Question

这不是我正在处理的整个程序，我可能需要编辑更多信息才能解决这个问题。该程序创建一个窗口并用背景颜色填充它。然后我希望我的处理程序类创建两个玩家（方框）并将它们放在两个单独的坐标上。我收到错误＆＃34;无法实例化类型播放器＆＃34; ，但是Player是一个抽象类，不需要做什么？

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;

public class Game extends Canvas implements Runnable {

public static final int WIDTH = 640, HEIGHT = WIDTH / 12 *9;
private Thread thread;
private boolean running = false;
private Handler handler;

public Game (){
    new Window (WIDTH, HEIGHT, "a game", this);
    //above creates the window of the game

    handler = new Handler();
    handler.addObject(new Player(100, 100, ID.Player));
    handler.addObject(new Player (200, 200, ID.Player));
    //these two lines are marked as the truble, 
   // Cannot instantiate the type Player
}

///////

import java.awt.Graphics;
import java.util.LinkedList;

public class Handler {
LinkedList<GameObject> object = new LinkedList<GameObject>();
//creates a list called Linkedlist this contains all objects  

public void tick(){
//for making the game tick
    for (int i = 0; i < object.size(); i++){
        GameObject tempObject = object.get(i);
        tempObject.tick(); 
    }
}

public void render (Graphics g){
    for (int i = 0 ; i <object.size();i++){
        GameObject tempObject = object.get(i);
        tempObject.render(g);   
    }
}

public void addObject (GameObject object){
    this.object.add(object);
//this is supposed to be called from Game class, and is supposed to add 
//one object to the list.
    }
}

////

import java.awt.Graphics;

public abstract class GameObject {  
protected int x, y;
protected ID id;
protected int velX, velY;

public GameObject(int x, int y, ID id){
    this.x = x;
    this.y = y;
    this.id = id;
}

public abstract void tick();
//abstract means it has to be used in all classes

public abstract void render(Graphics g);

}

///////

import java.awt.Color;
import java.awt.Graphics;

public abstract class Player extends GameObject {

    public Player(int x, int y, ID id) {
        super(x, y, id);//cordinates and tag    
    }

    public void tick(){
    }

    public void render(Graphics g){
        //this are the two bockes I want to create in my window
        g.setColor(Color.white);
        g.fillRect(x, y, 32, 32);
    }
}

Answer 1

Player是一个抽象类，所以你不能这样做：

new Player(100, 100, ID.Player)

为什么新对象没有显示在窗口中？

1 个答案: