Pourquoi mon Composite à l'intérieur d'un JScrollPane pas de défilement?

J'ai un JPanel (jaune) placé dans JScrollPane.

Quand je tape du texte dans JTextPane, il redimensionne, mais la barre de défilement verticale est toujours pas active. yelowPanel.getSize() renvoie la même valeur qu'avant.`(Vous pouvez le voir sur redPanel).

Alors, comment puis-je actualiser yellowPanel? Je veux panneau de défilement verticale.
J'ai essayé de:

panelCreating.revalidate();
panelCreating.invalidate();
panelCreating.repaint();

Fonctionne uniquement panelCreating.setPreferredSize(new Dimension(333, 777)); mais je ne sais pas quelle taille à définir. Cela dépend du contenu.

Il y a un petit exemple:

package swingtest;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
public class SwingTest extends JFrame {
public SwingTest() {
initComponents();
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new SwingTest().setVisible(true);
}
});
}
private JPanel panelCenter, panelCreating;
private JScrollPane scrollPaneCreating, scrollPaneCenter;
private JTextPane textPane1, textPane2;
private JButton button1;
private void initComponents() {
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setMinimumSize(new Dimension(300, 300));
panelCreating = new JPanel();
panelCreating.setMinimumSize(new Dimension(160, 200));
panelCreating.setPreferredSize(new Dimension(160, 200));
scrollPaneCreating = new JScrollPane(panelCreating,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, 
JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
textPane1 = new JTextPane();
textPane1.setText("a\na");
textPane2 = new JTextPane();
textPane2.setText("b\nb");
button1 = new JButton("+++");
panelCenter = new JPanel();
panelCenter.setBackground(Color.blue);
scrollPaneCenter = new JScrollPane(panelCenter);
//----------------- Left Panel Init -----------------------
panelCreating.setLayout(new GridBagLayout());
panelCreating.setBackground(Color.ORANGE);
panelCreating.setBorder(BorderFactory.createEmptyBorder(8, 8, 8, 8));
GridBagConstraints c = new GridBagConstraints();
c.insets = new Insets(0, 0, 4, 4);
c.anchor = GridBagConstraints.FIRST_LINE_START;
c.weightx = c.weighty = 0;
c.gridx = 0;
c.gridy = GridBagConstraints.RELATIVE;
c.gridwidth = GridBagConstraints.REMAINDER;
c.gridheight = 1;
c.fill = GridBagConstraints.BOTH;
panelCreating.add(textPane1, c);
button1.addActionListener(new ActionListener() {
int height = 50;
@Override
public void actionPerformed(ActionEvent e) {
textPane1.setText(textPane1.getText() + "\na");
textPane1.setPreferredSize(new Dimension(150, height));
textPane2.setText(textPane2.getText() + "\nb");
textPane2.setPreferredSize(new Dimension(150, height));
height += 30;
panelCreating.revalidate();
panelCreating.repaint();
scrollPaneCreating.revalidate();
}
});
panelCreating.add(button1, c);
panelCreating.add(textPane2, c);
//-------------------------------------------------------
getContentPane().setLayout(new GridBagLayout());
c = new GridBagConstraints();
c.ipadx = c.ipady = 0;
c.insets = new Insets(0, 0, 0, 0);
c.weighty = 0;
c.gridheight = 1;
c.gridx = 0;
c.gridy = 1;
c.gridwidth = 1;
c.weightx = 0;
c.fill = GridBagConstraints.BOTH;
getContentPane().add(scrollPaneCreating, c);
c.gridx = 1;
c.gridy = 1;
c.fill = GridBagConstraints.BOTH;
c.weightx = 1;
c.weighty = 1;
getContentPane().add(scrollPaneCenter, c);
}
}

Panneau jaune utilise également le GridBagLayout.
Désolé pour mon anglais

OriginalL'auteur alaster | 2012-02-07