类似卫星扫描效果

核心提示：/*Wireless java 2nd edition Jonathan KnudsenPublisher: APRessISBN: 1590590775 */import javax.microedition.lcdui.*;import javax.microedition.lcdui.game.*;import

/*
Wireless java 2nd edition
Jonathan Knudsen
Publisher: APRess
ISBN: 1590590775
*/

import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.*;
import javax.microedition.midlet.*;

public class SweepGame extends MIDlet {
  public void startApp() {
　  final SweepGameCanvas sweeper = new SweepGameCanvas();
　  sweeper.start();
　 
　  sweeper.addCommand(new Command("Exit", Command.EXIT, 0));
　  sweeper.setCommandListener(new CommandListener() {
　　  public void commandAction(Command c, Displayable s) {
　　　  sweeper.stop();
　　　  notifyDestroyed();
　　  }
　  });
　 
　  Display.getDisplay(this).setCurrent(sweeper);
  }
 
  public void pauseApp() {}

  public void destroyApp(boolean unconditional) {}
}

class SweepGameCanvas extends GameCanvas implements Runnable {
  private boolean mTrUCking;
  private int mTheta;
  private int mBorder;
  private int mDelay;
 
  public SweepGameCanvas() {
　  super(true);
　  mTheta = 0;
　  mBorder = 10;
　  mDelay = 50;
  }
 
  public void start() {
　  mTrucking = true;
　  Thread t = new Thread(this);
　  t.start();
  }
 
  public void stop() {
　  mTrucking = false;
  }
　 
  public void render(Graphics g) {
　  int width = getWidth();
　  int height = getHeight();
　 
　  // Clear the Canvas.
　  g.setGrayScale(255);
　  g.fillRect(0, 0, width - 1, height - 1);
　 
　  int x = mBorder;
　  int y = mBorder;
　  int w = width - mBorder * 2;
　  int h = height - mBorder * 2;
　  for (int i = 0; i < 8; i++) {
　　  g.setGrayScale((8 - i) * 32 - 16);
　　  g.fillArc(x, y, w, h, mTheta + i * 10, 10);
　　  g.fillArc(x, y, w, h, (mTheta + 180) % 360 + i * 10, 10);
　  }
  }
 
  public void run() {
　  Graphics g = getGraphics();
　  while (mTrucking) {
　　  mTheta = (mTheta + 1) % 360;
　　  render(g);
　　  flushGraphics();
　　  try { Thread.sleep(mDelay); }
　　  catch (InterruptedException ie) {}
　  }
  }
}类似卫星扫描效果

（出处：http://www.cncms.com）