Hogwarts School Of Computer Science
From Huben's Wiki
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==The Mystery Of The Curly Braces== | ==The Mystery Of The Curly Braces== | ||
| + | Banner.java | ||
| + | <code> | ||
| + | // This applet displays a message moving horizontally | ||
| + | // across the screen. | ||
| + | |||
| + | import java.awt.*; | ||
| + | import java.awt.event.*; | ||
| + | import javax.swing.*; | ||
| + | |||
| + | public class Banner extends JApplet | ||
| + | implements ActionListener | ||
| + | { | ||
| + | private int xPos, yPos; // hold the coordinates of the banner | ||
| + | |||
| + | public void init() | ||
| + | { | ||
| + | Container c = getContentPane(); | ||
| + | c.setBackground(Color.WHITE); | ||
| + | xPos = c.getWidth(); | ||
| + | yPos = c.getHeight() / 2; | ||
| + | Timer clock = new Timer(30, this); // fires every 30 milliseconds | ||
| + | clock.start(); | ||
| + | } | ||
| + | |||
| + | // Called automatically after a repaint request | ||
| + | public void paint(Graphics g) | ||
| + | { | ||
| + | super.paint(g); | ||
| + | g.drawString("Hello, World!", xPos, yPos); | ||
| + | } | ||
| + | |||
| + | // Called automatically when the timer fires | ||
| + | public void actionPerformed(ActionEvent e) | ||
| + | { | ||
| + | Container c = getContentPane(); | ||
| + | |||
| + | // Adjust the horizontal position of the banner: | ||
| + | xPos--; | ||
| + | if (xPos < -100) | ||
| + | { | ||
| + | xPos = c.getWidth(); | ||
| + | } | ||
| + | |||
| + | // Set the vertical position of the banner: | ||
| + | yPos = c.getHeight() / 2; | ||
| + | |||
| + | repaint(); | ||
| + | } | ||
| + | } | ||
| + | </code> | ||
