我正试图在播放器按下时在屏幕上绘制子弹，但是 在几个子弹后我得到以下错误：致命异常：线程-2 这是子弹和游戏视图的类
public class Bullet {
private int x;
private int y;
private int speed;
private Bitmap bitmap;
public Bullet(Context context,int PositionX,int PositionY) {
Log.v("i am in bullet"," come on!!!");
speed = 10;
x = PositionX;
y = PositionY;
bitmap = BitmapFactory.decodeResource(context.getResources(), R.drawable.flash);
}
public void update() {
//Log.v("i am in update bullet"," come on!!!");
//animating the star horizontally right side
//by increasing x coordinate with player speed
x += 20;
}
public Bitmap getBitmap(){return bitmap;}
public int getX() {
return x;
}
public int getY() {
return y;
}
}
返回
public class GameView extends SurfaceView implements Runnable {
private long fps;
private long timeThisFrame;
volatile boolean playing;
private Thread gameThread = null;
private Player player;
//a screenX holder
int screenX;
int i=0;
//context to be used in onTouchEvent to cause the activity transition from GameAvtivity to MainActivity.
Context context;
//the score holder
int score;
//the high Scores Holder
int highScore[] = new int[4];
//Shared Prefernces to store the High Scores
SharedPreferences sharedPreferences;
//to count the number of Misses
int countMisses;
//indicator that the enemy has just entered the game screen
boolean flag ;
//an indicator if the game is Over
private boolean isGameOver ;
private Paint paint;
private Canvas canvas;
private SurfaceHolder surfaceHolder;
private Enemy enemies;
//created a reference of the class Friend
private Friend friend;
//private Bullet bullet;
private ArrayList<Star> stars = new
ArrayList<Star>();
private ArrayList<Bullet> bullet = new
ArrayList<Bullet>();
//defining a boom object to display blast
private Boom boom;
//the mediaplayer objects to configure the background music
static MediaPlayer gameOnsound;
final MediaPlayer killedEnemysound;
final MediaPlayer gameOversound;
public GameView(Context context, int screenX, int screenY) {
super(context);
player = new Player(context, screenX, screenY);
surfaceHolder = getHolder();
paint = new Paint();
//initializing context
this.context = context;
int starNums = 20;
for (int i = 0; i < starNums; i++) {
Star s = new Star(context,screenX, screenY);
stars.add(s);
}
enemies = new Enemy(context,screenX,screenY);
//initializing boom object
boom = new Boom(context);
//initializing the Friend class object
friend = new Friend(context, screenX, screenY);
//setting the score to 0 initially
score = 0;
//setting the countMisses to 0 initially
countMisses = 0;
this.screenX = screenX;
isGameOver = false;
//initializing shared Preferences
sharedPreferences = context.getSharedPreferences("SHAR_PREF_NAME",Context.MODE_PRIVATE);
//initializing the array high scores with the previous values
highScore[0] = sharedPreferences.getInt("score1",0);
highScore[1] = sharedPreferences.getInt("score2",0);
highScore[2] = sharedPreferences.getInt("score3",0);
highScore[3] = sharedPreferences.getInt("score4",0);
//initializing the media players for the game sounds
gameOnsound = MediaPlayer.create(context,R.raw.gameon);
killedEnemysound = MediaPlayer.create(context,R.raw.killedenemy);
gameOversound = MediaPlayer.create(context,R.raw.gameover);
//starting the music to be played across the game
gameOnsound.start();
}
@Override
public void run() {
while (playing) {
long startFrameTime = System.currentTimeMillis();
synchronized (surfaceHolder) {
update();
draw();
control();
}
timeThisFrame = System.currentTimeMillis() - startFrameTime;
if (timeThisFrame >= 1) {
fps = 1000 / timeThisFrame;
}
}
}
private void update() {
//incrementing score as time passes
score++;
player.update();
//setting boom outside the screen
boom.setX(-250);
boom.setY(-250);
for (Star s : stars) {
s.update(player.getSpeed());
}
for (Bullet b : bullet) {
b.update();
}
//setting the flag true when the enemy just enters the screen
if(enemies.getX()==screenX){
flag = true;
}
enemies.update(player.getSpeed(),getFps());
}
private void draw() {
if (surfaceHolder.getSurface().isValid()) {
canvas = surfaceHolder.lockCanvas();
canvas.drawColor(Color.argb(500,135,206,250));
paint.setColor(Color.WHITE);
paint.setTextSize(20);
for (Star s : stars) {
canvas.drawBitmap(
s.getBitmap(),
s.getX(),
s.getY(),
paint);
}
for (Bullet b : bullet) {
canvas.drawBitmap(
b.getBitmap(),
b.getX(),
b.getY(),
paint);
}
canvas.drawBitmap(
player.getBitmap(),
player.getX(),
player.getY(),
paint);
canvas.drawBitmap( enemies.getBitmap(), enemies.getframeToDraw(), enemies.getwhereToDraw(), null);
//drawing the score on the game screen
paint.setTextSize(30);
canvas.drawText("Score:"+score,100,50,paint);
//drawing boom image
canvas.drawBitmap(
boom.getBitmap(),
boom.getX(),
boom.getY(),
paint
);
//draw game Over when the game is over
if(isGameOver){
paint.setTextSize(150);
paint.setTextAlign(Paint.Align.CENTER);
int yPos=(int) ((canvas.getHeight() / 2) - ((paint.descent() + paint.ascent()) / 2));
canvas.drawText("Game Over",canvas.getWidth()/2,yPos,paint);
}
surfaceHolder.unlockCanvasAndPost(canvas);
}
}
private void control() {
try {
gameThread.sleep(17);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void pause() {
playing = false;
try {
gameThread.join();
} catch (InterruptedException e) {
gameThread.interrupt();
}
}
public void resume() {
playing = true;
gameThread = new Thread(this);
gameThread.start();
}
//stop the music on exit
public static void stopMusic(){
gameOnsound.stop();
}
@Override
public boolean onTouchEvent(MotionEvent motionEvent) {
switch (motionEvent.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_UP:
player.stopBoosting();
break;
case MotionEvent.ACTION_DOWN:
player.setBoosting();
break;
}
//if touch the player
if (player.getDetectCollision().contains((int)motionEvent.getX(), (int)motionEvent.getY())) {
Bullet b = new Bullet(context,player.getX()+player.getDetectCollision().width()
,player.getY()-(player.getDetectCollision().height()/2));
bullet.add(b);
Log.d("test", "touch not inside myEditText");
}
//if the game's over, tappin on game Over screen sends you to MainActivity
if(isGameOver){
if(motionEvent.getAction()==MotionEvent.ACTION_DOWN){
context.startActivity(new Intent(context,MainActivity.class));
}
}
return true;
}
public long getFps(){
return fps;
}
}