Python模块间全局变量共享：理解import *的陷阱与正确实践

import pygame as Py

selectedSong = None

import globals  # 修改点：直接导入globals模块
import os
import pygame as Py # 假设Pygame在这里也被使用，或者从其他地方导入screen

# 假设screen对象在某个地方被定义并可访问，例如从main.py传入或作为真正的全局变量
# screen = Py.display.set_mode((800, 600)) # 示例，实际应在main.py中初始化

songs = os.listdir('./assets/songs')  

def generatePlaylist(font, event, screen): # 假设screen作为参数传入
    for index, song in enumerate(songs):
        rectIndex = Py.Rect(20, 25 + (50 * (index + 1)), 260, 40)
        rectIndexPosition = (20, 25 + (50 * (index + 1)))
        rectIndexWidth = 260
        rectIndexHeight = 40
        Py.draw.rect(screen, 'gray', rectIndex)
        text_surface = font.render(song, True, (0, 0, 0))
        text_rect = text_surface.get_rect(center=rectIndex.center)
        screen.blit(text_surface, text_rect)

        selected = selection(event, rectIndexPosition, rectIndexWidth, rectIndexHeight, song)
        if selected is not None:
            globals.selectedSong = selected  # 修改点：通过globals.selectedSong访问
            print(f"Playlist updated: {globals.selectedSong}") # 打印确认

        if index == len(songs) - 1:
            # ... 其他绘制逻辑 ...
            pass # 保持原样，或根据需要修正

def selection(event, rectIndexPosition, rectIndexWidth, rectIndexHeight, song):
    if event.type == Py.MOUSEBUTTONUP:
            if rectIndexPosition[0] <= event.pos[0] <= rectIndexPosition[0] + rectIndexWidth and \
               rectIndexPosition[1] <= event.pos[1] <= rectIndexPosition[1] + rectIndexHeight:
                return(song)
    return None    

import globals  # 修改点：直接导入globals模块
# from musicFunction import * # 保持不变，如果musicFunction中的变量没有类似问题
import pygame.mixer as mx # 假设mx在这里被使用

# 假设imagePlayPosition和imagePlay在某个地方被定义并可访问
# 例如：
# imagePlay = Py.image.load('path/to/play_button.png')
# imagePlayPosition = (x, y)

def play(): # 假设play函数定义在musicFunction.py中
    # 此处需要确保mx已初始化，例如在main.py中Py.mixer.init()
    mx.music.load(f'./assets/songs/{globals.selectedSong}') # 修改点：通过globals.selectedSong访问
    mx.music.play()

def playButton(event):
   if event.type == Py.MOUSEBUTTONDOWN:
      # 假设imagePlayPosition和imagePlay是可访问的
      if imagePlayPosition[0] <= event.pos[0] <= imagePlayPosition[0] + imagePlay.get_width() and \
         imagePlayPosition[1] <= event.pos[1] <= imagePlayPosition[1] + imagePlay.get_height():
         print(f"Play button clicked. Selected song: {globals.selectedSong}") # 修改点：通过globals.selectedSong访问
         if globals.selectedSong is not None: # 修改点：通过globals.selectedSong访问
            play()

import pygame as Py
from render import *
from buttonMusic import *
from playlist import *
import globals # 保持不变，但确认是import globals而非from globals import *
import os

Py.init()
Py.mixer.init() # 初始化混音器

# 假设screen对象在这里被初始化
screen = Py.display.set_mode((800, 600)) # 示例尺寸，根据实际需要调整

continuer = True
script_folder = os.path.dirname(os.path.abspath(__file__)) # 获取当前脚本所在目录
# 修正字体路径，确保它是相对于脚本的正确路径
font_path = os.path.join(script_folder, 'assets', 'font', 'Roboto-Black.ttf')
font = Py.font.Font(font_path, 18)

# 在这里初始化 imagePlay 和 imagePlayPosition，以便 buttonMusic.py 可以访问
# 或者将它们也放在 globals.py 中，然后通过 globals.imagePlay 访问
imagePlay = Py.image.load(os.path.join(script_folder, 'assets', 'play.png')) # 示例图片路径
imagePlayPosition = (100, 100) # 示例位置

while continuer:
    render(font, screen) # 假设render也需要screen
    for event in Py.event.get():
        if event.type == Py.QUIT:
            continuer = False
        generatePlaylist(font, event, screen) # 传入screen
        reculeButton(event)
        randomButton(event)
        playButton(event) # playButton现在会访问到正确的globals.selectedSong
        pauseButton(event)
        stopButton(event)
        advanceButton(event)
        loopButton(event)
        upButton(event)
        downButton(event)
        muteButton(event)
    Py.display.flip() # 更新屏幕显示

Py.quit()