implementing "Enter" short cut key

[Sri Rangan]

How to implement "Enter" short cut key on the OK buttons in my swing components (JPanel and JInternalFrames)
Thanks
Sri

[Rene Liebmann]

I'm shure, there are many ways of doing this. One way is, that your JFrame listens for keys. Everytime "Enter" key is pressed, you can send a message to other listening components (JPanel, JInternalFrame). They can do something, when they catch this event. You may ask now, how do you add the components as a listener to your JFrame. One possibility would be the work with Observer and Observable. An other way would be using PropertyChangedEvent.
The only fact is (as I know), the JFrame is the only component, which knows all key events, no matter which component the focus has.

[Sri Rangan]

I tried to remove the Enter Binding from Key map. It does not work right to me.
Could you post some examples with Observer/Observable?
I dont understand why some simple features are made so complicated to code.Like making a button as a "Default Button" in a Component.
Thanks
Sri

[Rene Liebmann]

This is a small example:
File 1 TestJFrame.java

  
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Observable;
import java.util.Observer;
public class TestJFrame extends JFrame {
  private MyObservable obs = new MyObservable();
  public MyBean pnl = new MyBean();
  public TestJFrame(){
    super("Test Frame");
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
    this.addObserver(pnl);
  }
  public static void main(String[] args){
    TestJFrame tjf = new TestJFrame();
    tjf.setSize(400,400);
    tjf.setVisible(true);
  }
  private void jbInit() throws Exception {
    this.addKeyListener(new java.awt.event.KeyAdapter() {
      public void keyPressed(KeyEvent e) {
        this_keyPressed(e);
      }
    });
    this.getContentPane().add(pnl,BorderLayout.CENTER);
  }
  public void addObserver(Observer o){
    obs.addObserver(o);
  }
  public void deleteObserver(Observer o){
    obs.deleteObserver(o);
  }
  void this_keyPressed(KeyEvent e) {
    if (e.getKeyCode() == KeyEvent.VK_ENTER){
      obs.sendChanged();
      obs.notifyObservers();
    }
  }

}
class MyObservable extends Observable {
  public MyObservable() {
  }
  public void sendChanged(){
    super.setChanged();
  }
}

File 2 MyBean.java

  
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Observable;
import java.util.Observer;
public class MyBean extends JComponent implements Observer{
  BorderLayout borderLayout1 = new BorderLayout();
  JPanel jPanel1 = new JPanel();
  JButton btnOk = new JButton();
  public MyBean(){
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }
  public void update(Observable obs, Object o){
    doEnter();
  }
  private void jbInit() throws Exception {
    this.setLayout(borderLayout1);
    btnOk.setText("OK");
    btnOk.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        btnOk_actionPerformed(e);
      }
    });
    this.add(jPanel1, BorderLayout.CENTER);
    jPanel1.add(btnOk, null);
  }
  void btnOk_actionPerformed(ActionEvent e) {
    doEnter();
  }
  public void doEnter(){
    System.out.println("Enter was pressed");
  }
}

Hope this helps you
Rene

[Jawad Kakar]

hostName is a JTextField, which is listening to ENTER key.

 hostName.addKeyListener(new KeyAdapter(){
      public void keyPressed(KeyEvent e){
        if (e.getKeyCode() == KeyEvent.VK_ENTER) {
         e.consume();
         }
      }
    }); 

hope this will help
Jawad
[ November 07, 2002: Message edited by: Jawad Kakar ]