Java Source - Mouse motion demo.

Một mã nguồn mô tả về MouseEvent and MouseMotionListener Interface khá hay. Đây là môt chương trình giám sát các sự kiện của mouse.

Mã nguồn - Source code

import java.awt.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;

// An AWT GUI program inherits from the top-level container java.awt.Frame
public class MouseMotionDemo extends Frame
implements MouseListener, MouseMotionListener {
// This class acts as MouseListener and MouseMotionListener

// To display the (x, y) coordinates of the mouse-clicked
private TextField tfMouseClickX;
private TextField tfMouseClickY;
// To display the (x, y) coordinates of the current mouse-pointer position
private TextField tfMousePositionX;
private TextField tfMousePositionY;

/**
* Constructor to setup the GUI
*/
public MouseMotionDemo() {
setLayout(new FlowLayout()); // "this" frame sets to FlowLayout

add(new Label("X-Click: "));
tfMouseClickX = new TextField(10);
tfMouseClickX.setEditable(false);
add(tfMouseClickX);
add(new Label("Y-Click: "));
tfMouseClickY = new TextField(10);
tfMouseClickY.setEditable(false);
add(tfMouseClickY);

add(new Label("X-Position: "));
tfMousePositionX = new TextField(10);
tfMousePositionX.setEditable(false);
add(tfMousePositionX);
add(new Label("Y-Position: "));
tfMousePositionY = new TextField(10);
tfMousePositionY.setEditable(false);
add(tfMousePositionY);

addMouseListener(this);
addMouseMotionListener(this);
// "super" frame fires MouseEvent to all its registered MouseListener and MouseMotionListener
// "super" frame adds "this" object as MouseListener and MouseMotionListener

setTitle("MouseMotion Demo"); // "super" Frame sets title
setSize(400, 120); // "super" Frame sets initial size
setVisible(true); // "super" Frame shows
}

/**
* The entry main() method
*/
public static void main(String[] args) {
new MouseMotionDemo(); // Let the constructor do the job
}

/**
* MouseListener handlers
*/
// Called back when a mouse-button has been clicked
@Override
public void mouseClicked(MouseEvent e) {
tfMouseClickX.setText(e.getX() + "");
tfMouseClickY.setText(e.getY() + "");
}

// Not Used, but need to provide an empty body for compilation
@Override
public void mousePressed(MouseEvent e) {
}

@Override
public void mouseReleased(MouseEvent e) {
}

@Override
public void mouseEntered(MouseEvent e) {
}

@Override
public void mouseExited(MouseEvent e) {
}

/**
* MouseMotionEvent handlers
*/
// Called back when the mouse-pointer has been moved
@Override
public void mouseMoved(MouseEvent e) {
tfMousePositionX.setText(e.getX() + "");
tfMousePositionY.setText(e.getY() + "");
}

// Not Used, but need to provide an empty body for compilation
@Override
public void mouseDragged(MouseEvent e) {
}
}

Kết quả - Result

Source: ntu