java - 编写太空侵略者代码，无法获得子弹消灭外星人

Question

对于这个可能需要一些努力才能解决的问题，我提前表示歉意。这是一个我已经工作了一段时间的小组项目，所以脚本有点复杂，而且我和我一起工作的另外两个人都是 java 的初学者。不幸的是我的问题是我不知道问题是什么，所以我的问题有点模糊。我将尽我所能向您展示相关的代码，并且任何指示可能存在问题的帮助将不胜感激:)

此类 SpriteAlien 创建一个外星人并具有定义外星人运动的方法。

import javax.swing.JPanel;

public class SpriteAlien extends JPanel{

    public int hPosAlien; // alien's horizontal coordinate
    public int vPosAlien; // alien's vertical coordinate

    public int hPosBullet, vPosBullet;


    public int life; // aliens life, some may have more than one

    int dx = 1; // number of pixels the alien moves horizontally every timer cycle
    int dy = 10; // number of pixels the alien moves down when it hits the boundary
    boolean direction = true; // false - left, true - right
    boolean shoot, defeated = false;

    // constructor
    public SpriteAlien (int horizontalPos, int verticalPos){
        hPosAlien = horizontalPos;
        vPosAlien = verticalPos;
    }


    public void moveAlien()
    {   
        //This creates the alien's movement

        // if the alien has not reached the right wall and is moving right
        if ((hPosAlien <= 740) && (direction == true)) { 
            moveRight();
        }

        // if the alien has reached the right wall and is moving right
        else if ((hPosAlien >= 740) && (direction == true)) { 
            moveDown();
            moveLeft();
            direction = false;
        }

        // if the alien has not reached the right wall and is moving left
        else if ((hPosAlien <= 740) && (hPosAlien >= 0) && (direction == false)) {
            moveLeft();
        }

        // if the alien has reached the left wall and is moving left
        else if ((hPosAlien < 0) && (direction == false)) {
            moveDown();
            moveRight();
            direction = true;
        }           
    }

    // methods used for alien movement
    void moveLeft() {
        hPosAlien -= dx;
    }

    void moveRight() {
        hPosAlien += dx;
    }

    void moveDown() {
        vPosAlien += dy;
    }
}

此类 SpriteArray 创建一个像编队一样一起移动的外星人数组

//创建外星人数组来组成我们的外星人军队 公共(public)类 SpriteArray 扩展 Random{

SpriteAlien[] alienArmy = new SpriteAlien[10]; // an array of alien objects
    int index; // index of the array 
    int x, y; // coordinates of the alien

    // constructor
    SpriteArray(){
        // nested loop to position aliens like 2 dimensional arrays on the screen
        for(int i = 0; i < 2; i++){
            for(int j = 0; j < 5; j++)
            {
                index = i*5 + j; // (0*1 + 0) (0*1 + 1) etc

                x = j*120 + 100; // each column is 120 pixels apart
                y = i*80 + 100; // each row is 80 pixels apart 

                alienArmy[index] = new SpriteAlien(x, y);

            }
        }
    }

这是涉及的主要类，Sprite，也是最有可能出现错误的类，因为这是我编写发射子弹的代码的地方，并且应该让外星人被摧毁。我知道这段代码非常长，所以为了让它更容易，我在最相关的位之前添加了“LOOK HERE LOOK HERE”作为注释:P

import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;
import java.util.TimerTask;

import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

public class Sprite extends JPanel implements ActionListener{

    // GAME ANIMATION
    public int hPosShooter; // shooter's horizontal coordinate
    public int vPosShooter; // shooter's vertical coordinate
    public int hPosBullet; // bullet's horizontal coordinate
    public int vPosBullet = 490; // bullet's vertical coordinate
    public int movementSpeed; // shooter's speed(describe shooter movement)
    public Timer loopTime = new Timer(9, this); // used to loop through movements and repaint
    public Timer generateBullet;
    public boolean started = false; // whether or not the game has started
    public boolean fired = false; // whether or not a shot should exist
    public int numberEnemies = 1; // with more enemies this will need to be edited
    public boolean[] destroyed = new boolean[10]; //Array of boolean variables that tell whether or not the alien with the matching index has been destroyed

    public int shootingIndex;

    // display text information
    PlayerInfo pInfo = new PlayerInfo();
    JLabel scoreLabel = new JLabel("score: " + Integer.toString(pInfo.getPlayerScore()));
    JLabel lifeLabel = new JLabel("lives: " + Integer.toString(pInfo.getPlayerLives()));

    // LOAD IMAGES
    String imageNameShooter; //The shooter
    String imageNameAlien; //The alien
    String imageNameBarrier; //The barrier

    protected BufferedImage imageShooter;
    protected BufferedImage imageAlien;
    protected BufferedImage imageBarrier;


    SpriteArray enemies = new SpriteArray();



//  SpriteBarrier barrier1 = new SpriteBarrier(400, 400);
    SpriteBarrierArray barrier1 = new SpriteBarrierArray(160, 360);
    SpriteBarrierArray barrier2 = new SpriteBarrierArray(360, 360);
    SpriteBarrierArray barrier3 = new SpriteBarrierArray(560, 360);

//  int shootingIndex = enemies.AlienShoot();


    public Sprite (String imageNameShooter, String imageNameAlien, String imageNameBarrier){
        try {
            imageShooter = ImageIO.read(new File(imageNameShooter));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        try {
            imageAlien = ImageIO.read(new File(imageNameAlien));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        try {
            imageBarrier = ImageIO.read(new File(imageNameBarrier));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        scoreLabel.setHorizontalTextPosition(JLabel.RIGHT);
        lifeLabel.setHorizontalTextPosition(JLabel.LEFT);
        add(scoreLabel);
        add(lifeLabel);
    }

    public static void SpriteImage(JFrame frame, JPanel panel) throws IOException
    {          
        frame.add(panel);
    }

    // PAINT SPRITE
    protected void paintComponent(Graphics g)
    {
        super.paintComponent(g);
        g.drawImage(imageShooter, hPosShooter, vPosShooter, null); //Draws the shooter in the correct position

        //Draws bullet
        if (fired)
        {
            g.fillRect (hPosBullet, vPosBullet, 8, 12);
        }

        //Draws the aliens
        for(int i = 0; i < 10 ; i++ ){
            g.drawImage(imageAlien, enemies.alienArmy[i].hPosAlien, enemies.alienArmy[i].vPosAlien, null);
            if(destroyed[i] == false)
            {
                g.fillRect (enemies.alienArmy[i].hPosBullet, enemies.alienArmy[i].vPosBullet, 8, 12);
            }
        }

        //Draw the Barriers
        for(int i = 0; i < 12 ; i++ ){
            g.drawImage(imageBarrier, barrier1.barrier[i].hPosBarrier, barrier1.barrier[i].vPosBarrier, null);
            g.drawImage(imageBarrier, barrier2.barrier[i].hPosBarrier, barrier2.barrier[i].vPosBarrier, null);
            g.drawImage(imageBarrier, barrier3.barrier[i].hPosBarrier, barrier3.barrier[i].vPosBarrier, null);
        }

        loopTime.start(); // refreshes the image to make animation work
    }


    //Makes the enemies drop missiles
    void enemyAttack() {

        generateBullet = new Timer(1000, new ActionListener() {
            public void actionPerformed(ActionEvent e){
                shootingIndex = enemies.AlienShoot();
            }
        });
        generateBullet.start();
    }

    //SHOOTER MOVEMENT MECHANICS
    public void actionPerformed(ActionEvent e)
    {   
        //Conditional only allows movement once game has started
        if (started)
        {
            //This only allows movement to the right if the right border hasn't been reached
            if (hPosShooter < 733 && movementSpeed > 0)
            {
                hPosShooter = hPosShooter + movementSpeed;
            }
            //This only allows movement to the left if the left border hasn't been reached
            if (hPosShooter > 0 && movementSpeed < 0)
            {
                hPosShooter = hPosShooter + movementSpeed;
            }

        }

        //FIRE!! LOOK HERE LOOK HERE LOOK HERE!!!!!
        if (fired)
        {
            vPosBullet = vPosBullet - 6; //Bullet moves upwards
            //If alien is hit... it (SHOULD) be destroyed!
            for(int i = 0; i < 10 ; i++ ){
                if (!(destroyed[i]))
                {
                    if (vPosBullet == (enemies.alienArmy[i].vPosAlien + 20) && hPosBullet > enemies.alienArmy[i].hPosAlien && hPosBullet < (enemies.alienArmy[i].hPosAlien + 50))
                    {
                        destroyed[i] = true;
                        repaint();
                        fired = false;
                        vPosBullet = 490;
                    }
                }
            }
            for(int i=0; i<12; i++)
            {
                if (vPosBullet == barrier3.barrier[i].vPosBarrier && hPosBullet > barrier3.barrier[i].hPosBarrier && hPosBullet < (barrier3.barrier[i].hPosBarrier + 20))
                {
                    fired = false;
                    vPosBullet = 490;
                }
                if (vPosBullet == barrier2.barrier[i].vPosBarrier && hPosBullet > barrier2.barrier[i].hPosBarrier && hPosBullet < (barrier2.barrier[i].hPosBarrier + 20))
                {
                    fired = false;
                    vPosBullet = 490;
                }
                if (vPosBullet == barrier1.barrier[i].vPosBarrier && hPosBullet > barrier1.barrier[i].hPosBarrier && hPosBullet < (barrier1.barrier[i].hPosBarrier + 20))
                {
                    fired = false;
                    vPosBullet = 490;
                }
            }
        }
        //OKAY THE IMPORTANT BIT'S OVER NOW!!!

        //When bullet reaches top of screen 'fired' = false
        if (vPosBullet < 0)
        {
            fired = false;
            vPosBullet = 490;
        }

        //This bit of makes the aliens shoot missiles at the user's 'shooter'
        for(int j = 0; j < 10 ; j++ ){
            enemies.alienArmy[j].moveAlien();
            if(enemies.alienArmy[j].shoot == true)
            {
                if(enemies.alienArmy[j].vPosBullet > 600)
                {
                    enemies.alienArmy[j].shoot = false;
                }
                else
                {
                    enemies.alienArmy[j].vPosBullet += 2;
                }

            }
        }


        //The position is then reset
        repaint();
    }
}

非常感谢您提供的任何帮助!

Answer 1

我不确定，但是

if (vPosBullet == (enemies.alienArmy[i].vPosAlien + 20) && hPosBullet > enemies.alienArmy[i].hPosAlien && hPosBullet < (enemies.alienArmy[i].hPosAlien + 50))

第一次测试中有

vPosBullet == (enemies.alienArmy[i].vPosAlien + 20)

我不确定这个坐标是否准确，应该低于或大于也许。

因为这个:

vPosBullet = vPosBullet - 6; //Bullet moves upwards

也许不是解决方案，但你的代码太长了；P

编辑:

正如@user3659404在评论中所说，将if语句更新为:

if (vPosBullet < (enemies.alienArmy[i].vPosAlien + 20) && vPosBullet > enemies.alienArmy[i].vPosAlien && hPosBullet > enemies.alienArmy[i].hPosAlien && hPosBullet < (enemies.alienArmy[i].hPosAlien + 50))