pygame对象返回错误的按钮对象

Question

我遇到了这样的问题：当我在我的pygame应用程序中添加3个时，所有按钮的背景都与上次添加的按钮相同。

我有窗口课程：

class MainMenuWindow(Window):

    # singeltone:
    _instance = None
    def __new__(cls, *args, **kwargs):
        if not cls._instance:
            cls._instance = super(MainMenuWindow, cls).__new__(cls, *args, **kwargs)
        return cls._instance

    def __init__(self):
        self.background = pygame.transform.scale(pygame.image.load(GLOBAL_APPLICATION_ROOT_PATH.__str__() + "/src/img/backgrounds/main_window.jpg"), \
            (GLOBAL_SCREEN_WIDTH, GLOBAL_SCREEN_HEIGHT))

        self.window = pygame.display.get_surface()

        pygame.mouse.set_visible(1)
        pygame.key.set_repeat(0)

        btn = Button((130,22),(250,200),"start_playing.png","start_playing","")
        btn2 = Button((130,22),(250,250),"options.png","options","")
        btn3 = Button((130,22),(250,450),"exit.png","exit","")

        self.buttons_list.append(btn)
        self.buttons_list.append(btn2)
        self.buttons_list.append(btn3)

    def draw(self):
        """
         Render buttons on screen
        """
        self.window.blit(self.background, (0, 0))
        for btn in self.buttons_list:
            btn.render()

班级按钮：

class Button(Element):
    """
        Sprites sheet MUST contain 4 representative images in following order: 'normal','hover','active','disabled'

    """

    __src_path = os.path.join(GLOBAL_APPLICATION_ROOT_PATH,"src","img","interface")

    # width & height of button
    button_size = (100,50)
    # x, y position coordinates
    button_position = (0,0)
    # list of button background states @Surfaces
    button_background = {'normal': None, 'hover': None, 'active': None, 'disabled': None}
    # atlas with button states backgrounds
    master_image_atlas = None
    # button ID
    button_id = ""
    # text on button
    button_caption = "Button"
    # rect object
    button_rect = pygame.Rect(button_position, button_size)

    button_status = "normal"    # can be 'normal', 'hover', 'active', 'disabled'
    hover = False
    pressed = False


    def __init__(self, size=(20, 10), position=(0, 0), image_atlas="", btn_id="btn_1", btn_caption="Button1"):
        """

            :param size:            (x,y) size of button
            :param position:        (x,y) position coordinates
            :param image_atlas:     name of image file with button sprites
            :param btn_id:          string ID of button
            :param btn_caption:     Button caption

        """

        super().__init__()
        self.button_size = size
        self.button_position = position
        self.master_image_atlas = image_atlas
        self.button_id = btn_id
        self.button_caption = btn_caption
        self.button_rect = pygame.Rect(self.button_position[0], self.button_position[1], self.button_size[0],self.button_size[1])
        self.prepare()


    def prepare(self):
        """
            Create complete Button object
        """
        image_atlas = None

        if self.master_image_atlas != None:
            image_atlas = slice_image(os.path.join(self.__src_path,"buttons",self.master_image_atlas), self.button_size[0],self.button_size[1])
            self.button_background['normal'] = image_atlas[0][0]
            self.button_background['hover'] = image_atlas[0][1]
            self.button_background['active'] = image_atlas[0][2]
            self.button_background['disabled'] = image_atlas[0][3]
        else:
            image_atlas = None

        return self

    def render(self):
        screen = pygame.display.get_surface()
        screen.blit(self.button_background[self.button_status],self.button_position)

    def update_state(self,event_handler_object):
        state =  event_handler_object.check_element_state(self)

        if state[1] is None:
            self.set_visual_status("normal")
            self.pressed = False
            return
        elif state[1]['status'] == "hover":
            self.set_visual_status("hover")
            self.pressed = False
            return
        elif state[1]['status'] == "click":
            self.set_visual_status("active")
            self.pressed = True
            return

类元素：

class Element:
    """
    Implements basic functionality for all interface elements

    """

    __src_path = os.path.join(GLOBAL_APPLICATION_ROOT_PATH,"src","img","interface")

    # width & height of button
    button_size = (100,50)
    # x, y position coordinates
    button_position = (0,0)
    # list of button background states @Surfaces
    button_background = {'normal': None, 'hover': None, 'active': None, 'disabled': None}
    # atlas with button states backgrounds
    master_image_atlas = None
    # button ID
    button_id = ""
    # text on button
    button_caption = "Button"
    # rect object
    button_rect = pygame.Rect(button_position, button_size)

    button_status = "normal"    # can be 'normal', 'hover', 'active', 'disabled'
    hover = False
    pressed = False

    def __init__(self,size=(20,10),position=(0,0),image_atlas="",btn_id="btn_1",btn_caption="Button1"):
        pass

    def prepare(self):
        pass

    def update_state(self,event_handler_object):
        pass

    def get_object_id(self):
        return self.button_id

    def get_object_rectangle(self):
        return self.button_rect

    def set_visual_status(self,status):
        self.button_status = status

    def is_pressed(self):
        if self.pressed==True:
            #print(["pressed",self.button_id])
            return self.button_id

    def render(self):
        pass

当我运行我的应用程序时，我有3个具有相同图像的按钮：

当我点击任何按钮时 - 应用程序返回正确的点击按钮ID。 按钮精灵有什么问题？