Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.Component;
import java.awt.KeyboardFocusManager;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

public class Main {
    public static void main(String[] argv) {
        KeyboardFocusManager.getCurrentKeyboardFocusManager().addPropertyChangeListener(new FocusChangeListener());
    }
}

class FocusChangeListener implements PropertyChangeListener {
    public void propertyChange(PropertyChangeEvent evt) {
        Component oldComp = (Component) evt.getOldValue();
        Component newComp = (Component) evt.getNewValue();

        if ("focusOwner".equals(evt.getPropertyName())) {
            if (oldComp == null) {
                System.out.println(newComp.getName());
            } else {
                System.out.println(oldComp.getName());
            }
        } else if ("focusedWindow".equals(evt.getPropertyName())) {
            if (oldComp == null) {
                System.out.println(newComp.getName());
            } else {
                System.out.println(oldComp.getName());
            }
        }
    }
}