Re: Scroll bar not showing up

"fiziwig" <fiziwig@yahoo.com> wrote in message
news:1153346451.377395.9760@p79g2000cwp.googlegroups.com...


[snip]

Thanks for the SSCCE. A few extra tips: Remove any fields that aren't being
used by your example (e.g. "String knownFileName" wasn't being used). In
some cases, this will allow you to remove a few more imports.

Anyway, now that I saw what you were trying to do, I could fix it: Add the
JScrollBar to the JPanel instead of the JLayeredPane.

<SSCCE>
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.AdjustmentEvent;
import java.awt.event.AdjustmentListener;

import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
import javax.swing.JScrollBar;

public class Example extends JPanel implements AdjustmentListener {

  static private JFrame parentFrame;

  public JLayeredPane layeredPane;

  private JScrollBar vScrollBar;

  public Example() {
    setLayout(new BorderLayout());

    // Create and set up the layered pane.
    layeredPane = new JLayeredPane();
    layeredPane.setPreferredSize(new Dimension(640, 500));
    layeredPane.setBackground(Color.white);
    layeredPane.setOpaque(true);

    vScrollBar = new JScrollBar(JScrollBar.VERTICAL, 10, 30, 0, 100);
    add(vScrollBar, BorderLayout.EAST);
    vScrollBar.setEnabled(false);
    vScrollBar.addAdjustmentListener(this);

    add(layeredPane, BorderLayout.CENTER);
  }

  // Scroll bar event handlers

  public void adjustmentValueChanged(AdjustmentEvent e) {
    System.out.println("New value=" + e.getValue());
  }

  /**
   * Create the GUI and show it. For thread safety, this method should be
invoked from the event-dispatching
   * thread.
   */
  private static void createAndShowGUI() {
    // Make sure we have nice window decorations.
    JFrame.setDefaultLookAndFeelDecorated(true);

    // Create and set up the window.
    parentFrame = new JFrame("Example");
    parentFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    // Create and set up the content pane.
    JComponent newContentPane = new Example();
    newContentPane.setOpaque(true); // content panes must be opaque
    parentFrame.setContentPane(newContentPane);

    // Display the window.
    parentFrame.pack();
    parentFrame.setVisible(true);
  }

  public static void main(String[] args) {
    // Schedule a job for the event-dispatching thread:
    // creating and showing this application's GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        createAndShowGUI();
      }
    });
  }
}
</SSCCE>

    - Oliver