ArgumentNullException was unhandled What is wrong?

[S.O.S]

I have written a class to load an XML file but I always get this error message:ArgumentNullException was unhandledThis method does not accept null for this parameter.Parameter name: textureI get the error message in the batch.Draw():\[code\]public void Draw(SpriteBatch batch){ batch.Draw( texture, position, null, Color.White, rotation, Vector2.Zero, scale, SpriteEffects.None, 0f); }\[/code\]What is wrong in the Sprite class?I uploaded my project here: http://depositfiles.com/files/kj4an4ef7