pushpuzzle.java

贪食蛇小游戏 用j2me编的 用的是ide 大家参考一下下哦

/*
 * @(#)PushPuzzle.java	1.3 03/01/22
 *
 * Copyright (c) 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms
 */

package example.pushpuzzle2;

import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
import example.About;

/**
 * PushPuzzle is the MIDlet that drives the game.  It puts up the
 * screens and handles all the commands that are invoked on each
 * screen.
 */
public class PushPuzzle extends MIDlet implements CommandListener {
    Display display;
    private PushPuzzleCanvas canvas;
    private Score score;
    private Screen scoreScreen;
    private Screen levelScreen;
    private Alert alert;

    private Command undoCommand = new Command("Undo", Command.BACK, 1);
    private Command restartCommand = 
        new Command("Start Over", Command.CANCEL, 21);
    private Command exitCommand =
	    new Command("Exit", Command.EXIT, 60);
    private Command scoresCommand =
	    new Command("Show Scores", Command.SCREEN, 26);
    private Command okCommand = 
	    new Command("OK", Command.OK, 30);
    private Command levelCommand =
	    new Command("Change Level", Command.SCREEN, 24);
    private Command nextCommand =
	    new Command("Next Level", Command.SCREEN, 22);
    private Command prevCommand =
	    new Command("Previous Level", Command.SCREEN, 23);
    private Command aboutCommand = 
	    new Command("About", Command.HELP, 30);
    private Command themeCommand = 
	    new Command("Switch Theme", Command.SCREEN, 25);

    /**
     * Creates new PushPuzzle MIDlet.
     */
    public PushPuzzle() {
        display = Display.getDisplay(this);
        score = new Score();
        canvas = new PushPuzzleCanvas(this, score);
        alert = new Alert("Warning");
        if (!score.open()) {
            System.out.println("Score open failed");
        }

        canvas.init();
        canvas.addCommand(undoCommand);
        canvas.addCommand(scoresCommand);
        canvas.addCommand(restartCommand);
        canvas.addCommand(levelCommand);
        canvas.addCommand(exitCommand);
        canvas.addCommand(nextCommand);
        canvas.addCommand(prevCommand);
        canvas.addCommand(aboutCommand);
        canvas.addCommand(themeCommand);
        canvas.setCommandListener(this);
    }

    /**
     * Start creates the thread to do the timing.
     * It should return immediately to keep the dispatcher
     * from hanging.
     */
    public void startApp() {	
        display.setCurrent(canvas);
    }

    /**
     * Pause signals the thread to stop by clearing the thread field.
     * If stopped before done with the iterations it will
     * be restarted from scratch later.
     */
    public void pauseApp() {
    }

    /**
     * Destroy must cleanup everything.
     * Only objects exist so the GC will do all the cleanup
     * after the last reference is removed.
     */
    public void destroyApp(boolean unconditional) {
        display.setCurrent((Displayable)null);
        canvas.destroy();
        if (score != null)
            score.close();
    }

    /**
     * Respond to a commands issued on any Screen
     */
    public void commandAction(Command c, Displayable s) {
        if (c == undoCommand) {
            canvas.undoMove();
        } else if (c == restartCommand) {
            canvas.restartLevel();
        } else if (c == levelCommand) {
            levelScreen = canvas.getLevelScreen();
            levelScreen.addCommand(okCommand);
            levelScreen.setCommandListener(this);
            display.setCurrent(levelScreen);
        } else if (c == okCommand && s == levelScreen) {

            if (!canvas.gotoLevel()) {
                alert.setString("Could not load level");
                display.setCurrent(alert, canvas);
            } else {
                display.setCurrent(canvas);
            }
        } else if (c == scoresCommand) {
            scoreScreen = canvas.getScoreScreen();
            scoreScreen.addCommand(okCommand);
            scoreScreen.setCommandListener(this);
            display.setCurrent(scoreScreen);
        } else if (c == okCommand && s == scoreScreen) {
            display.setCurrent(canvas);
        } else if (c == exitCommand) {
            destroyApp(false);
            notifyDestroyed();
        } else if (c == List.SELECT_COMMAND && s == canvas) {
            // Solved the level
            scoreScreen = canvas.getScoreScreen();
            scoreScreen.addCommand(okCommand);
            scoreScreen.setCommandListener(this);
            display.setCurrent(scoreScreen);
            
            // Read the next screen.
            canvas.nextLevel(1);
        } else if (c == nextCommand) {
            if (!canvas.nextLevel(1)) {
                alert.setString("Could not load level " +
				    (canvas.getLevel() + 1));
                display.setCurrent(alert, canvas);
            } else {
                display.setCurrent(canvas);
            }
            if (s == canvas) {
                canvas.repaint();
            }
        } else if (c == prevCommand) {
            if (!canvas.nextLevel(-1)) {
                alert.setString("Could not load level " +
				    (canvas.getLevel() - 1));
                display.setCurrent(alert, canvas);
            } else {
                display.setCurrent(canvas);
            }
            if (s == canvas) {
                canvas.repaint();
            }
        } else if (c == aboutCommand) {
            About.showAbout(display);
        } else if (c == themeCommand) {
            canvas.changeTheme();
        }
    }
}