import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5 import QtCore
import qdarkstyle
 
global sec
sec = 0
 
 
class WorkThread(QThread):
 trigger = pyqtSignal()
 
 def __int__(self):
  super(WorkThread, self).__init__()
 
 def run(self):
  for i in range(2000000000):
   pass
 
  # 循环完毕后发出信号
  self.trigger.emit()
 
def countTime():
 global sec
 sec += 1
 # LED显示数字+1
 lcdNumber.display(sec)
 
 
def work():
 # 计时器计时
 print("#30")
 timer.start(1000) # 将start写成statr居然不报错，但是找bug却找了半天
 # 计时开始
 workThread.start()
 # 当获得循环完毕的信号时，停止计时
 workThread.trigger.connect(timeStop)
 
 
def timeStop():
 print("#38")
 timer.stop()
 print("计时结束，共计用时：", lcdNumber.value())
 global sec
 sec = 0
 
 
if __name__ == "__main__":
 app = QApplication(sys.argv)
 top = QWidget()
 top.resize(300, 200)
 # 影藏边框
 top.setWindowFlags(QtCore.Qt.FramelessWindowHint)
 layout = QVBoxLayout(top)
 lcdNumber = QLCDNumber()
 layout.addWidget(lcdNumber)
 button = QPushButton("开始")
 layout.addWidget(button)
 
 timer = QTimer()
 workThread = WorkThread()
 button.clicked.connect(work)
 # 计时结束，触发countime
 timer.timeout.connect(countTime)
 # 进行渲染
 app.setStyleSheet(qdarkstyle.load_stylesheet_pyqt5())
 top.show()
 sys.exit(app.exec_())