Author: Nobuo Tamemasa

Control the width of the combobox popup window.

// File: SteppedComboBoxExample.java
/* (swing1.1) */
//package jp.gr.java_conf.tame.swing.examples;

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

import jp.gr.java_conf.tame.swing.combobox.*;

/**
 * @version 1.0 12/12/98
 */  
public class SteppedComboBoxExample extends JFrame {
  public SteppedComboBoxExample() {
    super("SteppedComboBox Example");  
    
    String[] str = {
      "A",
      "abcdefghijklmnopqrstuvwxyz",
      "ABCDEFGHIJKLMNOPQRSTUVWXYZ",
      "0123456789" 
    };
                  
    SteppedComboBox combo = new SteppedComboBox(str);
    Dimension d = combo.getPreferredSize();
    combo.setPreferredSize(new Dimension(50, d.height));
    combo.setPopupWidth(d.width);
    
    getContentPane().setLayout(new FlowLayout());
    getContentPane().add(combo);
  }

  public static void main (String args[]) {
    SteppedComboBoxExample f = new SteppedComboBoxExample();
    f.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(0);
      }
    });
    f.setSize (300, 100);
    f.show();
  }
}




// File: SteppedComboBox.java
/* (swing1.1) */
package jp.gr.java_conf.tame.swing.combobox;

import java.awt.*;
import java.util.*;
import javax.swing.*;
import javax.swing.plaf.metal.*;
import javax.swing.plaf.basic.*;

/**
 * @version 1.0 12/12/98
 */
class SteppedComboBoxUI extends MetalComboBoxUI {
  protected ComboPopup createPopup() {
    BasicComboPopup popup = new BasicComboPopup( comboBox ) {
        
      public void show() {
        Dimension popupSize = ((SteppedComboBox)comboBox).getPopupSize();
        popupSize.setSize( popupSize.width,
          getPopupHeightForRowCount( comboBox.getMaximumRowCount() ) );
        Rectangle popupBounds = computePopupBounds( 0,
          comboBox.getBounds().height, popupSize.width, popupSize.height);
        scroller.setMaximumSize( popupBounds.getSize() );
        scroller.setPreferredSize( popupBounds.getSize() );
        scroller.setMinimumSize( popupBounds.getSize() );
        list.invalidate();            
        int selectedIndex = comboBox.getSelectedIndex();
        if ( selectedIndex == -1 ) {
          list.clearSelection();
        } else {
          list.setSelectedIndex( selectedIndex );
        }            
        list.ensureIndexIsVisible( list.getSelectedIndex() );
        setLightWeightPopupEnabled( comboBox.isLightWeightPopupEnabled() );

        show( comboBox, popupBounds.x, popupBounds.y );
      }
    };
    popup.getAccessibleContext().setAccessibleParent(comboBox);
    return popup;
  }
}
 
 
public class SteppedComboBox extends JComboBox {
  protected int popupWidth;
  
  public SteppedComboBox(ComboBoxModel aModel) {
    super(aModel);
    setUI(new SteppedComboBoxUI());
    popupWidth = 0;
  }

  public SteppedComboBox(final Object[] items) {
    super(items);
    setUI(new SteppedComboBoxUI());
    popupWidth = 0;
  }
  
  public SteppedComboBox(Vector items) {
    super(items);
    setUI(new SteppedComboBoxUI());
    popupWidth = 0;
  }
  
  
  public void setPopupWidth(int width) {
    popupWidth = width;
  }
  
  public Dimension getPopupSize() {
    Dimension size = getSize();
    if (popupWidth < 1) popupWidth = size.width;
    return new Dimension(popupWidth, size.height);
  }
}
  

Posted On: 7-Jan-1999

internet.commerce

Partner With Us Promotional Golf Laptops GPS Memory Best Price Ram Memory Imprinted Gifts Promote Your Website Calling Cards Promotional Products Logo Design Online Education Online Shopping Car Donations