pyqt5分离ui主线程到子线程

PyQt也给我们提供了这么一个类：QThread
通过继承它然后重写里面的 run()函数，就可以很容易的新建一个线程，达到多线程的任务。

子线程定义：

class myworkthread(QThread):
    #声明一个信号，同时返回一个int，什么都可以返回，参数是发送信号时附带参数的数据类型
    finishsignal=QtCore.pyqtSignal(int)
    def __init__(self,t):
        #t为创建该实例时传递进来的参数，这里需要初始化一下父类的初始化方法，不然会报错
        super(myworkthread, self).__init__()
        self.t=t
    #重写run函数，也就是子线程的执行函数
    def run(self):
        print('子线程开始')
        #模拟耗时的程序
        time.sleep(self.t)
        print('子线程结束')
        #子线程结束后，发送一个信号告诉主线程窗口，并附带参数100
        self.finishsignal.emit(100)

创建线程对象，并传入参数10

然后连接子线程的信号和槽函数

self.mywork=myworkthread(10)
self.mywork.finishsignal.connect(self.workend)

开启子线程

self.mywork.start()

通过开启子线程，可以让耗时的程序在子线程中进行，这样ui主线程就不会出现假卡死的情况了。

 def workend(self,ins):
        print('get=%d'%ins)
        self.open = 1

这个函数要定义一个参数传入接口，因为子线程发过来的信号夹带了一个参数

源代码：

ui界面：

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'PGUI.ui'
#
# Created by: PyQt5 UI code generator 5.15.1
#
# WARNING: Any manual changes made to this file will be lost when pyuic5 is
# run again.  Do not edit this file unless you know what you are doing.


from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 600)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.verticalLayout_2 = QtWidgets.QVBoxLayout(self.centralwidget)
        self.verticalLayout_2.setObjectName("verticalLayout_2")
        self.verticalLayout = QtWidgets.QVBoxLayout()
        self.verticalLayout.setObjectName("verticalLayout")
        self.horizontalLayout = QtWidgets.QHBoxLayout()
        self.horizontalLayout.setObjectName("horizontalLayout")
        self.comboBox = QtWidgets.QComboBox(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.comboBox.setFont(font)
        self.comboBox.setObjectName("comboBox")
        self.horizontalLayout.addWidget(self.comboBox)
        self.pushButton = QtWidgets.QPushButton(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.pushButton.setFont(font)
        self.pushButton.setObjectName("pushButton")
        self.horizontalLayout.addWidget(self.pushButton)
        self.verticalLayout.addLayout(self.horizontalLayout)
        self.horizontalLayout_2 = QtWidgets.QHBoxLayout()
        self.horizontalLayout_2.setObjectName("horizontalLayout_2")
        self.verticalLayout_3 = QtWidgets.QVBoxLayout()
        self.verticalLayout_3.setObjectName("verticalLayout_3")
        self.label_2 = QtWidgets.QLabel(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Preferred, QtWidgets.QSizePolicy.Fixed)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.label_2.sizePolicy().hasHeightForWidth())
        self.label_2.setSizePolicy(sizePolicy)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(24)
        self.label_2.setFont(font)
        self.label_2.setAlignment(QtCore.Qt.AlignCenter)
        self.label_2.setObjectName("label_2")
        self.verticalLayout_3.addWidget(self.label_2)
        self.lineEdit = QtWidgets.QLineEdit(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.lineEdit.setFont(font)
        self.lineEdit.setObjectName("lineEdit")
        self.verticalLayout_3.addWidget(self.lineEdit)
        self.horizontalLayout_2.addLayout(self.verticalLayout_3)
        self.verticalLayout_4 = QtWidgets.QVBoxLayout()
        self.verticalLayout_4.setObjectName("verticalLayout_4")
        self.label_3 = QtWidgets.QLabel(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Preferred, QtWidgets.QSizePolicy.Fixed)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.label_3.sizePolicy().hasHeightForWidth())
        self.label_3.setSizePolicy(sizePolicy)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(24)
        self.label_3.setFont(font)
        self.label_3.setAlignment(QtCore.Qt.AlignCenter)
        self.label_3.setObjectName("label_3")
        self.verticalLayout_4.addWidget(self.label_3)
        self.lineEdit_2 = QtWidgets.QLineEdit(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.lineEdit_2.setFont(font)
        self.lineEdit_2.setObjectName("lineEdit_2")
        self.verticalLayout_4.addWidget(self.lineEdit_2)
        self.horizontalLayout_2.addLayout(self.verticalLayout_4)
        self.verticalLayout.addLayout(self.horizontalLayout_2)
        self.horizontalLayout_3 = QtWidgets.QHBoxLayout()
        self.horizontalLayout_3.setObjectName("horizontalLayout_3")
        self.pushButton_3 = QtWidgets.QPushButton(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Preferred, QtWidgets.QSizePolicy.Fixed)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.pushButton_3.sizePolicy().hasHeightForWidth())
        self.pushButton_3.setSizePolicy(sizePolicy)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.pushButton_3.setFont(font)
        self.pushButton_3.setObjectName("pushButton_3")
        self.horizontalLayout_3.addWidget(self.pushButton_3)
        self.pushButton_2 = QtWidgets.QPushButton(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.pushButton_2.setFont(font)
        self.pushButton_2.setObjectName("pushButton_2")
        self.horizontalLayout_3.addWidget(self.pushButton_2)
        self.verticalLayout.addLayout(self.horizontalLayout_3)
        self.textBrowser = QtWidgets.QTextBrowser(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Expanding)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.textBrowser.sizePolicy().hasHeightForWidth())
        self.textBrowser.setSizePolicy(sizePolicy)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(16)
        self.textBrowser.setFont(font)
        self.textBrowser.setObjectName("textBrowser")
        self.verticalLayout.addWidget(self.textBrowser)
        self.verticalLayout_2.addLayout(self.verticalLayout)
        MainWindow.setCentralWidget(self.centralwidget)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.pushButton.setText(_translate("MainWindow", "开启串口"))
        self.label_2.setText(_translate("MainWindow", "电压设定值/kV"))
        self.label_3.setText(_translate("MainWindow", "电流设定值/mA"))
        self.pushButton_3.setText(_translate("MainWindow", "高压开关"))
        self.pushButton_2.setText(_translate("MainWindow", "读取电压电流"))

主代码：

from sys import argv,exit
import serial
from PyQt5 import QtCore
from PyQt5.QtCore import QTimer,QThread
from PyQt5.QtWidgets import QApplication, QMainWindow
from modbus_tk import modbus_rtu
import PGUI
import time


class my_mainwindow():
    def __init__(self):
        # PyQt5中，每个应用程序都必须实例化一个QApplication()：
        app = QApplication(argv)
        self.my_MainWindow = QMainWindow()
        self.my_ui = PGUI.Ui_MainWindow()
        self.my_ui.setupUi(self.my_MainWindow)
        ####################################################################
        self.open = 1
        self.timer = QTimer()
        self.timer.timeout.connect(self.showTime)
        self.timer.start(1000)
        self.mywork=myworkthread(10)
        self.mywork.finishsignal.connect(self.workend)
        #####################################################################
        self.my_MainWindow.show()
        exit(app.exec_())


    def workend(self,ins):
        print('get=%d'%ins)
        self.open = 1


    def showTime(self):
        if self.open==1:
            print('time')
            self.mywork.start()
            print('timeover')
            self.open=0

class myworkthread(QThread):
    #声明一个信号，同时返回一个int，什么都可以返回，参数是发送信号时附带参数的数据类型
    finishsignal=QtCore.pyqtSignal(int)
    def __init__(self,t):
        #t为创建该实例时传递进来的参数，这里需要初始化一下父类的初始化方法，不然会报错
        super(myworkthread, self).__init__()
        self.t=t
    #重写run函数，也就是子线程的执行函数
    def run(self):
        print('子线程开始')
        #模拟耗时的程序
        time.sleep(self.t)
        print('子线程结束')
        #子线程结束后，发送一个信号告诉主线程窗口，并附带参数100
        self.finishsignal.emit(100)


if __name__=="__main__":
    my_mainwindow()