Name: eiC57698 Date: 02/09/98



 JComboBox popup has painting problems when used with standard AWT
 components.

  Here is test case. Execute it, press down arrow on top combo box to
 activate popup. Popup will be partially hidden by "Serialize" button,
 visible part of popup will appear in the bottom combo box.

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/*
 * Experiments with comboBox
 */

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import com.sun.java.swing.*;
import com.sun.java.swing.organic.*;

public class ComboBoxTest extends JFrame implements
ItemListener, ActionListener {
  // The initial width and height of the frame
  public static int WIDTH = 300;
  public static int HEIGHT = 300;
  
  Button serializeButton=null;
  JComboBox days;

  public ComboBoxTest(String lab) {
    super(lab);
    
    // create each button
    days = new JComboBox( );
    days.addItem( "Sunday" );
    days.addItem( "Monday" );
    days.addItem( "Tuesday");
    days.addItem( "Wednesday");
    days.addItem( "Thursday");
    days.addItem( "Friday");
    days.addItem( "Saturday" );
    days.addItemListener( this );
    days.addActionListener( this );

    JComboBox months = new JComboBox();
    months.addItem( "Jan" );
    months.addItem( "Feb" );
    months.addItem( "Mar" );
    months.addItem( "Apr" );
    months.addItem( "May" );
    months.addItem( "Jun" );
    months.addItem( "Jul" );
    months.addItem( "Aug" );
    months.addItem( "Sep" );
    months.addItem( "Oct" );
    months.addItem( "Nov" );
    months.addItem( "Dec" );

    // Add to buttons for serialization/deserialization
    serializeButton = new Button( "Serialize" );
    serializeButton.addActionListener( this );
    
    // Get contents area
    Container content = getContentPane();
    // Set layout to GridLayout - 2 rows x 1 column
    content.setLayout( new GridLayout( 4, 1 ));
    // add to screen
    content.add( days );
    content.add( serializeButton );
    content.add( months );
  }

  public static void main (String args[]) {
    ComboBoxTest frame = new ComboBoxTest("First Swing Stuff");

    frame.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {System.exit(0);}
      public void mouseExited( WindowEvent e ) { System.out.println( "Mouse ex" );}
    });

    frame.setSize(WIDTH, HEIGHT);
    frame.setVisible(true);
  }

  public void actionPerformed( ActionEvent e ) {
    System.out.println( "actionPerformed " + e.getActionCommand());
    Object obj=e.getSource();
    if ( obj instanceof Button ) {
      String lab=e.getActionCommand();
      if ( lab.equals( "Serialize") ) {
System.out.println( "Serialization of ComboBoxes" );
try {
FileOutputStream f =
new FileOutputStream( "ComboBoxTestComboBoxes.ser" );
ObjectOutput s = new ObjectOutputStream( f );
s.writeObject( "Days combobox" );
s.writeObject( days );
s.flush();
} catch ( Exception exc ) {
System.err.println( "An exception occured while serialize days" +
exc.getMessage());
exc.printStackTrace();
}
      }
    }
  }

  public void itemStateChanged( ItemEvent e ) {
    System.out.println( "itemState " + e.getItem() );
  }
}
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