Name: dm26566 Date: 10/14/98


/* This program shows a problem in Swing that has been there since before 1.0.2
 * and is still in JDK 1.2fcs-N where mouse events which are going to a JPopup
 * menu are leaked back to the underlaying component.
 *
 * To see this for yourself:
 * - compile and run this program
 * - select (click-drag-release) a part of the text (say the first two lines)
 * - move the mouse cursor down below the text, but still in the JTextArea
 * - display the JPopupMenu by using the right mouse button (click AND HOLD!)
 * - while still holding that button, move the cursor to the top and bottom of the
 * JTextArea
 * you will see that the text in the JTextArea is selected and unselected as the
 * mouse moves up and down, even if the events are also selecting different JMenuItems
 * in the JPopupMenu.
 *
 * If you had just popped up the JPopup with a right mouse click-and-release, you
 * would not see this behavior.
 *
 */

import java.awt.*;
import java.awt.event.*;

import javax.swing.*;

public class jpopup extends JFrame implements MouseListener {
  private JComponent popupFromComponent = null;
  private JPopupMenu popup = null;

  public jpopup() {
      super ("Test Frame");
      addWindowListener( new WindowAdapter() {
          public void windowClosing(WindowEvent e) {
System.exit(0);
}
      });

      // build the text area and put it in the frame....
      JTextArea area = new JTextArea("This\nis\nseveral\nlines\nof\ntest\ntext", 20, 20);
      
      this.getContentPane().setLayout( new BorderLayout());
      this.getContentPane().add(area);

      // This is the action listener for the menu item...
      ActionListener menuItemListener = new ActionListener() {
public void actionPerformed( ActionEvent e) {
System.out.println("The cursor was sitting on Component = " + popupFromComponent);
}
      };

      // define and build the JPopup Menu....
      JMenuItem lookupBug = new JMenuItem("Do the first thing...");
      lookupBug.addActionListener(menuItemListener);

      JMenuItem miSave = new JMenuItem("Do the second thing...");
      miSave.addActionListener(menuItemListener);

      JMenuItem miSaveAll = new JMenuItem("Do the third thing...");
      miSaveAll.addActionListener(menuItemListener);

      JMenuItem miSaveSel = new JMenuItem("Do the fourth thing...");
      miSaveSel.addActionListener(menuItemListener);

      popup = new JPopupMenu();
      popup.add(lookupBug);
      popup.addSeparator();
      popup.add(miSave);
      popup.add(miSaveAll);
      popup.add(miSaveSel);

      // add the popup to the component...
      area.addMouseListener(this);

      // display the frame...
      pack();
      show();
  }
    // MouseListener interface:

    // This is the mouse listener to display the popup and store the component that the
    // mouse was over at "click-time"...
  public void mousePressed(MouseEvent event) {
      if (event.isPopupTrigger()) {
popupFromComponent = (JComponent) event.getSource();
popup.show(popupFromComponent, event.getX(), event.getY());
      }
  }
  public void mouseClicked(MouseEvent event) {
  }
  public void mouseReleased(MouseEvent event) {
  }
  public void mouseEntered(MouseEvent event) {
  }
  public void mouseExited(MouseEvent event) {
  }
  
  public static void main(String[] args) {
      jpopup p = new jpopup();
  }
}
(Review ID: 40475)
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