pcombobox.java

更方便的SWING

/*
 * PSwing Utilities -- Nifty Swing Widgets
 * Copyright (C) 2002  Pallas Technology
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 * 
 * Pallas Technology
 * 1170 HOWELL MILL RD NW
 * SUITE 306
 * ATLANTA GEORGIA 30318
 * 
 * PHONE [phone]
 * EMAIL [e-mail]
 * 
 * www.pallastechnology.com
 **************************************************************************
 * $Archive: SwingTools$
 * $FileName: PComboBox.java$
 * $FileID: 3$
 *
 * Last change:
 * $AuthorName: Rob MacGrogan$
 * $Date: 8/1/03 1:22 PM$
 * $VerID: 86$
 * $Comment: Debug array index error when PComboBox contains no items.$
 **************************************************************************/
package com.pallas.swing.pcombobox;

import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Vector;
import javax.swing.ComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JTextField;

/**
 * Title:   $FileName: PComboBox.java$
 * @version $VerNum: 11$
 * @author $AuthorName: Rob MacGrogan$<br><br>
 * 
 * $Description: Nifty Swing combobox that functions like the
 *              standard non-web browser combo box people are used to
 *              seeing.$<br>
 * $KeyWordsOff: $<br><br>
 *
 * Nifty Swing combobox that functions like the standard non-web browser combo box
 * people are used to seeing. User types the viewable string of the item they want
 * to select and the closest match will be selected, instead of the default Java
 * functionality which only looks at the first letter of each string in the list.
 */
public class PComboBox extends JComboBox implements PCombo {

  private Vector itemIndex = new Vector();
  private Hashtable listLocationIndex = new Hashtable();
  private FullWordComboKeySelectionModel mgr = null;
  private boolean allowNewEntries = false;

  /**
   * Constructor for PComboBox.
   * @param aModel
   */
  public PComboBox(ComboBoxModel aModel) {
    super(aModel);
    //initializeComponent();
  }

  /**
   * Constructor for PComboBox.
   * @param items
   */
  public PComboBox(Object[] items) {
    super(items);
    //initializeComponent();
  }

  /**
   * Constructor for PComboBox.
   * @param items
   */
  public PComboBox(Vector items) {
    super(items);
    //initializeComponent();
  }

  /**
   * Constructor for PComboBox.
   */
  public PComboBox() {
    super();
    //initializeComponent();
  }

  public Enumeration getUpperCaseContents(){
    return listLocationIndex.keys();
  }

  /**
   * Must be called after all items have been added to combo box, or after a new
   * item is added. This indexes all items String values for fast
   * searching and matching.<br><br>
   *
   * PComboBox WILL NOT WORK IF YOU DO NOT CALL THIS METHOD.
   */
  public synchronized void buildIndex(){
    ComboBoxModel model = getModel();
    itemIndex = new Vector();
    listLocationIndex = new Hashtable();
    for (int i = 0; i < model.getSize(); i++){
      Object o = model.getElementAt(i);
      itemIndex.add(o);
      listLocationIndex.put(o.toString().toUpperCase(), new Integer(i));
    }
    Collections.sort(itemIndex, new ToStringComparator());
  }

  public boolean containsDisplayString(String s){
    int i = search(s);
    boolean contains = false;
    if (i >= 0){
      contains = true;
    }
    return contains;
  }

  /**
   * Selects the first item in the list where itemInList.equals(item).
   * Returns the itemInList.
   */
  public Object setSelectedItemByValue(Object item){
    //Brute force search for now.
    Iterator itr = itemIndex.iterator();
    Object foundItem = null;
    while(itr.hasNext() && foundItem == null){
      Object o = itr.next();
      if (o.equals(item)){
        foundItem = o;
      }
    }
    setSelectedItem(foundItem);
    return foundItem;
  }


  /**
   * Returns the index of the first item in the list that matches
   * the passed in string. A match is made if the first <code>x</code>
   * letters of the item match the search string, where <code>x</code>
   * is the length of the search string.
   */
  public int search(String search){
    int listLocation = -1;
      
    if (itemIndex.size() > 0){
      String s = search.toUpperCase();
  //System.out.println("[C] search for: " + s);
  
      int iBeginSearchRange = 0;
      int iEndSearchRange = itemIndex.size() - 1;
  
      //First, let's check index 0.
      Object oZ = itemIndex.get(0);
      int compZ = compareStrings(s, oZ.toString());
      if (compZ == 0){
        //Index 0 matches.
        listLocation = 0;
      }
      else{
        while (iEndSearchRange != iBeginSearchRange){
          int iRange = (iEndSearchRange - iBeginSearchRange) + 1;
          int iCheckPoint = iBeginSearchRange + (iRange / 2);
  //System.out.println("[C] begin: " + iBeginSearchRange);
  //System.out.println("[C] end: " + iEndSearchRange);
  //System.out.println("[C] check: " + iCheckPoint);
          Object o = itemIndex.get(iCheckPoint);
  //System.out.println("[C] checking: " + o);
          int comp = compareStrings(s, o.toString());
  //System.out.println("[C] comp: " + comp);
          if (comp == 0){
            //We've got a likely match.
            listLocation = iCheckPoint;
            //This will bump us out of the loop.
            iEndSearchRange = iBeginSearchRange;
          }
          else if (comp == 1){
            //search value must be after checkpoint.
            iBeginSearchRange = iCheckPoint;
          }
          else{
            //search value is before checkpoint.
            iEndSearchRange = iCheckPoint - 1;
          }
        }//end while
      }//end else index 0 does not match.
      if (listLocation != -1){
        listLocation = getBestMatchIndex(s, itemIndex.get(listLocation).toString(), listLocation);
      }
    }
    return listLocation;
  }

  /**
   * Double checks list for an exact match of search.
   */
  private int getBestMatchIndex(String search, String item, int listLocation){
    int bestMatchIndex = -1;
    String searchItem = item.toUpperCase();

    if (search.length() < searchItem.length() &&
        listLocationIndex.containsKey(search)){
      //For now, just look for exact match of search.
      Integer intLoc = (Integer)listLocationIndex.get(search);
      bestMatchIndex = intLoc.intValue();
    }
    else{
      //listLocation is it.
      Integer intLoc = (Integer)listLocationIndex.get(itemIndex.get(listLocation).toString().toUpperCase());
      bestMatchIndex = intLoc.intValue();
    }
    return bestMatchIndex;
  }


  /**
   * Returns -1, 0, or 1
   */
  private int compareStrings(String search, String item){
//System.out.println("[C] item: " + item);
    int comp = 0;
    String sBeginItem = item;
    if (item.length() >= search.length()){
      sBeginItem = item.substring(0, search.length());
    }
    if (sBeginItem.equalsIgnoreCase(search)){
      comp = 0;
    }
    else if (ToStringComparator.firstStringSortsBeforeSecond(search, sBeginItem, false)){
      comp = -1;
    }
    else{
      comp = 1;
    }
    return comp;
  }

  /**
   * Initializes the PComboBox.
   */
  protected void initializeComponent(){
    super.setEditable(true);
    //getEditor();
    mgr = new FullWordComboKeySelectionModel(this);
    setKeySelectionManager(mgr);

    getEditor().getEditorComponent().addFocusListener(new PComboFocusListener(mgr));
  }

  public void updateUI(){
    super.updateUI();
    //Update key selection.
    initializeComponent();
  }


  /**
   * This method does nothing. PComboBox always uses FullWordComboKeySelectionModel.
   */
  public void setKeySelectionManager(JComboBox.KeySelectionManager manager){
  }

  /**
   * This method does nothing. PComboBox is always editable.
   */
  public void setEditable(boolean editable){
    //Do nothing.
  }

  /**
   * Returns the editor component of the PComboBox.
   */
  public JTextField getTextField(){
    return (JTextField)(getEditor().getEditorComponent());
  }


  /**
   * Selects the item with the specified display string. If the
   * display string does not occur in the combo box, nothing happens.
   */
  public void setSelectionByDisplay(String display){
    display = display.toUpperCase();
    Integer index = (Integer)listLocationIndex.get(display);
    if (index != null){
      int iIndex = index.intValue();
      setSelectedIndex(iIndex);
    }
  }

  /**
   * Returns the allowNewEntries.
   * @return boolean
   */
  public boolean isAllowNewEntries() {
    return allowNewEntries;
  }

  /**
   * Sets the allowNewEntries.
   * @param allowNewEntries The allowNewEntries to set
   */
  public void setAllowNewEntries(boolean allowNewEntries) {
    this.allowNewEntries = allowNewEntries;
  }

}