我有一个带有main.py的pygame程序导入一个player.py模块，如下所示：
import pygame
import random
from walls import Wall
class Player(pygame.sprite.Sprite):
#-------------------Define Variables here
speed=0
#------------------Initialise Constructor
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image=pygame.image.load("player.png")
self.rect = self.image.get_rect()
#--------------Fetch the rectangle object that has the dimensions of the image
self.rect =self.image.get_rect()
#---------------Define movement
def moveRight(self,pixels):
self.rect.x+=pixels
def moveLeft(self,pixels):
self.rect.x-=pixels
def moveUp(self,pixels):
self.rect.y-=pixels
def moveDown(self,pixels):
self.rect.y+=pixels
# Make our top-left corner the passed-in location.
def settopleft():
self.rect = self.image.get_rect()
self.rect.y = y
self.rect.x = x
# Set speed vector
self.change_x = 0
self.change_y = 0
self.walls = None
def changespeed(self, x, y):
""" Change the speed of the player. """
self.change_x += x
self.change_y += y
def update(self):
# Did this update cause us to hit a wall?
block_hit_list = pygame.sprite.spritecollide(self, self.walls, False)
for block in block_hit_list:
# If we are moving right, set our right side to the left side of
# the item we hit
if self.change_x > 0:
self.rect.right = block.rect.left
else:
# Otherwise if we are moving left, do the opposite.
self.rect.left = block.rect.right
# Move up/down
self.rect.y += self.change_y
# Check and see if we hit anything
block_hit_list = pygame.sprite.spritecollide(self, self.walls, False)
for block in block_hit_list:
# Reset our position based on the top/bottom of the object.
if self.change_y > 0:
self.rect.bottom = block.rect.top
else:
self.rect.top = block.rect.bottom
main.py程序如下：
#Create walls that the player can run into
import pygame
import random
from player import Player
from collectable import Collectable
from walls import Wall
pygame.init()
BLACK=(0,0,0)
WHITE=(255,255,255)
RED=(255,0,0)
GREEN =(0,255,0)
BLUE=(0,0,255)
GOLD=(255,215,0)
WIDTH=500
HEIGHT=500
size= (WIDTH,HEIGHT)
screen=pygame.display.set_mode(size)
pygame.display.set_caption("The Life Game")
done = False
clock=pygame.time.Clock()
wall_list=pygame.sprite.Group()
all_sprites = pygame.sprite.Group()
enemy_list = pygame.sprite.Group()
player=Player()
player.walls=wall_list
all_sprites.add(player)
for i in range(random.randrange(100,200)):
whiteStar = Collectable(WHITE, 3, 3, "White Star", "Rect")
whiteStar.rect.x = random.randrange(size[0])
whiteStar.rect.y = random.randrange(size[1])
all_sprites.add(whiteStar)
for i in range(50):
enemy = Collectable(RED,6, 6,"Enemy","Ellipse")
enemy.rect.x = random.randrange(300)
enemy.rect.y = random.randrange(300)
enemy_list.add(enemy)
all_sprites.add(enemy)
coin1 = Collectable(GOLD,50,50,"Coin","Ellipse")
coin1.rect.x=440
coin1.rect.y=0
all_sprites.add(coin1)
coin2 = Collectable(GOLD,50,50,"Coin","Ellipse")
coin2.rect.x=0
coin2.rect.y=440
all_sprites.add(coin2)
enemy = Collectable(RED,100,100,"Enemy","Ellipse")
enemy.rect.x=70
enemy.rect.y=230
all_sprites.add(enemy)
#Make the walls (x_pos,y_pos, width, height,colour)
wall=Wall(0,0,10,600,GREEN)
wall_list.add(wall)
all_sprites.add(wall_list)
wall = Wall(50, 300, 400, 10,RED)
wall_list.add(wall)
all_sprites.add(wall_list)
wall = Wall(10, 200, 100, 10,BLUE)
wall_list.add(wall)
all_sprites.add(wall_list)
score=0
health=100
#- - - - - - - - - - - - - -Main Program Loop - - - - - - - - - - - - - - - -
def main():
done=False
score=0
health=100
while not done:
#- - - - - - Main event loop (this is where code for handling keyboard and mouse clicks will go)
#Loop until the user clicks the 'x' button (to close program)
for event in pygame.event.get(): #User does something
if event.type == pygame.QUIT: #If the user clicked close
done = True #set the done flag to 'true' to exit the loop
keys = pygame.key.get_pressed() #checking pressed keys
if keys[pygame.K_LEFT]:
player.moveLeft(5)
if keys[pygame.K_RIGHT]:
player.moveRight(5)
if keys[pygame.K_UP]:
player.moveUp(5)
if keys[pygame.K_DOWN]:
player.moveDown(5)
#>>----------DRAW SECTION -----------------------------------
#Clear the screen to BLACK. Any drawing commands should be put BELOW this or they will be reased with this command
screen.fill(BLACK)
#Select the font to be used (size, bold, italics, etc)
font_score = pygame.font.SysFont('Calibri',20,True,False)
font_health = pygame.font.SysFont('Calibri',20,True,False)
#Printing a variable (score or health) to the screen involves converting the score (if integer) to a string first.score_label = font_score.render("Score: " + str(score),True,BLACK)
health_label = font_health.render("Health: "+str(health),True,WHITE)
score_label = font_score.render("Score: " + str(score),True, WHITE)
#Now we can use this line of code to put the image of the text on the screen at a given position
screen.blit(score_label,[100,480])
screen.blit(health_label,[190,480])
#>>---------UPDATE SECTION / Put the logic of your game here (i.e. how objects move, when to fire them, etc)
all_sprites.update()
if coin1.collision_with(player):
score=score+1
coin1.kill()
coin1.rect.x=-20
coin1.rect.y=-330
if coin2.collision_with(player):
score=score+1
coin2.kill()
coin2.rect.x=-20
coin2.rect.y=-330
if enemy.collision_with(player):
health=health-25
enemy.kill()
enemy.rect.x=-20
enemy.rect.y=-330
enemy.update()
#-------------PRINTING VARIABLES LIKE SCORE TO SCREEN
#Any drawing/graphics code should go here
all_sprites.draw(screen)
#Update the screen to show whatever you have drawn
pygame.display.flip()
#Set the frames per second (e.g. 30, 60 etc)
clock.tick(120)
main()
运行程序时，出现以下错误：
Traceback (most recent call last):
File "N:\pygame\working_on_30\main.py", line 164, in <module>
main()
File "N:\pygame\working_on_30\main.py", line 128, in main
all_sprites.update()
File "C:\Python 3.6\lib\site-packages\pygame\sprite.py", line 462, in update
s.update(*args)
File "N:\pygame\working_on_30\player.py", line 49, in update
if self.change_x > 0:
AttributeError: 'Player' object has no attribute 'change_x'
我尝试过改变各种各样的东西，却无法让它发挥作用。有人可以 a）解释错误 b）提供解决方案修复
答案 0 :(得分：0)
tl; dr - 将self.change_x = 0和self.change_y = 0添加到播放器类中的__init__。
您的播放器类有一个属性player.change_x，您可以在各个点分配，但不在您的init中。如果您在致电（例如）player.update()之前致电player.settopleft()，那么当update()方法执行第if self.change_x > 0:行时，由于self.change_x尚未定义而导致错误。
如果将self.change_x = 0添加到init，则确保始终为Player的实例设置变量。
按要求澄清：
您可以在player.py中定义类播放器。类方法之一是__init__。当您创建类Player的对象时（即当您的代码与main.py中的player=Player()类似）时，会调用__init__方法，您可以使用该方法确保所有对象都已正确初始化。
您的错误是由self.change_x未定义引起的，因此您应该在类的__init__中定义它，以确保永远不会发生此错误。我建议：
class Player(pygame.sprite.Sprite):
#-------------------Define Variables here
speed=0
#------------------Initialise Constructor
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image=pygame.image.load("player.png")
self.rect = self.image.get_rect()
# - CHANGE HERE! - sets initial speed to 0
self.change_x = 0
self.change_y = 0
# - END OF CHANGE
#--------------Fetch the rectangle object that has the dimensions of the image
self.rect =self.image.get_rect()
#---------------Define movement