Java 如何添加显示“升级”的按钮？

我尝试了很多方法在下面的代码中添加一个按钮，该代码运行一个太空入侵者游戏，但没有一个成功。谁能看看有没有解决办法

先谢谢你

import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferStrategy;
import java.util.ArrayList;
import javax.swing.JButton;

import javax.swing.JFrame;
import javax.swing.JPanel;

 public class Game extends Canvas {
 /** Image variables to be drawn */
Image imgLevel;
Image imgAliens;
Image img;
JFrame container;  
private BufferStrategy strategy;
private boolean gameRunning = true;
private ArrayList entities = new ArrayList();
private ArrayList removeList = new ArrayList();
private Entity ship;
private double moveSpeed = 500;
private long lastFire = 0;
private long firingInterval;
private long ExtraFiringInterval = 100;
    private long bombFiringInterval = 500;
private int alienCount;
private String message = "";
private boolean waitingForKeyPress = true;
private boolean leftPressed = false;
private boolean rightPressed = false;
    private boolean upPressed = false;
    private boolean downPressed = false;
private boolean firePressed = false;
    private boolean fireExtraPressed = false;
    private boolean bombFired = false;
private boolean logicRequiredThisLoop = false;
    static int level = 8;
    private int Armour;
    Toolkit tk = Toolkit.getDefaultToolkit();  
            int xSize = ((int) tk.getScreenSize().getWidth());  
            int ySize = ((int) tk.getScreenSize().getHeight());
/**
 * Construct our game and set it running.
 */
public Game() {
        img = Toolkit.getDefaultToolkit().createImage("Bg.gif");
    container = new JFrame("Space Invaders Mod");
            container.setSize(xSize,ySize);  
            container.show();
    JPanel panel = (JPanel) container.getContentPane();
    panel.setSize(xSize, ySize);
    panel.setLayout(null);
            container.setSize(xSize, ySize);
    setBounds(0,0,xSize,ySize);
    panel.add(this);
    setIgnoreRepaint(true);
    container.pack();
    container.setResizable(true);
    container.setVisible(true);
    container.addWindowListener(new WindowAdapter() {
                    @Override
        public void windowClosing(WindowEvent e) {
            System.exit(0);
        }
    });
    addKeyListener(new KeyInputHandler());

    requestFocus();

    createBufferStrategy(2);
    strategy = getBufferStrategy();
            initEntities();
}


/**
 * Start a fresh game, this should clear out any old data and
 * create a new set.
 */
private void startGame() {
    entities.clear();
    initEntities();

    leftPressed = false;
    rightPressed = false;
            upPressed = false;
            downPressed = false;
    firePressed = false;
            fireExtraPressed = false;
            bombFired = false;
            firingInterval = 100;
}

/**
 * Initialise the starting state of the entities (ship and aliens). Each
 * entitiy will be added to the overall list of entities in the game.
 */
private void initEntities() {
    ship = new ShipEntity(this,"sprites/ship.png",370,ySize - 130);
    entities.add(ship);  


    alienCount = 0;
            if (level == 1) {
                Armour = 10;
            for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
            entities.add(alien3);
                            alienCount++;
            }
    }
            }
            if (level == 2) {
                Armour = 20;
            for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
            }
    }
            }
            if (level == 3) {
                Armour = 30;
           for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
            }
    }
                            }

            if (level == 4) {
                Armour = 40;
            for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            Entity alien6 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(30)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
                            entities.add(alien6);
                            alienCount++;
            }
    }
            }
            if (level == 5) {
                Armour = 50;
            for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            Entity alien6 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(30)+row*30);
                            Entity alien7 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(40)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
                            entities.add(alien6);
                            alienCount++;
                            entities.add(alien7);
                            alienCount++;
            }
    }
            }
            if (level == 6) {
                Armour = 60;
            for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            Entity alien6 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(30)+row*30);
                            Entity alien7 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(40)+row*30);
                            Entity alien8 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(50)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
                            entities.add(alien6);
                            alienCount++;
                            entities.add(alien7);
                            alienCount++;
                            entities.add(alien8);
                            alienCount++;
            }
    }
            }
            if (level == 7) {
                Armour = 70;
    for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            Entity alien6 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(30)+row*30);
                            Entity alien7 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(40)+row*30);
                            Entity alien8 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(50)+row*30);
                            Entity alien9 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(60)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
                            entities.add(alien6);
                            alienCount++;
                            entities.add(alien7);
                            alienCount++;
                            entities.add(alien8);
                            alienCount++;
                            entities.add(alien9);
                            alienCount++;
            }
    }
            }
            if (level == 8) {
                Armour = 80;
                for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            Entity alien6 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(30)+row*30);
                            Entity alien7 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(40)+row*30);
                            Entity alien8 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(50)+row*30);
                            Entity alien9 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(60)+row*30);
                            Entity alien10 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(70)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
                            entities.add(alien6);
                            alienCount++;
                            entities.add(alien7);
                            alienCount++;
                            entities.add(alien8);
                            alienCount++;
                            entities.add(alien9);
                            alienCount++;
                            entities.add(alien10);
                            alienCount++;

            }
    }
}
            if (level == 9) {
                Armour = 90;
                ExtraFiringInterval --;
                for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            Entity alien6 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(30)+row*30);
                            Entity alien7 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(40)+row*30);
                            Entity alien8 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(50)+row*30);
                            Entity alien9 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(60)+row*30);
                            Entity alien10 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(70)+row*30);
                            Entity alien11 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(80)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
                            entities.add(alien6);
                            alienCount++;
                            entities.add(alien7);
                            alienCount++;
                            entities.add(alien8);
                            alienCount++;
                            entities.add(alien9);
                            alienCount++;
                            entities.add(alien10);
                            alienCount++;
                            entities.add(alien11);
                            alienCount++;
            }
    }
}
            if (level == 10){
                Armour = 100;
                ExtraFiringInterval --;
                for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            Entity alien6 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(30)+row*30);
                            Entity alien7 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(40)+row*30);
                            Entity alien8 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(50)+row*30);
                            Entity alien9 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(60)+row*30);
                            Entity alien10 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(70)+row*30);
                            Entity alien11 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(80)+row*30);
                            Entity alien12 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(90)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
                            entities.add(alien6);
                            alienCount++;
                            entities.add(alien7);
                            alienCount++;
                            entities.add(alien8);
                            alienCount++;
                            entities.add(alien9);
                            alienCount++;
                            entities.add(alien10);
                            alienCount++;
                            entities.add(alien11);
                            alienCount++;
                            entities.add(alien12);
                            alienCount++;
            }
    }
    }
            if (level == 11){
                Armour = 110;
                for (int row=0;row<1;row++) {
                    for (int x=0;x<25;x++) {
            Entity alien3 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(00)+row*30);
                            Entity alien4 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(10)+row*30);
                            Entity alien5 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(20)+row*30);
                            Entity alien6 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(30)+row*30);
                            Entity alien7 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(40)+row*30);
                            Entity alien8 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(50)+row*30);
                            Entity alien9 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(60)+row*30);
                            Entity alien10 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(70)+row*30);
                            Entity alien11 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(80)+row*30);
                            Entity alien12 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(90)+row*30);
                            Entity alien13 = new AlienEntity(this,"sprites/alien.png",100+(x*50),(100)+row*30);
                            entities.add(alien3);
                            alienCount++;
                            entities.add(alien4);
                            alienCount++;
                            entities.add(alien5);
                            alienCount++;
                            entities.add(alien6);
                            alienCount++;
                            entities.add(alien7);
                            alienCount++;
                            entities.add(alien8);
                            alienCount++;
                            entities.add(alien9);
                            alienCount++;
                            entities.add(alien10);
                            alienCount++;
                            entities.add(alien11);
                            alienCount++;
                            entities.add(alien12);
                            alienCount++;
                            entities.add(alien13);
                            alienCount++;
            }
    }
            }
    }

public void updateLogic() {
    logicRequiredThisLoop = true;
}


public void removeEntity(Entity entity) {
    removeList.add(entity);
}


public void notifyDeath() {
    message = "Oh no! They got you, try again?";
    waitingForKeyPress = true;
            level = 0;
}


public void notifyWin() {
    message = "Well done! You beat level "+level;
    waitingForKeyPress = true;
            if (level == 10){
                message = "Well done! You actually beat level 10. Good luck!!";
            }
}


public void notifyAlienKilled() {
    // reduce the alient count, if there are none left, the player has won!
    alienCount = alienCount-1;
            ShotEntity.death = false;
            ShotEntityExtra.death = false;


    if (alienCount == 0) {
        notifyWin();
    }

    // if there are still some aliens left then they all need to get faster, so
    // speed up all the existing aliens
    for (int i=0;i<entities.size();i++) {
        Entity entity = (Entity) entities.get(i);

        if (entity instanceof AlienEntity) {
            // speed up by 2%
            entity.setHorizontalMovement(entity.getHorizontalMovement() * 1.02);
        }
    }
}


public void tryToFire() {

    if (System.currentTimeMillis() - lastFire < firingInterval) {
        return;
    }
            if (level > 6) {

    lastFire = System.currentTimeMillis();
    ShotEntity shot2 = new ShotEntity(this,"sprites/shot.png",ship.getX()+70,ship.getY()-30);
    entities.add(shot2);

    lastFire = System.currentTimeMillis();
    ShotEntity shot3 = new ShotEntity(this,"sprites/shot.png",ship.getX()-30,ship.getY()-30);
    entities.add(shot3);
            }
            if (level > 7){
                lastFire = System.currentTimeMillis();
    ShotEntity shot2 = new ShotEntity(this,"sprites/shot.png",ship.getX()+90,ship.getY()-30);
    entities.add(shot2);
            // if we waited long enough, create the shot entity, and record the time.
    lastFire = System.currentTimeMillis();
    ShotEntity shot3 = new ShotEntity(this,"sprites/shot.png",ship.getX()-50,ship.getY()-30);
    entities.add(shot3);
            }

    // if we waited long enough, create the shot entity, and record the time.
    lastFire = System.currentTimeMillis();
    ShotEntity shot = new ShotEntity(this,"sprites/shot.png",ship.getX()+20,ship.getY()-30);
    entities.add(shot);
            if (level > 3){
                // if we waited long enough, create the shot entity, and record the time.
    lastFire = System.currentTimeMillis();
    ShotEntity shot2 = new ShotEntity(this,"sprites/shot.png",ship.getX()+50,ship.getY()-30);
    entities.add(shot2);
            // if we waited long enough, create the shot entity, and record the time.
    lastFire = System.currentTimeMillis();
    ShotEntity shot3 = new ShotEntity(this,"sprites/shot.png",ship.getX()-10,ship.getY()-30);
    entities.add(shot3);
            }
}
    public void tryToFireExtra() {
    // check that we have waiting long enough to fire
    if (System.currentTimeMillis() - lastFire < ExtraFiringInterval) {
        return;
    }

    // if we waited long enough, create the shot entity, and record the time.
            lastFire = System.currentTimeMillis();
            ShotEntityExtra shotExtra = new ShotEntityExtra(this,"sprites/shotExtra.png",ship.getX(),ship.getY()-30);
    entities.add(shotExtra);
            // if we waited long enough, create the shot entity, and record the time.
            lastFire = System.currentTimeMillis();
            ShotEntityExtra shotExtra2 = new ShotEntityExtra(this,"sprites/shotExtra.png",ship.getX()+50,ship.getY()-30);
    entities.add(shotExtra2);
            if (level == 9){
                // if we waited long enough, create the shot entity, and record the time.
            lastFire = System.currentTimeMillis();
            ShotEntityExtra shotExtra3 = new ShotEntityExtra(this,"sprites/shotExtra.png",ship.getX()+25,ship.getY()-30);
    entities.add(shotExtra3);

            }
            if (level == 10){
                // if we waited long enough, create the shot entity, and record the time.
            lastFire = System.currentTimeMillis();
            ShotEntityExtra shotExtra3 = new ShotEntityExtra(this,"sprites/shotExtra.png", (int) (ship.getX()+12.5),ship.getY()-30);
    entities.add(shotExtra3);
            // if we waited long enough, create the shot entity, and record the time.
            lastFire = System.currentTimeMillis();
            ShotEntityExtra shotExtra4 = new ShotEntityExtra(this,"sprites/shotExtra.png", (int) (ship.getX()+37.5),ship.getY()-30);
    entities.add(shotExtra4);
            // if we waited long enough, create the shot entity, and record the time.
            lastFire = System.currentTimeMillis();
            ShotEntityExtra shotExtra5 = new ShotEntityExtra(this,"sprites/shotExtra.png", (int) (ship.getX()+25),ship.getY()-30);
    entities.add(shotExtra5);
            }
}
    public void tryToFireBomb() {
    // check that we have waiting long enough to fire
    if (System.currentTimeMillis() - lastFire < bombFiringInterval) {
        return;
    }

    // if we waited long enough, create the shot entity, and record the time.
            lastFire = System.currentTimeMillis();
            Bomb bomb = new Bomb(this,"sprites/bomb.png",ship.getX(),ship.getY()-30);
    entities.add(bomb);
            // if we waited long enough, create the shot entity, and record the time.
            lastFire = System.currentTimeMillis();
            Bomb bomb2 = new Bomb(this,"sprites/bomb.png",ship.getX()+10,ship.getY()-30);
    entities.add(bomb2);
}
public void gameLoop() {
    long lastLoopTime = System.currentTimeMillis();

    // keep looping round til the game ends
    while (gameRunning) {
        // work out how long its been since the last update, this
        // will be used to calculate how far the entities should
        // move this loop
        long delta = System.currentTimeMillis() - lastLoopTime;
        lastLoopTime = System.currentTimeMillis();

        // Get hold of a graphics context for the accelerated 
        // surface and blank it out
        Graphics2D g = (Graphics2D) strategy.getDrawGraphics();
                    //g.drawImage(img, 0, 0,xSize, ySize, null);
                    g.drawRect(0, 0, xSize, ySize);
                    g.fillRect(0, 0, xSize, ySize);
                    g.setColor(Color.BLACK);
        // cycle round asking each entity to move itself
        if (!waitingForKeyPress) {
            for (int i=0;i<entities.size();i++) {
                Entity entity = (Entity) entities.get(i);

                entity.move(delta);
            }
        }

        // cycle round drawing all the entities we have in the game
        for (int i=0;i<entities.size();i++) {
            Entity entity = (Entity) entities.get(i);

            entity.draw(g);
        }

        // brute force collisions, compare every entity against
        // every other entity. If any of them collide notify 
        // both entities that the collision has occured
        for (int p=0;p<entities.size();p++) {
            for (int s=p+1;s<entities.size();s++) {
                Entity me = (Entity) entities.get(p);
                Entity him = (Entity) entities.get(s);

                if (me.collidesWith(him)) {
                    me.collidedWith(him);
                    him.collidedWith(me);
                }
            }
        }

        // remove any entity that has been marked for clear up
        entities.removeAll(removeList);
        removeList.clear();

        // if a game event has indicated that game logic should
        // be resolved, cycle round every entity requesting that
        // their personal logic should be considered.
        if (logicRequiredThisLoop) {
            for (int i=0;i<entities.size();i++) {
                Entity entity = (Entity) entities.get(i);
                entity.doLogic();
            }

            logicRequiredThisLoop = false;
        }

        // if we're waiting for an "any key" press then draw the 
        // current message 
        if (waitingForKeyPress) {
            g.setColor(Color.white);
            g.drawString(message,(800-g.getFontMetrics().stringWidth(message))/2,250);
            g.drawString("Press any key to start game",(800-g.getFontMetrics().stringWidth("Press any key to start game"))/2,300);
        }
                    //score
        g.setColor(Color.WHITE);
        g.drawString("" + alienCount,10,10);
                    g.drawString(" Aliens left", 25, 10);
                    //level
                    g.setColor(Color.WHITE);
        g.drawString("" + level,50,20);
        g.drawString(" Level:", 10, 20);
        // finally, we've completed drawing so clear up the graphics
        // and flip the buffer over
        g.dispose();

导入java.awt.BorderLayout；
导入java.awt.Canvas；
导入java.awt.Color；
导入java.awt.Dimension；
导入java.awt.Graphics2D；
导入java.awt.Image；
导入java.awt.Toolkit；
导入java.awt.event.KeyAdapter；
导入java.awt.event.KeyEvent；
导入java.awt.event.WindowAdapter；
导入java.awt.event.WindowEvent；
导入java.awt.image.BufferStrategy；
导入java.util.ArrayList；
导入javax.swing.JButton；
导入javax.swing.JFrame；
导入javax.swing.JPanel；
公共类游戏扩展画布{
/**要绘制的图像变量*/
图像imgLevel；
图像增强；
图像img；
JFrame容器；
私人缓冲战略；
私有布尔gameRunning=true；
私有ArrayList实体=新ArrayList（）；
private ArrayList removeList=new ArrayList（）；
私人实体船舶；
私人双移动速度=500；
私人长lastFire=0；
私人长飞行间隔；
专用长引燃间隔=100；
私人长轰炸间隔=500；
私人帐户；
私有字符串消息=”；
私有布尔waitingForKeyPress=true；
私有布尔leftPressed=false；
private boolean rightPressed=false；
private boolean upPressed=false；
private boolean downPressed=false；
private boolean firpressed=false；
私有布尔值fireExtraPressed=false；
私有布尔值=false；
私有布尔逻辑RequiredThisloop=false；
静态整数级=8；
私人装甲；
Toolkit tk=Toolkit.getDefaultToolkit（）；
intxsize=（（int）tk.getScreenSize（）.getWidth（））；
int-ySize=（（int）tk.getScreenSize（）.getHeight（））；
/**
*构建我们的游戏并使其运行。
*/
公共游戏（）{
img=Toolkit.getDefaultToolkit（）.createImage（“Bg.gif”）；
容器=新JFrame（“太空入侵者模型”）；
container.setSize（xSize，ySize）；
container.show（）；
JPanel面板=（JPanel）container.getContentPane（）；
面板设置尺寸（xSize、ySize）；
panel.setLayout（空）；
container.setSize（xSize，ySize）；
立根（0,0，xSize，ySize）；
小组。添加（本）；
setIgnoreRepaint（真）；
container.pack（）；
容器。可设置大小（true）；
container.setVisible（true）；
container.addWindowListener（新的WindowAdapter（）{
@凌驾
公共无效窗口关闭（WindowEvent e）{
系统出口（0）；
}
});
addKeyListener（新的KeyInputHandler（））；
requestFocus（）；
创新战略（2）；
strategy=getBufferStrategy（）；
初始化实体（）；
}
/**
*开始一个新的游戏，这应该清除所有旧数据和
*创建一个新集合。
*/
私有void startGame（）{
实体。清除（）；
初始化实体（）；
leftPressed=false；
右压=假；
upPressed=false；
按下=假；
壁炉=假；
fireExtraPressed=false；
bombFired=false；
飞行间隔=100；
}
/**
*初始化实体（船舶和外国人）的起始状态。每个
*实体将被添加到游戏中实体的总列表中。
*/
私有实体（）{
ship=新的ShipEntity（这个“sprites/ship.png”，370，ySize-130）；
实体。添加（船舶）；
alienCount=0；
如果（级别==1）{
装甲=10；
对于（int row=0；row我建议您在继续之前阅读一些

下面是一个简单的通用示例，介绍如何将
JButton
添加到
JFrame
：

JFrame frame = new JFrame("FrameDemo");
JButton button = new JButton("upgrade"); //The JButton name.
frame.add(button); //Add the button to the JFrame.
frame.setSize(200, 200);
frame.setVisible(true);

如果你了解这5行代码是如何工作的，你可以将它应用到你正在做的任何事情上。
plsI知道如何使用它们，但它仍然不适用于此。还有其他建议吗？@user2149407 no1将阅读500行代码来回答你的问题，你需要更具体地说明它是如何“不工作”的请切换最后两个代码lines@mKorbel对不起，修好了