Xna-共享相同纹理的对象

Question

In my game, I have an Ai class which is basically just a linked list of every ai in my game. this same class holds the default textures for every ai, and all of my ai's seperate classes inherit from this class, that way they all can inherit the default textures that were already loaded by the ai class. However, I seem to be having problems with this. My game never loads up the gui when ran, and through debugging, it seems like the game has problems with the textures I am passing. Are you not able to load a single texture and pass that same texture for another object to use?

AI class:

class AIs
{
    private GraphicsDevice graphics;
    private ContentManager content;
    private SpriteBatch spriteBatch;
    private LinkedList<object> ais;
    private LinkNode<object> current;

    //Default Textures
    private Texture2D robotTexture

    // Default Color Datas
    private Color[] robotColorData;

    public AIs()
    {
    }

    public void Load(ContentManager content, GraphicsDevice graphics, SpriteBatch spriteBatch)
    {
        this.spriteBatch = spriteBatch;
        this.graphics = graphics;
        this.content = content;

        // Loading Default Textures
        robotTexture = content.Load<Texture2D>("robot");

        // Loading Default Color Data
        robotColorData = new Color[robotTexture.Width * robotTexture.Height];
        robotTexture.GetData(robotColorData);
    }

    public void Update()
    {
        current = ais.getHead();

        while (current.getNext() != null)
        {
            if (current.getData() is Robot)
            {
                ((Robot)current.getData()).Update();
            }
        }
    }

    public void Draw()
    {
        current = ais.getHead();

        while (current.getNext() != null)
        {
            if (current.getData() is Robot)
            {
                ((Robot)current.getData()).Draw();
            }
        } 
    }

    public addRobot(float spawnX, float spawnY)
    {
        Robot temp = new Robot(spawnX, spawnY);
        temp.Load(content, graphics, spriteBatch);
        ais.add(temp);
    }

    public Texture2D getRobotTexture()
    {
        return robotTexture;
    }

    public Color[] getRobotColorData()
    {
        return robotColorData;
    }
}

Robot Class:

class Robot : AIs
{
    private GraphicsDevice graphics;
    private ContentManager content;
    private SpriteBatch spriteBatch;
    private Texture2D robotTexture;
    private Color[] robotColorData;
    private Rectangle robotRectangle;
    private Vector2 robotPosition = Vector2.Zero;

    public Robot(float spawnX, float spawnY)
    {
        robotPosition = new Vector2(spawnX, spawnY);
    }

    new public void Load(ContentManager content, GraphicsDevice graphics, SpriteBatch spriteBatch)
    {
        this.spriteBatch = spriteBatch;
        this.graphics = graphics;
        this.content = content;
        robotTexture = getRobotTexture();
        robotColorData = getRobotColorData();
    }

    new public void Update()
    {
        robotRectangle = new Rectangle((int)robotPosition.X, (int)robotPosition.Y, robotTexture.Width, robotTexture.Height);

    }

    new public void Draw()
    {
        spriteBatch.Draw(robotTexture, robotPosition, Color.White);
    }
}

Answer 1

Turns out, all you have to do is add the keyword "static" next to the texture and color data. If you don't put static, then when the class is created, it will inherit the methods and variables, but the variables will be new, null, because it is a new instance of the class. So putting static next to it makes the value stay the same for all instances.

In the AI class:

//Default Textures
private static Texture2D robotTexture

// Default Color Datas
private static Color[] robotColorData;

Answer 2

It seems the problem here is in your use of inheritance.

What happens is that you run your robots Load-method, which fetches robotTexture from itself through AIs getRobotTexture-method. That method just returns robotTexture, so you might as well write robotTexture = robotTexture.

But since this instance has not ran AIs.Load, robotTexture is null.

To be brutally honest; Read up on inheritance!

To be more helpful;

It seems that what you are really after is having a robotmanager that simplifies the spawning of robots. For this, inheritance is not the answer. Try something like this instead:

public class RobotManager
{
    private SpriteBatch spriteBatch;
    private Texture2D robotTexture;

    private List<Robot> robots;

    public RobotManager(SpriteBatch spriteBatch, Texture2D texture)
    {
        this.spriteBatch = spriteBatch;
        this.robotTexture = texture;

        robots = new List<Robot>();
    }

    public void Update()
    {
        foreach (var robot in robots)
            robot.Update();
    }

    public void Draw()
    {
        foreach (var robot in robots)
            robot.Draw();
    }

    public void AddRobot(Vector2 position, Texture2D customTexture = null)
    {
        //Creates a new robot with position set and custom texture if specified
        var newRobot = new Robot(spriteBatch, position, (customTexture == null) ? robotTexture : customTexture);
        robots.Add(newRobot);
    }

}