java - 清空后重新填充数组列表

我目前所拥有的是一款游戏，用户按下精灵，当按下它时，它将添加到他们的分数中，然后将其添加到分数中，以便精灵消失。我遇到的问题是，在将精灵从数组列表中完全删除时，一旦按下它们，我将无法弄清楚如何使其重新出现，我是将它们读取到数组列表中还是将其放在不同的方法？

这是精灵代码：

package cct.mad.lab;
import java.util.Random;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.os.Vibrator;
public class Sprite {

    //x,y position of sprite - initial position (0,50)
    private GameView gameView;
    private Bitmap spritebmp;
    //Width and Height of the Sprite image
    private int bmp_width;
    private int bmp_height;
    // Needed for new random coordinates.
    private Random random = new Random();
    private int x = random.nextInt(200)-1;
    private int y = random.nextInt(200)-1;
    int xSpeed = (random.nextInt(30)-15);
    int ySpeed = (random.nextInt(30)-15);

    public Sprite(GameView gameView) {
        this.gameView=gameView;
        spritebmp = BitmapFactory.decodeResource(gameView.getResources(),
          R.drawable.spritehead);
        this.bmp_width = spritebmp.getWidth();
        this.bmp_height= spritebmp.getHeight();
        //random y coordinate for sprite spawn
        x = gameView.getWidth();
        x = random.nextInt(x);
        y = gameView.getHeight();
        y = random.nextInt(y);
    }

    //update the position of the sprite
    public void update() {
        x = x + xSpeed;
        y = y + ySpeed;
        wrapAround(); //Adjust motion of sprite.
    }

    public void draw(Canvas canvas) {
        //Draw sprite image
        canvas.drawBitmap(spritebmp, x , y, null);
    }

    //y -= gameView.getHeight();//Reset y
    public void wrapAround(){
        //Code to wrap around
        //increment x whilst not off screen
        if (x >= (gameView.getWidth() - 40)){ //if gone off the right sides of screen
            xSpeed = (xSpeed * -1);
        }
        if (x <= -10)
        {
            xSpeed = (xSpeed * -1);
        }

        if (y >= (gameView.getHeight() - 40)){//if gone off the bottom of screen
            ySpeed = (ySpeed * -1);
        }

        if (y <= 0)//if gone off the top of the screen
        {
            ySpeed = (ySpeed * -1);
        }
        xSpeed = (xSpeed * -1);
    }


    /* Checks if the Sprite was touched. */
    public boolean wasItTouched(float ex, float ey) {
        boolean touched = false;
        if ((x <= ex) && (ex < x + bmp_width) &&
                (y <= ey) && (ey < y + bmp_height)) {
            touched = true;
        }
        return touched;
    }//End of wasItTouched
}

这是我的代码，用于实际显示项目和数组列表：

public void surfaceCreated(SurfaceHolder holder) {
    // We can now safely setup the game start the game loop.
    ResetGame();//Set up a new game up - could be called by a 'play again option'
    gameLoopThread = new GameLoopThread(this.getHolder(), this);
    gameLoopThread.running = true;
    gameLoopThread.start();
    mBackgroundImage = Bitmap.createScaledBitmap(mBackgroundImage, getWidth(), getHeight(), true);

    for (int sp =0; spritesArrayList.size() < spNumber; sp++) {
        spritesArrayList.add(sprite = new Sprite(this));
    }
}

我不确定为什么它不起作用

最佳答案

当我必须从对象添加/删除项目时，通常我使用HashMap。

在您的情况下，类似于HashMap<String,Sprite>，因此您可以通过哈希键添加/删除标识它们的项目。

例如

//HashMap<String,Sprite> hashSprite
//add
hashSprite.put("sprite1",new Sprite(this));
//remove
hashSprite.remove("sprite1")

我知道这不是一个真正的答案，但是建议还是值得赞赏的！

关于java - 清空后重新填充数组列表，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/30254799/