Name: tb29552 Date: 10/08/98


/*

Hi, In the course of trying to find a way to correctly
    shift focus around components using the tab and
    shift-tab combinations I found the following
    problem which I have not seen reported. It occurs
    when mixing heavy and lightweight textfield
    components (TextField and JTextField) and involves
    Events being handled by incorrect components.

    Running the sample code I have provided below will
    create a small frame containing a JTextfield,
    TextField, JTextField, and JButton vertically and
    in that order. The sample code provides
    processMouseEvent, processKeyEvent and
    processFocusEvent methods. By moving the events
    between components and clicking with the mouse on
    these components it is easy to see that for some
    reason the mouse events for the TextField (text2
    variable) are being detected and handled by the
    first JTextField component (text1 variable). This
    is obviously incorrect behaviour.

*/
//import com.sun.java.swing.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

class CFTest extends JFrame {
    JTextField text1;
    TextField text2;
    JTextField text3;
    JButton button1;

    CFTest ()
    {
        // Disable swing focus manager as suggested when mixing
        // lightweight and heavyweight components. Focus Manager
        // should now work as per JDK1.1 AWT Focus Manager.
        DefaultFocusManager.disableSwingFocusManager();

        // Initialise text fields and buttons, overriding
        // processMouse, Keym and Focus events. Consume tab
        // key events to prevent focus shift between components
        text1 = new JTextField() {
            public void processKeyEvent(KeyEvent e)
            {
                System.out.println("Text 1: Key Event");
                if (e.getKeyCode() == KeyEvent.VK_TAB)
                    e.consume();
                else
                    super.processKeyEvent(e);
            }

            public void processFocusEvent(FocusEvent e)
            {
                System.out.println("Text 1: Focus Event");
                super.processFocusEvent(e);
            }

            public void processMouseEvent(MouseEvent e)
            {
                System.out.println("Text 1: Mouse Event");
                super.processMouseEvent(e);
            }
        };
        text2 = new TextField() {
            public void processKeyEvent(KeyEvent e)
            {
                System.out.println("Text 2: Key Event");
                if (e.getKeyCode() == KeyEvent.VK_TAB)
                    e.consume();
                else
                    super.processKeyEvent(e);
            }

            public void processFocusEvent(FocusEvent e)
            {
                System.out.println("Text 2: Focus Event");
                super.processFocusEvent(e);
            }

            public void processMouseEvent(MouseEvent e)
            {
                System.out.println("Text 2: Mouse Event");
                super.processMouseEvent(e);
            }
        };
        button1 = new JButton() {
            public void processKeyEvent(KeyEvent e)
            {
                System.out.println("Button 1: Key Events");
                if (e.getKeyCode() == KeyEvent.VK_TAB)
                    e.consume();
                else
                    super.processKeyEvent(e);
            }

            public void processFocusEvent(FocusEvent e)
            {
                System.out.println("Button 1: Focus Event");
                super.processFocusEvent(e);
            }

            public void processMouseEvent(MouseEvent e)
            {
                System.out.println("Button 1: Mouse Event");
                super.processMouseEvent(e);
            }
        };
        text3 = new JTextField() {
            public void processKeyEvent(KeyEvent e)
            {
                System.out.println("Text 3: Key Events");
                if (e.getKeyCode() == KeyEvent.VK_TAB)
                    e.consume();
                else
                    super.processKeyEvent(e);
            }

            public void processFocusEvent(FocusEvent e)
            {
                System.out.println("Text 3: Focus Event");
                super.processFocusEvent(e);
            }

            public void processMouseEvent(MouseEvent e)
            {
                System.out.println("Text 3: Mouse Event");
                super.processMouseEvent(e);
            }
        };

        // add components to frame
        this.getContentPane().setLayout(new GridLayout(0, 1));
        this.getContentPane().add(text1);
        this.getContentPane().add(text2);
        this.getContentPane().add(text3);
        this.getContentPane().add(button1);

        this.pack();

        // local listener class for detecting exit
        this.addWindowListener(new WindowAdapter()
                               {
            public void windowClosing(WindowEvent e)
            {
                dispose();
                System.exit(1);
            }
        });

        // display frame
        this.show();
    }

    // main method to create and display CFTest frame
    public static void main(String args[])
    {
        CFTest t = new CFTest ();
    }
}

(Review ID: 38069)
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