类似卫星扫描效果

/*

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

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