Python Crash Course - Alien Invasion - Error

问题

I am doing the Alien Invasion project in the Python Crash Course book. When I test the code to see if the ship comes on screen the screen starts then shuts down.

I have been looking through the code for hours now without finding out why.

The game:

import sys
import pygame
from settings import Settings
from ship import Ship


def run_game():
    # Initialize pygame, settings, and screen object
    pygame.init()
    ai_settings = Settings()
    screen = pygame.display.set_mode(
        (ai_settings.screen_width, ai_settings.screen_height))
    pygame.display.set_caption("Alien Invasion")

    # Make a ship
    ship = Ship(screen)

    # Set background color
    bg_color = (230, 230, 230)

    # Start the main loop for the game
    while True:

        # Watch for keyboard and mouse events
        for event in pygame.event.get():
            if event == pygame.quit():
                sys.exit()

        # Redraw the screen during each pass through the loop
        screen.fill(ai_settings.bg_color)
        ship.blitme()

        # Make most recently drawn screen visible
        pygame.display.flip()


run_game()

Settings:

class Settings():

    def __init__(self):
        """Initialize the game's settings."""
        # Screen settings
        self.screen_width = 1200
        self.screen_height = 800
        self.bg_color = (230, 230, 230)

Ship:

import pygame


class Ship():
    def __init__(self, screen):
        self.screen = screen

        # Load the ship image and get its rect.
        self.image = pygame.image.load('images/ship.bmp')
        self.rect = self.image.get_rect()
        self.screen_rect = screen.get_rect()

        # Start each new ship at the bottom center of the screen.
        self.rect.centerx = self.screen_rect.centerx
        self.rect.bottom = self.screen_rect.bottom

    def blitme(self):
        self.screen.blit(self.image, self.rect)

This is the error that comes up

"C:\Users\My Name\Desktop\Mapper\Python'\Scripts\python.exe" "C:/Users/My Name/Desktop/Mapper/Python/Projects/alien invasion/alien_invasion.py"
pygame 1.9.6
Hello from the pygame community. https://www.pygame.org/contribute.html
Traceback (most recent call last):
  File "C:/Users/My Name/Desktop/Mapper/Python/Projects/alien invasion/alien_invasion.py", line 37, in <module>
    run_game()
  File "C:/Users/My Name/Desktop/Mapper/Python/Projects/alien invasion/alien_invasion.py", line 30, in run_game
    screen.fill(ai_settings.bg_color)
pygame.error: display Surface quit

Process finished with exit code 1

回答1:

The line

if event == pygame.quit():

doesn't do what you expect it to do. pygame.quit() is a function and it uninitialize all pygame modules. The function returns None and so the condition fails. The code runs through and crashes at the next instruction which tries to access a pygame module.

Change it to:

if event.type == pygame.QUIT:

The .type property of a pygame.event.Event object contains the event type identifier. pygame.QUIT is an enumerator constant which identifies the quit event. See the documentation of pygame.event.

来源：https://stackoverflow.com/questions/56150893/python-crash-course-alien-invasion-error

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python

pygame