我现在有一个arraylist，我在其中添加了“blossom”对象（从屏幕顶部掉落）。当花朵和屏幕底部的一个盒子发生碰撞时，我想将花朵从排列列表中移除。然而，我现在做的方式（在blossom类中），我得到了arrayindexoutofbounds异常。有人知道我错在哪里吗？我知道这和我的线程有关，我只是不知道把这个方法放在哪里。（这是在我的Blossom类的“hit”方法中执行的）。
板视图
public BoardView(Context context){
super(context);
scorePaint.setColor(Color.BLACK);
scorePaint.setTextSize(12);
scorePaint.setTypeface(Typeface.MONOSPACE);
//surfaceHolder provides canvas that we draw on
getHolder().addCallback(this);
// controls drawings
thread = new BoardThread(getHolder(),this, blossomArrayList, box_x, box_y,
boxWidth, boxHeight);
timer = new Thread(){
public void run(){
//makes sure the player still has 3 lives left
while(game == false){
uiCallback.sendEmptyMessage(0);
try {
Thread.sleep(2000); // wait two seconds before drawing the next flower
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} //sleep for 2 seconds
}
}
};
timer.start();
//intercepts touch events
setFocusable(true);
}
@Override
public void onDraw(Canvas canvas){
canvas.drawColor(Color.WHITE);
score = "SCORE: " + currentScore;
//note: pay attention to order you draw things
//don't change order or else blossoms will fall
//on top of box, not "into" it.
//display the scoreboard
canvas.drawText(score,240,420,scorePaint);
// uses a synchronized method to prevent concurrent modification
DrawBlossoms(canvas);
canvas.drawBitmap(box, box_x, box_y, null);
}
@Override
public boolean onTouchEvent(MotionEvent event){
//handles movement of box
if(event.getAction() == MotionEvent.ACTION_DOWN){
if(event.getX() > box_x & event.getY() > box_y &
event.getX() < box_x + boxWidth & event.getY() < box_y + boxHeight)
{
mode = true;
}
}
if(event.getAction() == MotionEvent.ACTION_MOVE) {
if(event.getX() > box_x & event.getY() > box_y &
event.getX() < box_x + boxWidth & event.getY() < box_y + boxHeight)
{
mode = true;
}
if(mode == true){
box_x = (int)event.getX();
}
}
if(event.getAction() == MotionEvent.ACTION_UP){
mode = false;
}
invalidate();
return true;
}
@Override
public void surfaceChanged(SurfaceHolder holder,
int format, int width, int height ){
Log.v(TAG, "Surface Changed");
//somehow these don't seem to be working
}
@Override
public void surfaceCreated(SurfaceHolder holder){
thread.startRunning(true);
thread.start();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder){
Log.v(TAG, "Surface Destroyed");
//somehow these don't seem to be working
thread.startRunning(false);
thread.stop();
timer.interrupt();
timer.stop();
}
private Handler uiCallback = new Handler(){
public synchronized void handleMessage(Message msg){
//add a new blossom to the blossom ArrayList!!
blossomArrayList.add(new Blossom(
(BitmapFactory.decodeResource
(getResources(), R.drawable.blossom))));
blossomNum++;
//remove neccesary blossoms from list
Log.v(TAG, "Number of Blossoms =" + blossomNum);
}
};
private synchronized void DrawBlossoms(Canvas c)
{
Canvas canvas = c;
for(Blossom blossom: blossomArrayList) // getting errors here
{
blossom.Draw(canvas);
blossom.hit(box_x,box_y, box_x + boxWidth, box_y + boxHeight, blossomArrayList);
}
}
}
花期班
public Blossom(Bitmap bitmap)
{
blossom = bitmap;
blossomWidth = blossom.getWidth();
blossomHeight = blossom.getHeight();
blossom_x = generator.nextInt(320-blossom.getWidth());
blossomRect = new RectF(blossom_x,blossom_y, blossom_x + blossomWidth, blossom_y + blossomHeight);
}
public Bitmap getBitmap()
{
return blossom;
}
public Boolean hit(int boxLeft, int boxTop, int boxRight,int boxBottom, ArrayList<Blossom> blossomArrayList)
{
if(remove == true)
{
Log.v(TAG, "Remove = true");
blossomArrayList.remove(removeInt);
remove = false;
}
if(blossom_x > boxLeft & blossom_y > boxTop
& blossom_x + blossom.getWidth() < boxRight
& blossom_y + blossom.getHeight() < boxBottom)
{
Log.v(TAG, "Collision Detected");
remove = true;
removeInt = blossomArrayList.indexOf(blossom);
return true;
}
else
{
return false;
}
}
public float getBlossomX()
{
return blossom_x;
}
public float getBlossomY()
{
return blossom_y;
}
public float getBlossomWidth()
{
return blossomWidth;
}
public float getBlossomHeight()
{
return blossomHeight;
}
public void Draw(Canvas canvas)
{
//draws the flower falling
if (hit == false)
{
canvas.drawBitmap(blossom, blossom_x,
blossom_y = blossom_y+5 , null);
}
}
public void UpdatePosition()
{
blossomRect.set(blossom_x, blossom_y, blossom_x + 25, blossom_y + 25);
}
}
板螺纹
public BoardThread(SurfaceHolder holder, BoardView boardView2,
ArrayList<Blossom> blossomArrayList1,
int box_x, int box_y, int boxW, int boxH) {
surfaceHolder = holder;
boardView=boardView2;
blossomArrayList = blossomArrayList1;
boxX = box_x;
boxY = box_y;
boxW = boxWidth;
boxH = boxHeight;
}
public void startRunning(boolean run) {
mrun=run;
}
@Override
public void run() {
super.run();
Canvas canvas;
while (mrun) {
canvas=null;
try {
canvas = surfaceHolder.lockCanvas(null);
synchronized (surfaceHolder) {
//update position
Position(blossomArrayList, boxX, boxY, boxWidth, boxHeight);
// draw flowers
boardView.onDraw(canvas); // and getting errors here - concurrent
}
} finally {
if (canvas != null) {
surfaceHolder.unlockCanvasAndPost(canvas);
}
}
}
}
private synchronized void Position(ArrayList<Blossom> blossomArrayList, int box_x, int box_y,
int boxWidth, int boxHeight)
{
for(Blossom blossom: blossomArrayList)
{
blossom.UpdatePosition();
}
}
}
最佳答案
假设您在blossomArrayList.remove(removeInt);上得到错误，您可以尝试删除对象本身，因为.remove(..)可以接受一个对象参数。
关于android - 从ArrayList中移除项目，ArrayIndexOutOfBounds异常，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/5792917/