Problem with setting preferred size

Question

Why in the following code the preferred size doesn't change ?
import java.awt.*;
import javax.swing.*;
public class MyTest extends JFrame {
     private GridBagLayout gridBagLayout = new GridBagLayout();
     private JPanel panel = new JPanel(gridBagLayout);
     private JScrollPane scrollPane = new JScrollPane(panel);
     private JTable table;
     public MyTest() {
          table = new JTable(2, 3);
          panel.add(table);
          add(scrollPane);
          setDefaultCloseOperation(EXIT_ON_CLOSE);
          pack();
          setVisible(true);
     public static void main(String[] args) {
          MyTest frame = new MyTest();
          frame.scrollPane.setPreferredSize(new Dimension(700, 500));
}

Answer 1

Hi...
The problem in your code is this:MyTest frame = new MyTest();
frame.scrollPane.setPreferredSize(new Dimension(700, 500));Here you give the PreferredSize after create the frame... you have to do this before create the frame...
Try to use like this:import java.awt.*;
import javax.swing.*;
public class MyTest extends JFrame {
     private GridBagLayout gridBagLayout = new GridBagLayout();
     private JScrollPane scrollPane;
     private JTable table;
     public MyTest() {
          table = new JTable(2, 3);
          scrollPane = new JScrollPane(table);
                scrollPane.setPreferredSize(new Dimension(700, 500));
          add(scrollPane);               
          setDefaultCloseOperation(EXIT_ON_CLOSE);
          pack();
          setVisible(true);
     public static void main(String[] args) {
          MyTest frame = new MyTest();          
}Regards...