Name: ea65 Date: 03/23/2000


PopupMenus need to be heavyweight when they extend off the edge
of the their containing windows. The calulation for this is
wrong and considers a window's frame decorations to be part
of the window, when Swing can't write on the frame decorations.
This is most serious when a popup menu is positioned with its
y-origin under the title bar of its parent's frame.

Included is a test program that demonstrates the problem.
Compile and run it. It has textfields that set the x- and
y-coords of a popup menu. Hitting the Test button causes the
popup menu to appear. By default, the coors are (100,-15)
which causes most of the first menu item to be hidden under
the frame's title bar. Another interesting value is (-4, -23)
as this will obscure both the menu's left edge and its first
item.


import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

class SwingPopupMenuBug extends JFrame {
  private JPanel topPanel;
  private JTextField xTF;
  private JTextField yTF;
  public static void main(String args[]) {
    SwingPopupMenuBug x = new SwingPopupMenuBug();
  }
  
  public SwingPopupMenuBug() {
    super("Swing Popup Menu Bug");
    topPanel = new JPanel();
    JLabel xLabel = new JLabel("X: ");
    JLabel yLabel = new JLabel("Y: ");
    xTF = new JTextField("100");
    xTF.setColumns(10);
    yTF = new JTextField("-15");
    yTF.setColumns(10);
    JButton testBtn = new JButton("Test");
    testBtn.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        showPopup();
      }
    });
    JPanel southPanel = new JPanel();
    southPanel.setLayout(new GridBagLayout());
    GridBagConstraints c = new GridBagConstraints();
    
    c.gridx = 0;
    c.gridy = 0;
    southPanel.add(xLabel, c);
    
    c.gridx = 1;
    c.gridy = 0;
    southPanel.add(xTF, c);
    
    c.gridx = 0;
    c.gridy = 1;
    southPanel.add(yLabel, c);
    
    c.gridx = 1;
    c.gridy = 1;
    southPanel.add(yTF, c);
    
    c.gridx = 0;
    c.gridy = 2;
    c.gridwidth = 2;
    southPanel.add(testBtn, c);
    
    topPanel.setBorder(BorderFactory.createEmptyBorder(100, 50, 10, 50));
    topPanel.add(BorderLayout.SOUTH, southPanel);
    
    getContentPane().add(topPanel);
    pack();
   // setSize(400, 400);
    setVisible(true);
  }
  
  public void showPopup() {
    JPopupMenu popup = new JPopupMenu();
    popup.add(new JMenuItem("One"));
    popup.add(new JMenuItem("Two"));
    popup.add(new JMenuItem("Three"));
    try {
      int x = Integer.parseInt(xTF.getText());
      int y = Integer.parseInt(yTF.getText());
      popup.show(topPanel, x, y);
    } catch (Exception e) {
      xTF.setText("100");
      yTF.setText("-15");
    }
  }
}
    

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