呉云峰の部屋

import   java.awt.event.ItemEvent;
import   java.awt.event.ItemListener;
import   java.awt.event.KeyEvent;
import   java.awt.event.KeyListener;
import   java.util.List;
import   java.util.Vector;
import   javax.swing.ComboBoxModel;
import   javax.swing.DefaultComboBoxModel;
import   javax.swing.JComboBox;
import   javax.swing.JFrame;
import   javax.swing.JTextField;
/**
* @author fb
* 带有自动检查功能的CombBox
*/
public   class   JAutoCompleteComboBox   extends   JComboBox   {
private   AutoCompleter   completer;
public   JAutoCompleteComboBox()
{
super();
addCompleter();
}
public   JAutoCompleteComboBox(ComboBoxModel   cm)   {
super(cm);
addCompleter();
}
public   JAutoCompleteComboBox(Object[]   items)   {
super(items);
addCompleter();
}
public   JAutoCompleteComboBox(List   v)   {
super((Vector)   v);
addCompleter();
}
private   void   addCompleter()   {
setEditable(true);
completer   =   new   AutoCompleter(this);
}
public   void   autoComplete(String   str)   {
this.completer.autoComplete(str,str.length());
}
public   String   getText()   {
return   ((JTextField)   getEditor().getEditorComponent()).getText();
}
public   void   setText(String   text)   {
((JTextField)   getEditor().getEditorComponent()).setText(text);
}
public   boolean   containsItem(String   itemString)
{
for   (int   i   =   0;   i   <   this.getModel().getSize();   i++)   {
String   _item   =   ""   +   this.getModel().getElementAt(i);
if   (_item.equals(itemString))
return   true;
}
return   false;
}
/*
* 测试方法
*/
public   static   void   main(String[]   args)
{
JFrame   frame   =   new   JFrame();
Object[]   items   =   new   Object[] {   "abc",   "aab",   "aba",   "hpp",   "pp",   "hlp"   };
//DefaultComboBoxModel   model   =   new   DefaultComboBoxModel();
JComboBox   cmb   =   new   JAutoCompleteComboBox(items);
//                model.addElement("abc");
//                model.addElement("aab");
//                model.addElement("aba");
//                model.addElement("hpp");
//                model.addElement("pp");
//                model.addElement("hlp");
frame.getContentPane().add(cmb);
frame.setSize(400,   80);
frame.setVisible(true);
}
}
/**
*   自动完成器。自动找到最匹配的项目，并排在列表的最前面。
*
*   @author   Turbo   Chen
*/
class   AutoCompleter   implements   KeyListener,   ItemListener   {
private   JComboBox   owner   =   null;
private   JTextField   editor   =   null;
private   ComboBoxModel   model   =   null;
public   AutoCompleter(JComboBox   comboBox)
{
owner   =   comboBox;
editor   =   (JTextField)   comboBox.getEditor().getEditorComponent();
editor.addKeyListener(this);
model   =   comboBox.getModel();
owner.addItemListener(this);
}
public   void   keyTyped(KeyEvent   e)   {   }
public   void   keyPressed(KeyEvent   e)   {   }
public   void   keyReleased(KeyEvent   e)
{
char   ch   =   e.getKeyChar();
if   (ch   ==   KeyEvent.CHAR_UNDEFINED||Character.isISOControl(ch)||ch   ==   KeyEvent.VK_DELETE)
return;
int   caretPosition   =   editor.getCaretPosition();
String   str   =   editor.getText();
if   (str.length()   ==   0)
return;
autoComplete(str,   caretPosition);
}
/**
*   自动完成。根据输入的内容，在列表中找到相似的项目.
*/
protected   void   autoComplete(String   strf,   int   caretPosition)
{
Object[]   opts;
opts   =   getMatchingOptions(strf.substring(0,   caretPosition));
if   (owner   !=   null)   {
model   =   new   DefaultComboBoxModel(opts);
owner.setModel(model);
}
if   (opts.length   >   0)   {
String   str   =   opts[0].toString();
editor.setCaretPosition(caretPosition);
if   (owner   !=   null)   {
try   {
owner.showPopup();
}   catch   (Exception   ex)   {
ex.printStackTrace();
}
}
}
}
/**
*
*   找到相似的项目,   并且将之排列到数组的最前面。
*   @param   str
*   @return   返回所有项目的列表。
*/
protected   Object[]   getMatchingOptions(String   str)
{
List   v   =   new   Vector();
List   v1   =   new   Vector();
for   (int   k   =   0;   k   <   model.getSize();   k++)   {
Object   itemObj   =   model.getElementAt(k);
if   (   itemObj!=null   )   {
String   item   =   itemObj.toString().toLowerCase();
if   (item.startsWith(str.toLowerCase()))
v.add(model.getElementAt(k));
else
v1.add(model.getElementAt(k));
}else
v1.add(model.getElementAt(k));
}
for   (int   i   =   0;   i   <   v1.size();   i++)   {
v.add(v1.get(i));
}
if   (v.isEmpty())
v.add(str);
return   v.toArray();
}
public   void   itemStateChanged(ItemEvent   event)
{
if   (event.getStateChange()   ==   ItemEvent.SELECTED)
{
int   caretPosition   =   editor.getCaretPosition();
if   (caretPosition   !=   -1)   {
try   {
editor.moveCaretPosition(caretPosition);
}   catch   (IllegalArgumentException   ex)   {
ex.printStackTrace();
}
}
}
}
}