# coding=utf-8 
__author__ = 'a359680405'  
from PyQt5.QtCore import * 
from PyQt5.QtGui import * 
from PyQt5.QtWidgets import *  
global sec 
sec=0 
def setTime(): 
  global sec 
  sec+=1 
  lcdNumber.display(sec)     #LED显示数字+1  
def work(): 
  timer.start(1000)        #计时器每秒计数 
  for i in range(2000000000): 
    pass 
  timer.stop()  
app=QApplication([]) 
top=QWidget() 
layout=QVBoxLayout(top)       #垂直布局类QVBoxLayout； 
lcdNumber=QLCDNumber()       #加个显示屏 
layout.addWidget(lcdNumber) 
button=QPushButton("测试") 
layout.addWidget(button)  
timer=QTimer() 
timer.timeout.connect(setTime)   #每次计时结束，触发setTime 
button.clicked.connect(work)  
top.show() 
app.exec() 

# coding=utf-8 
__author__ = 'a359680405'  
from PyQt5.QtCore import * 
from PyQt5.QtGui import * 
from PyQt5.QtWidgets import *  
global sec 
sec=0 
class WorkThread(QThread): 
  trigger = pyqtSignal() 
  def __int__(self): 
    super(WorkThread,self).__init__() 
 
  def run(self): 
    for i in range(203300030): 
      pass 
    self.trigger.emit()     #循环完毕后发出信号 
 
def countTime(): 
  global sec 
  sec+=1 
  lcdNumber.display(sec)     #LED显示数字+1 
 
def work(): 
  timer.start(1000)        #计时器每秒计数 
  workThread.start()       #计时开始 
  workThread.trigger.connect(timeStop)  #当获得循环完毕的信号时，停止计数 
 
def timeStop(): 
  timer.stop() 
  print("运行结束用时",lcdNumber.value()) 
  global sec 
  sec=0  
app=QApplication([]) 
top=QWidget() 
layout=QVBoxLayout(top)       #垂直布局类QVBoxLayout； 
lcdNumber=QLCDNumber()       #加个显示屏 
layout.addWidget(lcdNumber) 
button=QPushButton("测试") 
layout.addWidget(button)  
timer=QTimer() 
workThread=WorkThread() 
button.clicked.connect(work) 
timer.timeout.connect(countTime)   #每次计时结束，触发setTime  
top.show() 
app.exec()