socanvas.java

塞迪网校J2ME移动应用开发教程的所有源代码.

import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.*;
import java.util.*;
import java.io.*;
import javax.microedition.media.*;
import javax.microedition.media.control.*;
import javax.microedition.rms.*;

public class SOCanvas extends GameCanvas implements Runnable {
  private Random         rand;
  private Display        display;
  private boolean        sleeping;
  private long           frameDelay;
  private LayerManager   layers;
  private Image          splash;
  private Image          background;
  private Image          smallCar;
  private MovingSprite   playerSprite;
  private MovingSprite[] blobboSprite = new MovingSprite[3];
  private MovingSprite[] jellySprite = new MovingSprite[3];
  private MovingSprite[] timmySprite = new MovingSprite[3];
  private MovingSprite[] missileSprite = new MovingSprite[10];
  private Sprite[]       explosionSprite = new Sprite[3];
  private Player         musicPlayer;
  private Player         explosionPlayer;
  private Player         gameoverPlayer;
  private boolean        gameOver;
  private int            score, carsLeft;
  private int[]          hiScores = new int[5];

  public SOCanvas(Display d) {
    super(true);
    display = d;

    // Initialize the random number generator
    rand = new Random();

    // Set the frame rate (30 fps)
    frameDelay = 33;
  }
  
  public void start() {
    // Set the canvas as the current screen
    display.setCurrent(this);

    // Read the high scores
    readHiScores();

    // Initialize the background and small car images
    try {
      splash = Image.createImage("/Splash.png");
      background = Image.createImage("/StarryNight.png");
      smallCar = Image.createImage("/SmallCar.png");
    }
    catch (IOException e) {
      System.err.println("Failed loading images!");
    }

    // Initialize the sprites
    try {
      // Create the player car sprite
      playerSprite = new MovingSprite(Image.createImage("/Car.png"), 0, 0,
        MovingSprite.BA_STOP, this);
      playerSprite.setVisible(false);

      int sequence5[] = { 0, 0, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 4, 4, 3, 3, 2, 2, 1, 1 };
      int sequence3[] = { 0, 0, 0, 1, 1, 1, 2, 2, 2, 1, 1, 1 };
      for (int i = 0; i < 3; i++) {
        // Create the Blobbo alien sprites
        blobboSprite[i] = new MovingSprite(Image.createImage("/Blobbo.png"), 20, 21, 3, 2,
          MovingSprite.BA_BOUNCE, this);
        blobboSprite[i].setFrameSequence(sequence5);
        blobboSprite[i].setVisible(false);

        // Create the Jelly alien sprites
        jellySprite[i] = new MovingSprite(Image.createImage("/Jelly.png"), 21, 21, 1, 4,
          MovingSprite.BA_BOUNCE, this);
        jellySprite[i].setFrameSequence(sequence3);
        jellySprite[i].setVisible(false);

        // Create the Timmy alien sprites
        timmySprite[i] = new MovingSprite(Image.createImage("/Timmy.png"), 21, 11, 5, 0,
          MovingSprite.BA_WRAP, this);
        timmySprite[i].setFrameSequence(sequence3);
        timmySprite[i].setVisible(false);

        // Create the explosion sprites
        explosionSprite[i] = new Sprite(Image.createImage("/Explosion.png"), 21, 21);
        explosionSprite[i].setVisible(false);
      }

      // Create the missile sprites
      for (int i = 0; i < 10; i++) {
        missileSprite[i] = new MovingSprite(Image.createImage("/Missiles.png"), 11, 11, 0, 0,
          MovingSprite.BA_HIDE, this);
        missileSprite[i].setVisible(false);
      }
    }
    catch (IOException e) {
      System.err.println("Failed loading images!");
    }

    // Create the layer manager and add the sprites to it
    layers = new LayerManager();
    layers.append(playerSprite);
    for (int i = 0; i < 3; i++) {
      layers.append(blobboSprite[i]);
      layers.append(jellySprite[i]);
      layers.append(timmySprite[i]);
      layers.append(explosionSprite[i]);
    }
    for (int i = 0; i < 10; i++) {
      layers.append(missileSprite[i]);
    }

    // Initialize the music and wave players
    try {
      InputStream is = getClass().getResourceAsStream("Music.mid");
      musicPlayer = Manager.createPlayer(is, "audio/midi");
      musicPlayer.prefetch();
      musicPlayer.setLoopCount(-1);
      is = getClass().getResourceAsStream("Explosion.wav");
      explosionPlayer = Manager.createPlayer(is, "audio/X-wav");
      explosionPlayer.prefetch();
      is = getClass().getResourceAsStream("GameOver.wav");
      gameoverPlayer = Manager.createPlayer(is, "audio/X-wav");
      gameoverPlayer.prefetch();
    }
    catch (IOException ioe) {
    }
    catch (MediaException me) {
    }

    // Show the splash screen by indicating a game over
    gameOver = true;

    // Start the animation thread
    sleeping = false;
    Thread t = new Thread(this);
    t.start();
  }
  
  public void stop() {
    // Close the music and wave players
    musicPlayer.close();
    explosionPlayer.close();
    gameoverPlayer.close();

    // Stop the animation
    sleeping = true;

    // Write the high scores
    writeHiScores();
  }
  
  public void run() {
    Graphics g = getGraphics();
    
    // The main game loop
    while (!sleeping) {
      update();
      draw(g);
      try {
        Thread.sleep(frameDelay);
      }
      catch (InterruptedException ie) {}
    }
  }

  private void update() {
    // Check to see whether the game is being restarted
    if (gameOver) {
      int keyState = getKeyStates();
      if ((keyState & FIRE_PRESSED) != 0)
        // Start a new game
        newGame();

      // The game is over, so don't update anything
      return;
    }

    // Process user input to move the car and fire missiles
    int keyState = getKeyStates();
    if ((keyState & LEFT_PRESSED) != 0) {
      playerSprite.setXSpeed(-2);
    }
    else if ((keyState & RIGHT_PRESSED) != 0) {
      playerSprite.setXSpeed(4);
    }
    if ((keyState & FIRE_PRESSED) != 0) {
      // Play a fire sound
      try {
        Manager.playTone(ToneControl.C4 + 12, 10, 100);
      }
      catch (Exception e) {
      }

      addMissile(playerSprite);
    }
    playerSprite.update();

    // Update the alien and explosion sprites
    for (int i = 0; i < 3; i++) {
      if (blobboSprite[i].isVisible()) {
        blobboSprite[i].update();
        blobboSprite[i].nextFrame();
      }
      if (jellySprite[i].isVisible()) {
        jellySprite[i].update();
        jellySprite[i].nextFrame();
      }
      if (timmySprite[i].isVisible()) {
        timmySprite[i].update();
        timmySprite[i].nextFrame();
      }
      if (explosionSprite[i].isVisible()) {
        if (explosionSprite[i].getFrame() < 3)
          explosionSprite[i].nextFrame();
        else
          explosionSprite[i].setVisible(false);
      }
    }

    // Check for collisions and update the missile sprites
    for (int i = 0; i < 10; i++) {
      if (missileSprite[i].isVisible()) {
        // Is the missile a player missile?
        if (missileSprite[i].getFrame() == 0) {
          for (int j = 0; j < 3; j++) {
            // Did the missile hit a Blobbo alien?
            if (blobboSprite[j].isVisible())
              if (missileSprite[i].collidesWith(blobboSprite[j], false)) {
                // Play a destruction sound
                try {
                  Manager.playTone(ToneControl.C4 - 6, 100, 100);
                }
                catch (Exception e) {
                }

                // Create an explosion
                addExplosion(blobboSprite[j]);

                // Hide the sprites and update the score
                blobboSprite[j].setVisible(false);
                missileSprite[i].setVisible(false);
                score += 10;
                break;
              }
            // Did the missile hit a Jelly alien?
            if (jellySprite[j].isVisible())
              if (missileSprite[i].collidesWith(jellySprite[j], false)) {
                // Play a destruction sound
                try {
                  Manager.playTone(ToneControl.C4 - 6, 100, 100);
                }
                catch (Exception e) {
                }

                // Create an explosion
                addExplosion(jellySprite[j]);

                // Hide the sprites and update the score
                jellySprite[j].setVisible(false);
                missileSprite[i].setVisible(false);
                score += 15;
                break;
              }
            // Did the missile hit a Timmy alien?
            if (timmySprite[j].isVisible())
              if (missileSprite[i].collidesWith(timmySprite[j], false)) {
                // Play a destruction sound
                try {
                  Manager.playTone(ToneControl.C4 - 6, 100, 100);
                }
                catch (Exception e) {
                }

                // Create an explosion
                addExplosion(timmySprite[j]);

                // Hide the sprites and update the score
                timmySprite[j].setVisible(false);
                missileSprite[i].setVisible(false);
                score += 20;
                break;
              }
          }
        }
        // The missile is an alien missile
        else {
          // Did the missile hit the player car sprite
          if (missileSprite[i].collidesWith(playerSprite, false)) {
            // Play a wave sound for the car getting destroyed
            try {
              explosionPlayer.start();
            }
            catch (MediaException me) {
            }

            // Create an explosion
            addExplosion(playerSprite);

            // Reset the player car sprite
            playerSprite.setPosition(0,
              getHeight() - playerSprite.getHeight() - 10);
            playerSprite.setXSpeed(4);
            playerSprite.setYSpeed(0);

            // Hide the missile sprite
            missileSprite[i].setVisible(false);

            // See whether the game is over
            if (carsLeft-- == 0) {
              // Stop the music
              try {
                musicPlayer.stop();
              }
              catch (MediaException me) {
              }

              // Play a wave sound for the game ending
              try {
                gameoverPlayer.start();
              }