python - 当我的蛇的坐标与我的随机项目相同时，控制台应该打印 "You got the item!"但事实并非如此。为什么？

Question

这是创建我的 Snake 基础的代码。

class Snake(object):
    x_coordinate = 0
    y_coordinate = 0

    def __init__(self, x_coordinate, y_coordinate):
        grid[x_coordinate][y_coordinate] = 1
        Snake.x_coordinate = x_coordinate
        Snake.y_coordinate = y_coordinate
        print(Snake.x_coordinate)
        print(Snake.y_coordinate)

    @staticmethod
    def move_snake(direction):
        if direction == "UP":
            old_x = Snake.x_coordinate
            old_y = Snake.y_coordinate
            grid[old_x][old_y] = 0
            grid[old_x - 1][old_y] = 1
            Snake.x_coordinate = old_x - 1
            print("UP")
        if direction == "DOWN":
            old_x = Snake.x_coordinate
            old_y = Snake.y_coordinate
            grid[old_x][old_y] = 0
            grid[old_x + 1][old_y] = 1
            Snake.x_coordinate = old_x + 1
            print("DOWN")
        if direction == "LEFT":
            old_x = Snake.x_coordinate
            old_y = Snake.y_coordinate
            grid[old_x][old_y] = 0
            grid[old_x][old_y - 1] = 1
            Snake.y_coordinate = old_y - 1
            print("LEFT")
        if direction == "RIGHT":
            old_x = Snake.x_coordinate
            old_y = Snake.y_coordinate
            grid[old_x][old_y] = 0
            grid[old_x][old_y + 1] = 1
            Snake.y_coordinate = old_y + 1
            print("RIGHT")
        print("Your X and Y coordinates are {0} and {1}".format(Snake.x_coordinate, Snake.y_coordinate))

这是创建我需要获取的随机对象的代码。

class RandomObject(object):
    x_coordinate = 0
    y_coordinate = 0

    def __init__(self):
        x_coordinate = random.randint(1, 15)
        y_coordinate = random.randint(1, 15)
        grid[x_coordinate][y_coordinate] = 2
        print("The items x and y coordinates are {0} and {1}".format(x_coordinate, y_coordinate))

我将它们声明为 Snake 和 random_item 变量。我也将其放入我的 pygame 事件函数中。

    elif snake.x_coordinate == randomItem.x_coordinate and snake.y_coordinate == randomItem.y_coordinate:
        print("You got the item.")

那么这里的问题是什么？它应该可以工作，因为当我将蛇移动到随机项目坐标时，它会打印出它们位于同一坐标但没有任何反应，该事件不会被触发。

Answer 1

您从未设置实例属性:

class RandomObject(object):
    x_coordinate = 0
    y_coordinate = 0

    def __init__(self):
        x_coordinate = random.randint(1, 15)
        y_coordinate = random.randint(1, 15)
        grid[x_coordinate][y_coordinate] = 2
        print("The items x and y coordinates are {0} and {1}".format(x_coordinate, y_coordinate))

__init__ 方法设置本地值，当函数退出时这些值会再次丢失。 RandomObject 实例没有设置属性，因此当您访问 randomItem 上的属性时，只能找到类属性(均设置为 0) >.

将它们设置在实例上:

class RandomObject(object):
    x_coordinate = 0
    y_coordinate = 0

    def __init__(self):
        self.x_coordinate = random.randint(1, 15)
        self.y_coordinate = random.randint(1, 15)
        grid[self.x_coordinate][self.y_coordinate] = 2
        print("The items x and y coordinates are {0} and {1}".format(self.x_coordinate, self.y_coordinate))

注意self.引用。