Display all events occurring in a window

In this example we shall show you how to display all events occurring in a windows. This is very useful when you want to have full control o events that occur in a Java applications that has many windows to handle. It is a very simple ways to manage the activity on your windows.

To display all the events that occur in a window :

• Create class that extends JPanel
• Use enableEvents to enable the events you want for the window
• Override processMouseEvent mehtod to monitor moouse events
• Override processMouseMotionEvent method to monitor the movement of the mouse pointer in the window
• Override processKeyEvent method to monitor key events
• Override processFocusEvent and processComponentEvent methods to monitor the focus changes and the state of your window
• Use a JFrame to create the new window and add to it the JPanel you’ve created

Let’s take a closer look at the code:

package com.javacodegeeks.snippets.desktop;

import java.awt.AWTEvent;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ComponentEvent;
import java.awt.event.FocusEvent;
import java.awt.event.InputEvent;
import java.awt.event.KeyEvent;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.Vector;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class OccuringEventDisplay extends JPanel {

    public OccuringEventDisplay() {

  this.enableEvents(AWTEvent.MOUSE_EVENT_MASK

    | AWTEvent.MOUSE_MOTION_EVENT_MASK | AWTEvent.KEY_EVENT_MASK

    | AWTEvent.FOCUS_EVENT_MASK | AWTEvent.COMPONENT_EVENT_MASK

    | AWTEvent.WINDOW_EVENT_MASK);

  this.setPreferredSize(new Dimension(500, 400));
    }

    @Override
    public void processMouseEvent(MouseEvent event) {

  String type = null;

  switch (event.getID()) {

case MouseEvent.MOUSE_PRESSED:

    type = "MOUSE_PRESSED";

    break;

case MouseEvent.MOUSE_RELEASED:

    type = "MOUSE_RELEASED";

    break;

case MouseEvent.MOUSE_CLICKED:

    type = "MOUSE_CLICKED";

    break;

case MouseEvent.MOUSE_ENTERED:

    type = "MOUSE_ENTERED";

    break;

case MouseEvent.MOUSE_EXITED:

    type = "MOUSE_EXITED";

    break;

  }

  diplay(mousemods(event) + type + ": [" + event.getX() + "," + event.getY() + "] "

    + "num clicks = " + event.getClickCount()

    + (event.isPopupTrigger() ? "; is popup trigger" : ""));

  if (event.getID() == MouseEvent.MOUSE_ENTERED) {

requestFocus();

  }
    }

    @Override
    public void processMouseMotionEvent(MouseEvent event) {

  String str = null;

  switch (event.getID()) {

case MouseEvent.MOUSE_MOVED:

    str = "MOUSE_MOVED";

    break;

case MouseEvent.MOUSE_DRAGGED:

    str = "MOUSE_DRAGGED";

    break;

  }

  diplay(mousemods(event) + str + ": [" + event.getX() + "," + event.getY() + "] "

    + "num clicks = " + event.getClickCount()

    + (event.isPopupTrigger() ? "; is popup trigger" : ""));
    }

    protected String mousemods(MouseEvent event) {

  int modifs = event.getModifiers();

  String str = "";

  if (event.isShiftDown()) {

str += "Shift ";

  }

  if (event.isControlDown()) {

str += "Ctrl ";

  }

  if ((modifs & InputEvent.BUTTON1_MASK) != 0) {

str += "Button 1 ";

  }

  if ((modifs & InputEvent.BUTTON2_MASK) != 0) {

str += "Button 2 ";

  }

  if ((modifs & InputEvent.BUTTON3_MASK) != 0) {

str += "Button 3 ";

  }

  return str;
    }

    @Override
    public void processKeyEvent(KeyEvent event) {

  String eventtype, mods, code, ch;

  switch (event.getID()) {

case KeyEvent.KEY_PRESSED:

    eventtype = "KEY_PRESSED";

    break;

case KeyEvent.KEY_RELEASED:

    eventtype = "KEY_RELEASED";

    break;

case KeyEvent.KEY_TYPED:

    eventtype = "KEY_TYPED";

    break;

default:

    eventtype = "UNKNOWN";

  }

  mods = KeyEvent.getKeyModifiersText(event.getModifiers());

  if (event.getID() == KeyEvent.KEY_TYPED) {

code = "";

  } else {

code = "Code=" + KeyEvent.getKeyText(event.getKeyCode()) + " ("

  + event.getKeyCode() + ")";

  }

  // Get string and numeric versions of the Unicode character, if any.

  if (event.isActionKey()) {

ch = "";

  } else {

ch = "Character=" + event.getKeyChar() + " (Unicode="

  + ((int) event.getKeyChar()) + ")";

  }

  // Display it all.

  diplay(eventtype + ": " + mods + " " + code + " " + ch);
    }

    @Override
    public void processFocusEvent(FocusEvent event) {

  if (event.getID() == FocusEvent.FOCUS_GAINED) {

diplay("FOCUS_GAINED" + (event.isTemporary() ? " (temporary)" : ""));

  } else {

diplay("FOCUS_LOST" + (event.isTemporary() ? " (temporary)" : ""));

  }
    }

    @Override
    public void processComponentEvent(ComponentEvent event) {

  switch (event.getID()) {

case ComponentEvent.COMPONENT_MOVED:

    diplay("COMPONENT_MOVED");

    break;

case ComponentEvent.COMPONENT_RESIZED:

    diplay("COMPONENT_RESIZED");

    break;

case ComponentEvent.COMPONENT_HIDDEN:

    diplay("COMPONENT_HIDDEN");

    break;

case ComponentEvent.COMPONENT_SHOWN:

    diplay("COMPONENT_SHOWN");

    break;

  }
    }

    public void processWindowEvent(WindowEvent event) {

  switch (event.getID()) {

case WindowEvent.WINDOW_OPENED:

    diplay("WINDOW_OPENED");

    break;

case WindowEvent.WINDOW_CLOSED:

    diplay("WINDOW_CLOSED");

    break;

case WindowEvent.WINDOW_CLOSING:

    diplay("WINDOW_CLOSING");

    break;

case WindowEvent.WINDOW_ICONIFIED:

    diplay("WINDOW_ICONIFIED");

    break;

case WindowEvent.WINDOW_DEICONIFIED:

    diplay("WINDOW_DEICONIFIED");

    break;

case WindowEvent.WINDOW_ACTIVATED:

    diplay("WINDOW_ACTIVATED");

    break;

case WindowEvent.WINDOW_DEACTIVATED:

    diplay("WINDOW_DEACTIVATED");

    break;

  }

  if (event.getID() == WindowEvent.WINDOW_CLOSING) {

diplay("WINDOW_CLOSING event received.");

diplay("Application will exit in 5 seconds");

update(this.getGraphics());

try {

    Thread.sleep(5000);

} catch (InterruptedException ex) {

    ;

}

// Exit now

System.exit(0);

  }
    }

    protected Vector lines = new Vector();

    protected void diplay(String str) {

  if (lines.size() == 20) {

lines.removeElementAt(0);

  }

  lines.addElement(str);

  repaint();
    }

    @Override
    public void paintComponent(Graphics graphic) {

  for (int it = 0; it < lines.size(); it++) {

graphic.drawString((String) lines.elementAt(it), 20, it * 16 + 50);

  }
    }

    @Override
    public boolean isOpaque() {

  return false;
    }

    private static void showUI() {

  JFrame frame = new JFrame();

  frame.addWindowListener(new WindowAdapter() {

@Override

public void windowClosing(WindowEvent e) {

    System.exit(0);

}

  });

  frame.getContentPane().add(new OccuringEventDisplay(), BorderLayout.CENTER);

  frame.setSize(600, 400);

  frame.setVisible(true);
    }

    public static void main(String[] args) {

  //Schedule a job for the event-dispatching thread:

  //creating and showing this application's GUI.

  javax.swing.SwingUtilities.invokeLater(new Runnable() {

@Override

public void run() {

    showUI(); 

}

  });
    }

}

 
This was an example on how to Display all events occurring in a window in Java.