Adding a KeyListener

Question

hello all,
i was doing this homework, and i came upon a point a cant really do. well here is the code:
package homework;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class Draw1 extends JFrame implements MouseMotionListener
private JRadioButton boldRadio,plainRadio,italicRadio;
private JTextField textField;
private Font boldFont, plainFont, italicFont;
private JComboBox box1;
private String CB[] = {"Red","Green","Text"};
private Color ovalColor= Color.RED;
private String X="";
public Draw1()
    this.addMouseMotionListener(this);
    Container c=this.getContentPane();
    JPanel p= new JPanel(new FlowLayout());
    boldFont=new Font("Serif" ,Font.BOLD,14);
    plainFont=new Font("Serif" ,Font.PLAIN,14);
    italicFont=new Font("Serif" ,Font.ITALIC,14);
    textField= new JTextField();
    textField.setFont( boldFont );
    box1 = new JComboBox(CB);
    box1.setMaximumRowCount(1);
    box1.addItemListener(
        new ItemListener(){
      public void itemStateChanged(ItemEvent event2){
        if(event2.getStateChange() == ItemEvent.SELECTED)
          if(box1.getSelectedIndex() == 0)
            ovalColor= Color.RED;
          else if(box1.getSelectedIndex() == 1)
            ovalColor= Color.GREEN;
          //else if(box1.getSelectedIndex() == 2)
    boldRadio=new JRadioButton("Bold",true);
    plainRadio=new JRadioButton("Plain",false);
    italicRadio=new JRadioButton("Italic",false);
    RadioButtonHandler handler = new RadioButtonHandler();
    boldRadio.addItemListener(handler);
    plainRadio.addItemListener(handler);
    italicRadio.addItemListener(handler);
    ButtonGroup radioGroup=new ButtonGroup();
    radioGroup.add(boldRadio);
    radioGroup.add(plainRadio);
    radioGroup.add(italicRadio);
    p.add(box1);
    p.add(boldRadio);
    p.add(plainRadio);
    p.add(italicRadio);
    c.add(p,BorderLayout.NORTH);
    c.add(textField,BorderLayout.SOUTH);
    c.setBackground(Color.white);
    this.setSize(300,300);
    this.setVisible(true);
  public static void main(String[] args)
    Draw1 draw11 = new Draw1();
  public void mouseDragged(MouseEvent e)
    Graphics g=this.getGraphics();
    g.setColor(ovalColor);
    g.fillOval(e.getX(),e.getY(),20,20);
  public void mouseMoved(MouseEvent e)
    //TODO: implement this java.awt.event.MouseMotionListener method;
  private class RadioButtonHandler implements ItemListener {
    public void itemStateChanged( ItemEvent event )
        if ( event.getSource() == boldRadio )
           textField.setFont( boldFont );
        else if ( event.getSource() == plainRadio )
           textField.setFont( plainFont );
        else if ( event.getSource() == italicRadio )
           textField.setFont( italicFont );
}what i need is to add a keylistener, that would be activated when i select "text" from the combobox, and when this listener is active, anything i type should go into the textfield. even if i dont click the textfield.

Answer 1

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class test extends JFrame implements MouseMotionListener {
  FieldKeyListener fieldKeyListener = new FieldKeyListener();
  private JRadioButton boldRadio,plainRadio,italicRadio;
  private JTextField textField;
  private Font boldFont, plainFont, italicFont;
  private JComboBox box1;
  private String CB[] = {"Red","Green","Text"};
  private Color ovalColor= Color.RED;
  private String X="";
  private boolean keyListenerIsActive = false;
  int count = 0;
  public test() {
    this.addMouseMotionListener(this);
    Container c=this.getContentPane();
    JPanel p= new JPanel(new FlowLayout());
    boldFont=new Font("Serif" ,Font.BOLD,14);
    plainFont=new Font("Serif" ,Font.PLAIN,14);
    italicFont=new Font("Serif" ,Font.ITALIC,14);
    textField= new JTextField();
    textField.setFont( boldFont );
    textField.addKeyListener(fieldKeyListener);
    box1 = new JComboBox(CB);
    box1.setMaximumRowCount(1);
    box1.addItemListener(new ItemListener(){
      public void itemStateChanged(ItemEvent event2){
        //System.out.println("stateChange" +
        //                    event2.getStateChange());
        if(event2.getStateChange() == ItemEvent.SELECTED)
          if(box1.getSelectedIndex() == 0) {
            ovalColor= Color.RED;
            keyListenerIsActive = false;
          else if(box1.getSelectedIndex() == 1) {
            ovalColor= Color.GREEN;
            keyListenerIsActive = false;
          else if(box1.getSelectedIndex() == 2) {
            // toggle the key listener control boolean
            keyListenerIsActive = !keyListenerIsActive;
            textField.requestFocus(true);
            count = 0;
          System.out.println("keyListenerIsActive = " +
                              keyListenerIsActive);
    boldRadio=new JRadioButton("Bold",true);
    plainRadio=new JRadioButton("Plain",false);
    italicRadio=new JRadioButton("Italic",false);
    RadioButtonHandler handler = new RadioButtonHandler();
    boldRadio.addItemListener(handler);
    plainRadio.addItemListener(handler);
    italicRadio.addItemListener(handler);
    ButtonGroup radioGroup=new ButtonGroup();
    radioGroup.add(boldRadio);
    radioGroup.add(plainRadio);
    radioGroup.add(italicRadio);
    p.add(box1);
    p.add(boldRadio);
    p.add(plainRadio);
    p.add(italicRadio);
    c.add(p,BorderLayout.NORTH);
    c.add(textField,BorderLayout.SOUTH);
    c.setBackground(Color.white);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setLocation(400,200);
    this.setSize(300,300);
    this.setVisible(true);
  public void mouseDragged(MouseEvent e)
    Graphics g=this.getGraphics();
    g.setColor(ovalColor);
    g.fillOval(e.getX(),e.getY(),20,20);
  public void mouseMoved(MouseEvent e)
    //TODO: implement this java.awt.event.MouseMotionListener method;
  private class RadioButtonHandler implements ItemListener {
    public void itemStateChanged( ItemEvent event )
      if ( event.getSource() == boldRadio )
        textField.setFont( boldFont );
      else if ( event.getSource() == plainRadio )
        textField.setFont( plainFont );
      else if ( event.getSource() == italicRadio )
        textField.setFont( italicFont );
  class FieldKeyListener implements KeyListener {
    public void keyPressed(KeyEvent e) {
      if(!keyListenerIsActive)
        return;
      System.out.println("keyPressed " + count++);
    public void keyReleased(KeyEvent e) { }
    public void keyTyped(KeyEvent e) { }
  public static void main(String[] args) {
    new test();
}