为什么我的代码无法定义car_racing，以及如何从菜单无缝过渡到游戏？

Question

import random
from time import sleep

import pygame


class CarRacing:
    def __init__(self):

        pygame.init()
        self.display_width = 800
        self.display_height = 600
        self.black = (0, 0, 0)
        self.white = (255, 255, 255)
        self.clock = pygame.time.Clock()
        self.gameDisplay = None
        self.initialize()

    def initialize(self):

        self.crashed = False

        self.carImg = pygame.image.load('.\\img\\car.png')
        self.car_x_coordinate = (self.display_width * 0.45)
        self.car_y_coordinate = (self.display_height * 0.8)
        self.car_width = 49

        # enemy_car
        self.enemy_car = pygame.image.load('.\\img\\enemy_car_1.png')
        self.enemy_car_startx = random.randrange(310, 450)
        self.enemy_car_starty = -600
        self.enemy_car_speed = 5
        self.enemy_car_width = 49
        self.enemy_car_height = 100

        # Background
        self.bgImg = pygame.image.load(".\\img\\background-1_0.png")
        self.bg_x1 = (self.display_width / 2) - (360 / 2)
        self.bg_x2 = (self.display_width / 2) - (360 / 2)
        self.bg_y1 = 0
        self.bg_y2 = -600
        self.bg_speed = 3
        self.count = 0

    def car(self, car_x_coordinate, car_y_coordinate):
        self.gameDisplay.blit(self.carImg, (car_x_coordinate, car_y_coordinate))

    def racing_window(self):
        self.gameDisplay = pygame.display.set_mode((self.display_width, self.display_height))
        pygame.display.set_caption('Inline Overdrive')
        self.run_car()

    def run_car(self):

        while not self.crashed:

            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    self.crashed = True
                # print(event)

                if (event.type == pygame.KEYDOWN):
                    if (event.key == pygame.K_LEFT):
                        self.car_x_coordinate -= 50
                        print ("CAR X COORDINATES: %s" % self.car_x_coordinate)
                    if (event.key == pygame.K_RIGHT):
                        self.car_x_coordinate += 50
                        print ("CAR X COORDINATES: %s" % self.car_x_coordinate)
                    print ("x: {x}, y: {y}".format(x=self.car_x_coordinate, y=self.car_y_coordinate))

            self.gameDisplay.fill(self.black)
            self.back_ground_road()

            self.run_enemy_car(self.enemy_car_startx, self.enemy_car_starty)
            self.enemy_car_starty += self.enemy_car_speed

            if self.enemy_car_starty > self.display_height:
                self.enemy_car_starty = 0 - self.enemy_car_height
                self.enemy_car_startx = random.randrange(310, 450)

            self.car(self.car_x_coordinate, self.car_y_coordinate)
            self.highscore(self.count)
            self.count += 1
            if (self.count % 100 == 0):
                self.enemy_car_speed += 1
                self.bg_speed += 1
            if self.car_y_coordinate < self.enemy_car_starty + self.enemy_car_height:
                if self.car_x_coordinate > self.enemy_car_startx and self.car_x_coordinate < self.enemy_car_startx + self.enemy_car_width or self.car_x_coordinate + self.car_width > self.enemy_car_startx and self.car_x_coordinate + self.car_width < self.enemy_car_startx + self.enemy_car_width:
                    self.crashed = True
                    self.display_message("You have crashed!")

            if self.car_x_coordinate < 310 or self.car_x_coordinate > 460:
                self.crashed = True
                self.display_message("You have crashed!")

            pygame.display.update()
            self.clock.tick(60)

    def display_message(self, msg):
        font = pygame.font.SysFont("comicsansms", 72, True)
        text = font.render(msg, True, (255, 255, 255))
        self.gameDisplay.blit(text, (400 - text.get_width() // 2, 240 - text.get_height() // 2))
        self.display_credit()
        pygame.display.update()
        self.clock.tick(60)
        sleep(1)
        car_racing.initialize()
        car_racing.racing_window()

    def back_ground_road(self):
        self.gameDisplay.blit(self.bgImg, (self.bg_x1, self.bg_y1))
        self.gameDisplay.blit(self.bgImg, (self.bg_x2, self.bg_y2))

        self.bg_y1 += self.bg_speed
        self.bg_y2 += self.bg_speed

        if self.bg_y1 >= self.display_height:
            self.bg_y1 = -600

        if self.bg_y2 >= self.display_height:
            self.bg_y2 = -600

    def run_enemy_car(self, thingx, thingy):
        self.gameDisplay.blit(self.enemy_car, (thingx, thingy))

    def highscore(self, count):
        font = pygame.font.SysFont("arial", 20)
        text = font.render("Score : " + str(count), True, self.white)
        self.gameDisplay.blit(text, (0, 0))

    def display_credit(self):
        font = pygame.font.SysFont("lucidaconsole", 14)
        text = font.render("Thank You For Playing!", True, self.white)
        self.gameDisplay.blit(text, (600, 520))

import pygame
from pygame.locals import *
import os

# Game Initialization
pygame.init()

# Center the Game Application
os.environ['SDL_VIDEO_CENTERED'] = '1'

# Game Resolution
screen_width=800
screen_height=600
screen=pygame.display.set_mode((screen_width, screen_height))

# Text Renderer
def text_format(message, textFont, textSize, textColor):
    newFont=pygame.font.Font(textFont, textSize)
    newText=newFont.render(message, 0, textColor)

    return newText


# Colors
white=(255, 255, 255)
black=(0, 0, 255)
gray=(50, 50, 50)
red=(255, 0, 0)
green=(0, 255, 0)
blue=(0, 0, 0)
yellow=(255, 255, 0)

# Game Fonts
font = "RacingNumbers.ttf"


# Game Framerate
clock = pygame.time.Clock()
FPS=30

# Main Menu
def main_menu():

    menu=True
    selected="start"

    while menu:
        for event in pygame.event.get():
            if event.type==pygame.QUIT:
                pygame.quit()
                quit()
            if event.type==pygame.KEYDOWN:
                if event.key==pygame.K_UP:
                    selected="start"
                elif event.key==pygame.K_DOWN:
                    selected="quit"
                elif event.key==pygame.K_DOWN:
                    selected="options"
                if event.key==pygame.K_RETURN:
                    if selected=="start":
                        car_racing = CarRacing()
                        car_racing.racing_window()
                    if selected=="quit":
                        pygame.quit()
                        quit()
                    if selected=="options":
                            print(options)
                    
                        

        # Main Menu UI
        screen.fill(blue)
        title=text_format("Inline Overdrive", font, 90, white)
        if selected=="start":
            text_start=text_format("START", font, 75, red)
        else:
            text_start = text_format("START", font, 75, white)
        if selected=="quit":
            text_quit=text_format("QUIT", font, 75, red)
        else:
            text_quit = text_format("QUIT", font, 75, white)
        if selected=="options":
            text_options=text_format("OPTIONS", font, 75, red)
        else:
            text_options = text_format("OPTIONS", font, 75, white)

            
        title_rect=title.get_rect()
        start_rect=text_start.get_rect()
        quit_rect=text_quit.get_rect()
        options_rect=text_options.get_rect()

        # Main Menu Text
        screen.blit(title, (screen_width/2 - (title_rect[2]/2), 80))
        screen.blit(text_start, (screen_width/2 - (start_rect[2]/2), 300))
        screen.blit(text_quit, (screen_width/2 - (quit_rect[2]/2), 360))
        screen.blit(text_options, (screen_width/2 - (quit_rect[2]/2), 420))
        pygame.display.update()
        clock.tick(FPS)
        pygame.display.set_caption("Inline Overdrive")

#Initialize the Game
main_menu()
pygame.quit()
quit()

当汽车撞到树区时，它显示的是：

回溯(最近一次调用)：文件"\hs-srv-hsdc-fs2\2015_hd\14782\Documents\Year 12和13\计算机科学\单元3\最终产品\在线过驱动测试4.py"，第238行，在main_menu()文件"\hs-srv-hsdc-fs2\2015_hd\14782\Documents\Year 12和13\计算机科学\单元3\最终产品\在线过驱动测试4.py"，第197行，在"\hs-srv-hsdc-fs2\2015_hd\14782\Documents\Year 12和13\Computer self.run_car()文件"\hs-srv-hsdc-fs2\2015_hd\14782\Documents\Year 12和13\Computer Science\Unit 3\Final Product\Inline Overdrive Test4.py“中，第51行，在racing_window self.run_car()文件”\hs-srv-hsdc-fs2\2015_hd\14782\Documents\Year 12和13\Computer self.run_car\Unit 3\Final Product\Inline Overdrive Test4.py“中，在run_car self.display_message中，第94行(”You have crashed!")File "\hs-srv-hsdc-fs2\2015_hd\14782\Documents\Year 12 and 13\Computer Science\Unit3\Final Product\Inline Overdrive Test4.py“，display_message car_racing.initialize() NameError: name 'car_racing‘中的第107行

为什么没有定义car_racing，如何让我的游戏从菜单无缝过渡到游戏？

Answer 1

好的，这就是问题所在，你调用car_racing.initialize()和car_racing.racing_window()的方法无法访问car_racing实例。我建议您在编写这种冗长且“复杂”的代码时，使用一些IDE来查看这些问题。顺便说一句，这里还有一些其他的问题，比如这里，print(options)一旦你的代码到达这里，你会在这里得到另一个错误。我更新了你的代码，花了一些时间，但它不会给你同样的错误，run_car方法和display_message方法是这里的提示符，这里使用这个方法，而我所做的就是将initialize和racing_window方法移到上面，你的代码可以访问它们。

def run_car(self):

    while not self.crashed:

        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                self.crashed = True
            # print(event)

            if event.type == pygame.KEYDOWN:
                if event.key == pygame.K_LEFT:
                    self.car_x_coordinate -= 50
                    print("CAR X COORDINATES: %s" % self.car_x_coordinate)
                if event.key == pygame.K_RIGHT:
                    self.car_x_coordinate += 50
                    print("CAR X COORDINATES: %s" % self.car_x_coordinate)
                print("x: {x}, y: {y}".format(x=self.car_x_coordinate, y=self.car_y_coordinate))

        self.gameDisplay.fill(self.black)
        self.back_ground_road()

        self.run_enemy_car(self.enemy_car_startx, self.enemy_car_starty)
        self.enemy_car_starty += self.enemy_car_speed

        if self.enemy_car_starty > self.display_height:
            self.enemy_car_starty = 0 - self.enemy_car_height
            self.enemy_car_startx = random.randrange(310, 450)

        self.car(self.car_x_coordinate, self.car_y_coordinate)
        self.highscore(self.count)
        self.count += 1
        if (self.count % 100 == 0):
            self.enemy_car_speed += 1
            self.bg_speed += 1
        if self.car_y_coordinate < self.enemy_car_starty + self.enemy_car_height:
            if self.car_x_coordinate > self.enemy_car_startx and self.car_x_coordinate < self.enemy_car_startx + self.enemy_car_width or self.car_x_coordinate + self.car_width > self.enemy_car_startx and self.car_x_coordinate + self.car_width < self.enemy_car_startx + self.enemy_car_width:
                self.crashed = True
                self.display_message("You have crashed!")
                self.initialize()
                self.racing_window()

        if self.car_x_coordinate < 310 or self.car_x_coordinate > 460:
            self.crashed = True
            self.display_message("You have crashed!")
            self.initialize()
            self.racing_window()

        pygame.display.update()
        self.clock.tick(60)

def display_message(self, msg):
    font = pygame.font.SysFont("comicsansms", 72, True)
    text = font.render(msg, True, (255, 255, 255))
    self.gameDisplay.blit(text, (400 - text.get_width() // 2, 240 - text.get_height() // 2))
    self.display_credit()
    pygame.display.update()
    self.clock.tick(60)
    sleep(1)