. I cant seem to get a good explainati0on.
At the code level I just prototyped the adding of these panels by adding a button that just simply put another panel onto the panel in the scrollpane. I uses the eventDispatch thread to do this. (not sure if thats good or bad). I also tried to call repaint,revalidate on the panel I add as well as the panel I added the new panel to. This did not work.
My ask for help is really a request for an explanation of the underlying principlies to repainting like when to do it? with what thread? are timers allways used? etc.
I also would greatly appreceate a reference to a strong Swing training section that deals with Swing fundamentals. (MVC, Threads, painting).
Explanations that define my immediate problem will also be recieved with great favor. Perhaps fixing this will lead me into an understaning of the repainting issue.
Thanks B.
I have attempted to read Sam's "JFC UNLEASHED" as well as a few others. Those books might be telling me what I am asking for but I'm not getting it. But it is hard to know where to look for this info when you really are kinda in the weeds on the entire subject of Swing.

Answer 1

try to use revalidate();
the code below does the same ;)
package test;
import java.awt.*;
import java.awt.event.ActionListener;
import javax.swing.*;
* @author Sharathk
public class DynamicComponent implements ActionListener{
private JPanel jPanel;
private JFrame jFrame;
private JButton jButton;
/** Creates a new instance of DynamicComponent */
public DynamicComponent() {
init();
private void init(){
jFrame = new JFrame("Dynamic Component");
Container container = jFrame.getContentPane();
jPanel = new JPanel();
jPanel.setLayout(new GridLayout(3, 3, 5, 5));
jPanel.setBackground(Color.WHITE);
JScrollPane jsp = new JScrollPane(jPanel);
jButton = new JButton("Add Panel");
jButton.addActionListener(this);
container.add(jsp);
container.add(jButton, BorderLayout.SOUTH);
private void display() {
addPanel(Color.gray);
jFrame.setSize(300,300);
jFrame.setVisible(true);
private void addPanel(Color panelColor){
JPanel tempPanel = new JPanel();
tempPanel.setBackground(panelColor);
jPanel.add(tempPanel);
jPanel.revalidate();
public static void main(String s[]) {
DynamicComponent dynamicComponent = new DynamicComponent();
dynamicComponent.display();
public void actionPerformed(java.awt.event.ActionEvent e) {
addPanel(Color.gray);
}