import sys
from PyQt5.QtWidgets import QApplication, QWidget, QPushButton, QMessageBox, QLineEdit, QLabelclass Example(QWidget):def __init__(self):super().__init__()self.initUI()def initUI(self):self.setGeometry(300, 300, 400, 300)self.bt1 = QPushButton('登录', self)self.bt1.setGeometry(115, 150, 70 ,30)self.bt1.clicked.connect(self.showMessage)  # 相当于就是建立了一个click的处理事件self.usr = QLabel("用户：", self)   # 这里的好像都需要把self作为第二个参数传进去才能显示出来self.usr.setGeometry(50, 50, 30, 30)self.pwd = QLabel("密码：", self)self.pwd.setGeometry(50, 80, 30, 30)self.text1 = QLineEdit(self)#没有self的话连框都出不来self.text1.selectAll()self.text1.setFocus()self.text1.setGeometry(80, 50, 150 ,30)self.text2 = QLineEdit( self)self.text2.selectAll()self.text2.setFocus()self.text2.setGeometry(80, 80, 150 ,30)self.text2.setEchoMode(QLineEdit.Password)self.show()    def showMessage(self):acount = self.text1.text()  #这里text应该不需要转为字符串吧，返回的应该就是一个字符串。password= self.text2.text()print(acount)print(password)if len(password) == 0:QMessageBox.warning(self, "警告", "密码为空")else:QMessageBox.warning(self, "警告", "密码长度低于6位")if acount == "jackhe"  and  password == "123456" :QMessageBox.about(self, '','登录成功')else:QMessageBox.about(self, '','登录失败!') def closeEvent(self, event):reply = QMessageBox.question(self, '确认', '确认退出吗', QMessageBox.Yes | QMessageBox.No, QMessageBox.No)if reply == QMessageBox.Yes:event.accept()        else:event.ignore()if __name__ == '__main__':app = QApplication(sys.argv)ex = Example()sys.exit(app.exec_())

if __name__ == '__main__':app = QApplication(sys.argv)ex = Example()sys.exit(app.exec_())

def __init__(self):super().__init__()self.initUI()

        self.setGeometry(300, 300, 400, 300)self.bt1 = QPushButton('登录', self)self.bt1.setGeometry(115, 150, 70 ,30)self.bt1.clicked.connect(self.showMessage)  # 相当于就是建立了一个click的处理事件self.usr = QLabel("用户：", self)   # 这里的好像都需要把self作为第二个参数传进去才能显示出来self.usr.setGeometry(50, 50, 30, 30)self.pwd = QLabel("密码：", self)self.pwd.setGeometry(50, 80, 30, 30)self.text1 = QLineEdit(self)#没有self的话连框都出不来self.text1.selectAll()self.text1.setFocus()self.text1.setGeometry(80, 50, 150 ,30)self.text2 = QLineEdit( self)self.text2.selectAll()self.text2.setFocus()self.text2.setGeometry(80, 80, 150 ,30)self.text2.setEchoMode(QLineEdit.Password)

keyPressEvent(self, e)    按键时的监听，也就是监听你按下键盘的什么键。
mouseMoveEvent(self, event)   移动鼠标时的监听，比如获取鼠标当前所在所在位置信息
paintEvent(self, event)   重绘方法，这个我暂时理解位Java的重绘，也就是比如窗体的刷新，放大缩小等改变所导致的界面重绘（具体的话后面使用到再细说）
sender（）获取事件发送者的信息，从而根据源来判断反应。
s = Signal()
s.showmouse.connect(某个方法)  ：鼠标点击后运行的方法

def showMessage(self):acount = self.text1.text()  #这里text应该不需要转为字符串吧，返回的应该就是一个字符串。password= self.text2.text()print(acount)print(password)if len(password) == 0:QMessageBox.warning(self, "警告", "密码为空")else:QMessageBox.warning(self, "警告", "密码长度低于6位")if acount == "jackhe"  and  password == "123456" :QMessageBox.about(self, '','登录成功')else:QMessageBox.about(self, '','登录失败!') def closeEvent(self, event):reply = QMessageBox.question(self, '确认', '确认退出吗', QMessageBox.Yes | QMessageBox.No, QMessageBox.No)if reply == QMessageBox.Yes:event.accept()        else:event.ignore()

from PyQt5.QtCore import pyqtSlot
from PyQt5.QtWidgets import QMainWindowfrom .Ui_login import Ui_MainWindowclass Action(QMainWindow, Ui_MainWindow):"""Class documentation goes here."""def __init__(self, parent=None):"""Constructor@param parent reference to the parent widget@type QWidget"""super(Action, self).__init__(parent)self.setupUi(self)@pyqtSlot()def on_pushButton_clicked(self):"""Slot documentation goes here."""# TODO: not implemented yetraise NotImplementedError

if __name__ == "__main__":

# -*- coding: utf-8 -*-# Form implementation generated from reading ui file 'D:UsersDELLeric6workdirectoryqt3loginlogin.ui'
#
# Created by: PyQt5 UI code generator 5.6
#
# WARNING! All changes made in this file will be lost!from PyQt5 import QtCore, QtGui, QtWidgetsclass Ui_MainWindow(object):def setupUi(self, MainWindow):MainWindow.setObjectName("MainWindow")MainWindow.resize(800, 600)self.centralWidget = QtWidgets.QWidget(MainWindow)self.centralWidget.setObjectName("centralWidget")self.lineEdit = QtWidgets.QLineEdit(self.centralWidget)self.lineEdit.setGeometry(QtCore.QRect(260, 160, 113, 20))self.lineEdit.setObjectName("lineEdit")self.lineEdit_2 = QtWidgets.QLineEdit(self.centralWidget)self.lineEdit_2.setGeometry(QtCore.QRect(260, 190, 113, 20))self.lineEdit_2.setEchoMode(QtWidgets.QLineEdit.Password)self.lineEdit_2.setObjectName("lineEdit_2")self.label = QtWidgets.QLabel(self.centralWidget)self.label.setGeometry(QtCore.QRect(230, 160, 31, 21))self.label.setObjectName("label")self.label_2 = QtWidgets.QLabel(self.centralWidget)self.label_2.setGeometry(QtCore.QRect(230, 190, 54, 21))self.label_2.setObjectName("label_2")self.pushButton = QtWidgets.QPushButton(self.centralWidget)self.pushButton.setGeometry(QtCore.QRect(260, 230, 75, 23))self.pushButton.setObjectName("pushButton")MainWindow.setCentralWidget(self.centralWidget)self.retranslateUi(MainWindow)QtCore.QMetaObject.connectSlotsByName(MainWindow)def retranslateUi(self, MainWindow):_translate = QtCore.QCoreApplication.translateMainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))self.label.setText(_translate("MainWindow", "账号"))self.label_2.setText(_translate("MainWindow", "密码"))self.pushButton.setText(_translate("MainWindow", "登录"))if __name__ == "__main__":import sysapp = QtWidgets.QApplication(sys.argv)MainWindow = QtWidgets.QMainWindow()ui = Ui_MainWindow()ui.setupUi(MainWindow)MainWindow.show()sys.exit(app.exec_())

# -*- coding: utf-8 -*-"""
Module implementing Action.
"""
import sys
from PyQt5.QtCore import pyqtSlot
from PyQt5.QtWidgets import *from Ui_login import Ui_MainWindowclass Action(QMainWindow, Ui_MainWindow):def __init__(self, parent=None):super(Action, self).__init__(parent)self.setupUi(self)self.show()@pyqtSlot()def on_pushButton_clicked(self):acount = self.lineEdit.text()  #这里text应该不需要转为字符串吧，返回的应该就是一个字符串。password= self.lineEdit_2.text()print(acount)print(password)if len(password) == 0:QMessageBox.warning(self, "警告", "密码为空")else:QMessageBox.warning(self, "警告", "密码长度低于6位")if acount == "jackhe"  and  password == "123456" :QMessageBox.about(self, '','登录成功')else:QMessageBox.about(self, '','登录失败!') def closeEvent(self, event):reply = QMessageBox.question(self, '确认', '确认退出吗', QMessageBox.Yes | QMessageBox.No, QMessageBox.No)if reply == QMessageBox.Yes:event.accept()        else:event.ignore()
if __name__ == "__main__":app = QApplication(sys.argv)action = Action()sys.exit(app.exec_())