JFrame validation

Question

Hi all,
I have something that I can't understand. Please help.
My problem is in simple JFrame defined like this :
private JFrame frame = null;
public void runFrame(){
          if (this.frame == null){
               frame = new JFrame();
          frame.setBounds(10,10,900,600);
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          frame.getContentPane().setLayout(null);
          frame.getContentPane().addMouseListener(new MouseAdapter(){
                     public void mousePressed(MouseEvent e){
                    buttonAt(e.getX(), e.getY());
}Then I have in same class, but in other method code like this
     protected void buttonAt(int xxx, int yyy){
          JButton button= new JButton("halo");
          button.setBounds(xx,yy,xxx,yyy);
          button.setVisible(true);
          frame.getContentPane().add(button);
          frame.validate();
     }and my problem is : Why I can see only some buttons created. Sometimes it validates three at once, sometimes two... but why this frame is not validating everytime the validation is called. Any help? Some improovement of this code could be great. Thanks a lot.
Esteban

Answer 1

Here it is...
package test;
import java.awt.Color;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
public class Main {
     protected static JFrame frame;
     protected static int xStart = 0, yStart = 0;
     public static void main(String[] args) {
          SwingUtilities.invokeLater(new Runnable(){
               public void run(){
                    if (frame == null){
                         frame = new JFrame();
                    frame.setBounds(10,10,900,600);
                    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    frame.getContentPane().setLayout(null);
                    frame.getContentPane().addMouseListener(new MouseAdapter(){
                         public void mousePressed(MouseEvent e){
                              xStart = e.getX();
                              yStart = e.getY();
                         public void mouseReleased(MouseEvent e){
                              addButton(e.getX(), e.getY());
                    frame.setVisible(true);
     protected static void addButton(int xEnd, int yEnd){
          JButton button = new JButton("halo");
          button.setBackground(new Color(180,180,255));
          button.setBounds(xStart,yStart,xEnd - xStart,yEnd - yStart);
          button.setVisible(true);
          frame.getContentPane().add(button);
          frame.getContentPane().validate();
}Hope you'll help me now...