mygamecanvas.java

一个在手机上非常流行的小游戏

package fly;

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

/**
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2004</p>
 * <p>Company: </p>
 * @author not attributable
 * @version 1.0
 */

public class MyGameCanvas extends GameCanvas
implements Runnable, CommandListener{
  private static MyGameCanvas instance;
  Graphics g;
  boolean running;
  Thread t;
  Command startcmd,exitcmd,restartcmd;
  int keystate;
  boolean keyevent;
  boolean key_up,key_down,key_left,key_right,key_fire;
  private boolean allowinput;
  public int screenwidth;
  public int screenheight;
  boolean gameover;
  //define your variable here
  long gametimeoffset;
  long gametime;
  int bombnum;
  int []bombaward;
  int bombawardtop;
  GameObject plane;
  int planedirection;
  TiledLayer background;
  Bullets bullets;
  GameObject explosion;
  GameObject bomb;
  Image bomb_ico;
  Font fontbig,fontsmall;
  //define your variable end


  protected MyGameCanvas() {
    super(true);
    g=getGraphics();
    running=false;
    t=null;
    addCommand(startcmd=new Command("start",Command.OK,1));
    addCommand(exitcmd=new Command("exit",Command.EXIT,1));
    setCommandListener(this);
    screenwidth=getWidth();
    screenheight=getHeight();

    //put your init once code here
    Image img=ImageTools.getImage("/pic/MyPlaneFrames.png");
    plane=new GameObject(img,24,24);
    planedirection=0;
    img=ImageTools.getImage("/pic/back_water.png");
    int backcolumns=screenwidth/img.getWidth()+1;
    int backrows=screenheight/img.getHeight()+1;
    background=new TiledLayer(backcolumns,backrows,img,img.getWidth(),img.getHeight());
    int x,y;
    for (int i = 0; i < backcolumns*backrows; i++) {
      x=i%backcolumns;
      y=i/backcolumns;
      System.out.println("x="+x+" y="+y);
      background.setCell(x,y,1);
    }
    img=ImageTools.getImage("/pic/bullet.png");
    bullets=new Bullets(img,img.getWidth(),img.getHeight(),20,screenwidth,screenheight);
    img=ImageTools.getImage("/pic/explosion.png");
    explosion=new GameObject(img,32,32);
    bomb_ico=ImageTools.getImage("/pic/bomb_icon.png");
    img=ImageTools.getImage("/pic/b_number.png");
    fontbig=new Font(g,img,10,15,new char[]{'0','1','2','3','4','5','6','7','8','9'});
    img=ImageTools.getImage("/pic/s_number.png");
    fontsmall=new Font(g,img,5,7,new char[]{'0','1','2','3','4','5','6','7','8','9'});
    img=ImageTools.getImage("/pic/bomb.png");
    bomb=new GameObject(img,65,65);
    bombaward=new int[]{0,1,1,1,1,1};
    bombawardtop=bombaward.length-1;
    //put your init once code end
  }
  //private void InitInstance(){ }

  synchronized public static MyGameCanvas getInstance() {
    if (instance == null) {
      instance = new MyGameCanvas();
      System.out.println("new MyGameCanvas");
    }
    return instance;
  }

  public void run(){
    System.out.println("MyGameCanvas run start");
    long st=0,et=0,diff=0;
    int rate=50;//16-17 frame per second
    while(running){
      st=System.currentTimeMillis();
      //put your code here
      //input();
      //gameLogic();
      //your code end
      gameinput();
      gameMain();
      et=System.currentTimeMillis();
      diff=et-st;
      if(diff<rate){
        //System.out.println("Sleep "+(rate-diff));
        try {
          Thread.sleep(rate - diff);
        }
        catch (InterruptedException ex) {}
      }else{
        //System.out.println("rush , and the frame using time: "+diff);
      }
    }
    System.out.println("MyGameCanvas run end");
  }

  public void start(){
      if(!running){
        running=true;
        t=new Thread(this);
        t.start();
      }
  }

  private void gameMain() {
    g.setColor(0,0,0);//clear screen
    g.fillRect(0,0,getWidth(),getHeight());

    background.paint(g);//draw background
    //g.setColor(255,255,255);
    //g.drawString("hello",1,1,g.TOP|g.LEFT);
    if(bomb.alive){
      bomb.moveto(plane.sprite.getX()-20,plane.sprite.getY()-20);
      bomb.paint(g);
      bomb.update();
      bullets.killbullets(plane.sprite,32);
    }
    bullets.paint(g);
    plane.paint(g);
    bullets.refreshBullets(plane.sprite,!gameover && !bomb.alive);
    g.drawImage(bomb_ico,0,screenheight-1,g.BOTTOM|g.LEFT);
    fontbig.drawString(String.valueOf(gametime),screenwidth/2-15,10);
    fontsmall.drawString(String.valueOf(bombnum),bomb_ico.getWidth(),screenheight-fontsmall.height);
    if (gameover) {
      explosion.paint(g);
      explosion.update();
      if(!explosion.alive){
        plane.alive=false;
        g.setColor(255,255,255);
        g.drawString(StringTools.timeOpinion(gametime),5,22,g.LEFT|g.TOP);
        g.drawString("fly 0.1 ver by favo yang",2,100,g.LEFT|g.TOP);
        g.drawString("E-mail : [e-mail]",2,115,g.LEFT|g.TOP);
        g.drawString("simulate from:",2,130,g.LEFT|g.TOP);
        g.drawString("Mr.tony 's <hold on 20sec 1.20> ",2,145,g.LEFT|g.TOP);
        g.drawString("hello tony, just funny.",2,160,g.LEFT|g.TOP);
      }
    }else{
      gametime=(System.currentTimeMillis()-gametimeoffset)/1000;
      int awardindex=(int)gametime/20;
      if(awardindex>bombawardtop)
        awardindex=bombawardtop;
      if(bombaward[awardindex]!=0){
        bombnum+=bombaward[awardindex];
        bombaward[awardindex]=0;
      }
      if (keyevent) {
        if(key_up){
          plane.move(0, -3);
          plane.sprite.setFrame(0);
        }
        if(key_down){
          plane.move(0, 3);
            plane.sprite.setFrame(0);
        }
        if(key_left){
          plane.move( -3, 0);
          plane.sprite.setFrame(1);
        }
        if(key_right){
          plane.move(3, 0);
          plane.sprite.setFrame(2);
        }
        if(key_fire){
          if(!bomb.alive && bombnum>0){//bomb isn't actived and there's enough bomb .
            bomb.reset();
            bomb.alive=true;
            bombnum--;
          }
        }
      }
      else {
        plane.sprite.setFrame(0);
      }

    }


    flushGraphics();
  }

  private void gameInit() {
    gameover=false;
    gametime=0;
    gametimeoffset=System.currentTimeMillis();
    allowinput=true;
    key_up=key_down=key_left=key_right=key_fire=false;
    plane.moveto((screenwidth-plane.sprite.getWidth())/2,
                 (screenheight-plane.sprite.getHeight())/2);
    bullets.initBullets();
    plane.reset();
    explosion.reset();
    explosion.lifetime=3;
    bomb.reset();
    bomb.lifetime=6;
    bomb.alive=false;
    bombnum=3;
    for (int i = 0; i < bombaward.length; i++) {
      bombaward[i]=1;
    }
    bombaward[0]=0;
    printInfo();
  }

  public void stop(){
    if(running){
      running = false;
    }
  }

  private void printInfo(){
    System.out.println("MyGameCanvas printInfo() start:");
    System.out.println("width : "+ getWidth()+ " Height: "+getHeight());
    java.lang.Runtime rt=java.lang.Runtime.getRuntime() ;
    System.out.println("total memory: "+rt.totalMemory());
    System.out.println("free memory: "+rt.freeMemory());
    System.out.println("MyGameCanvas printInfo() end:");
  }

  public void commandAction(Command c, Displayable d) {
    String cmdstr=c.getLabel();
    if(cmdstr.equals("start")){
       gameInit();
       start();
       removeCommand(startcmd);
       addCommand(restartcmd=new Command("restart",Command.OK,1));
    }else if(cmdstr.equals("restart")){
      stop();
      while(t.isAlive());
      gameInit();
      start();
    }else if(cmdstr.equals("exit")){
      stop();
      Navigate.midlet.destroyApp(false);
      Navigate.midlet.notifyDestroyed();
    }
  }

  private void gameinput() {
    if(allowinput){
      keystate=getKeyStates();
      keyevent=false;
      if((keystate & UP_PRESSED)!=0){//up
        key_up=true;keyevent=true;
        //deal your unstop job code here
        planedirection=1;
        //System.out.println("up press");
        //deal your unstop job code end
      }else if((keystate & UP_PRESSED)==0){//release key
        if(key_up==true){
          key_up=false;
          //deal your one press-one job code here
          //System.out.println("up release");
          //deal your one press-one job code end
        }
      }

      if((keystate & DOWN_PRESSED)!=0){//down
        key_down=true;keyevent=true;
        //deal your unstop job code here
        planedirection=2;
        //System.out.println("down press");
        //deal your unstop job code end
      }else if((keystate & DOWN_PRESSED)==0){//release key
        if(key_down==true){
          key_down=false;
          //deal your one press-one job code here
          //System.out.println("down release");
          //deal your one press-one job code end
        }
      }

      if((keystate & LEFT_PRESSED)!=0){//left
        key_left=true;keyevent=true;
        //deal your unstop job code here
        planedirection=3;
        //System.out.println("left press");
        //deal your unstop job code end
      }else if((keystate & LEFT_PRESSED)==0){//release key
        if(key_left==true){
          key_left=false;
          //deal your one press-one job code here
          //System.out.println("left release");
          //deal your one press-one job code end
        }
      }

      if((keystate & RIGHT_PRESSED)!=0){//right
        key_right=true;keyevent=true;
        //deal your unstop job code here
        planedirection=4;
        //System.out.println("right press");
        //deal your unstop job code end
      }else if((keystate & RIGHT_PRESSED)==0){//release key
        if(key_right==true){
          key_right=false;
          //deal your one press-one job code here
          //System.out.println("right release");
          //deal your one press-one job code end
        }
      }

      if((keystate & FIRE_PRESSED)!=0){//fire
        key_fire=true;keyevent=true;
        //deal your unstop job code here
        planedirection=0;
        //System.out.println("fire press");
        //deal your unstop job code end
      }else if((keystate & FIRE_PRESSED)==0){//release key
        if(key_fire==true){
          key_fire=false;
          //deal your one press-one job code here
          //System.out.println("fire release");
          //deal your one press-one job code end
        }
      }
      if(!keyevent){
        //no keyevent here
        //System.out.println("NO KEY press");
        //no keyevent end
      }
    }
  }

  public static void cleanJob(){
    instance=null;
  }


}