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Message:

solution

Posted by jq on October 04, 2001 at 10:55 PM

> Hi,

> I would like to know how to use the KeyListener in the JComboBox.
> You should be able to start typing in an editable JComboBox and everytime a key is typed you should select the entered element or the closest one. (please include example)

> Thanks,

import java.awt.event.*;
import javax.swing.*;
import javax.swing.plaf.basic.*;
public class CustomComboEditor extends BasicComboBoxEditor {
int rowCount;
String[] names;
public CustomComboEditor( final String[] names, final int rowCount ) {
super();
this.names = names;
this.rowCount = rowCount;
editor.addKeyListener( new KeyAdapter() {
public void keyReleased( KeyEvent e ) {
processEvent();
}
});

editor.addActionListener( new ActionListener(){
public void actionPerformed(ActionEvent e) {
processEvent();
}
});

editor.addFocusListener( new FocusAdapter() {
public void focusGained( FocusEvent e) {
((JTextField) e.getComponent()).selectAll();
}
public void focusLost( FocusEvent e) {
processEvent();
}
});
}

void processEvent() {
String wordTyped = editor.getText();
for ( int i = 0; i < rowCount; i++ ) {
if (( (String)names[ i ] ).toUpperCase().startsWith( wordTyped.toUpperCase() ) ) {
editor.selectAll();
editor.setText( (String)names[ i ] );
editor.setSelectionStart( wordTyped.length() );
break;
}
}
}
}

import java.util.*;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.io.File;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class TestFrame extends JFrame
{
public TestFrame(){
JComboBox cmb = new JComboBox();
final JLabel label = new JLabel("test");
JTextField textField = new JTextField();

String[] items = new String[10];
for(int i=0; i<10; i++) {
if(i==9) {
items[i]="ttt";
cmb.addItem("ttt");
}
else {
cmb.addItem("Item"+i);
items[i] = "Item"+i;
}
}

cmb.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent evt){
JComboBox source = (JComboBox)evt.getSource();
int iIdx = source.getSelectedIndex();
label.setText(""+iIdx);
}
});
cmb.setEditor(new CustomComboEditor(items, 10));
cmb.setEditable(true);
this.getContentPane().setLayout(new FlowLayout());
this.getContentPane().add(cmb);
this.getContentPane().add(label);
this.getContentPane().add(textField);

}

public static void main(String argv[]) {
try {
TestFrame tf = new TestFrame();

tf.setSize(new Dimension(200, 200));
tf.setVisible(true);
}
catch (Exception ex) {System.out.println("Exception" + ex);
ex.printStackTrace();}
}
}