...
  def downfile(self,file, url):
  print("开始下载：", file, url)
  try:
   r = requests.get(url, stream=True)
   with open(file, 'wb') as fd:
    for chunk in r.iter_content():
     fd.write(chunk)
     QApplication.processEvents()
  except Exception as e:
   print("下载失败了", e)
 ...

from PyQt5.QtCore import QThread, pyqtSignal
 
class interface(QMainWindow, Ui_MainWindow):
 """
 Class documentation goes here.
 """
 def xxxx():
  "此处省略无数行代码......"
  self.Work()
 
 def Work(self):
  self.thread = RunThread()
  self.thread.start()
 
class RunThread(QThread):
 # python3,pyqt5与之前的版本有些不一样
 # 通过类成员对象定义信号对象
 # _signal = pyqtSignal(str)
 
 trigger = pyqtSignal()
 
 def __init__(self, parent=None):
  super(RunThread, self).__init__()
 
 def __del__(self):
  self.wait()
 
 def run(self):
  # 处理你要做的业务逻辑，这里是通过一个回调来处理数据，这里的逻辑处理写自己的方法
  dlg.Config['user'] = dlg.check_account['account']
  dlg.Config['passwd'] = dlg.check_account['password']
  dlg.Config['jk'] = 'http://xxx.com'
  if dlg.num != 1:
   dlg.operato.config_item(dlg.Config, dlg.wx_update) # 初始化配置
  else:
   dlg.operato.config_item(dlg.Config, dlg.wx_create) # 初始化配置
 
  self.trigger.emit()

import sys
import asyncio
import time
 
from PyQt5.QtWidgets import QApplication, QProgressBar
from quamash import QEventLoop, QThreadExecutor
 
app = QApplication(sys.argv)
loop = QEventLoop(app)
asyncio.set_event_loop(loop) # NEW must set the event loop
 
progress = QProgressBar()
progress.setRange(0, 99)
progress.show()
 
async def master():
 await first_50()
 with QThreadExecutor(1) as exec:
  await loop.run_in_executor(exec, last_50)
 # TODO announce completion?
 
async def first_50():
 for i in range(50):
  progress.setValue(i)
  await asyncio.sleep(.1)
 
def last_50():
 for i in range(50,100):
  loop.call_soon_threadsafe(progress.setValue, i)
  time.sleep(.1)
 
with loop: ## context manager calls .close() when loop completes, and releases all resources
 loop.run_until_complete(master())