【数据库实验】《小型MIS的开发》PyQt5 开发民航票务管理系统

浅浅的花香味﹌ 2023-02-18 03:25 17阅读 0赞

### PyQt5 开发 民航票务管理系统 ###

*  为什么要拿 Python 做呢？
 *  学习一天的知识点
 *  开发环境 与 项目整体结构
 *  数据库建表
 *   *  用户表的 SQL
     *  航班信息表的 SQL
 *  界面代码
 *   *  主界面：hello.py
     *  登录界面：login.py
     *  操作界面：operate.py
 *  逻辑代码 app.py
 *  项目演示

> 这份 Java 是我的实验的：[《小型MIS的开发》— Spring + Mybatis + JavaFx 开发 民航票务管理系统][MIS_ Spring _ Mybatis _ JavaFx _]

下面这份 Python 版是帮女朋友写的！

# 为什么要拿 Python 做呢？ #

这两天正好在下大雨，昨天我把自己的软件 + 报告写完后，准备开始帮女朋友写，原本打算在我的代码的基础上改改 UI 和 逻辑什么的，就可以搞定了；这是原计划，毕竟用 JavaFx 开发确实是效率高啊！

但是昨天的大雨让我没法去自习室。。。我的考研相关的书都在自习室，既然只能呆在宿舍。。那不如学点新东西把，于是我选择了 Python + Qt 制作图形化界面，就当增加一下自己的技术栈。。

# 学习一天的知识点 #

如果是真心的想学习一下的话，可以看看这几篇文章，这些是我将这个项目要用到的知识点模块化记录了一下：

首先是 **PyQt5 的 安装 与 入门教程**：[【PyQt5】PyQt5 安装 以及使用 designer 开发 python GUI 界面][PyQt5_PyQt5 _ _ designer _ python GUI]

然后是安装时可能遇到的问题：[PyQt5: This application failed to start because it could not find or load the Qt platform plugin][PyQt5_ This application failed to start because it could not find or load the Qt platform plugin]

完成上面的 安装 与 入门 以后可以正式开始写我们这个项目了；  
然后需要了解的是 **页面跳转** 相关的知识：[【PyQt5】designer 页面点击按钮跳转页面][PyQt5_designer]

了解这个以后，就可以完整的搭建出一个完整的 包含点击按钮进行跳转的 界面了；但是此时界面上是没有数据的，因此下一步需要学习的是 **Python 连接数据库** 相关知识：[【PyQt5】PyMySQL 连接 MySQL数据库][PyQt5_PyMySQL _ MySQL]

学会与数据库打交道以后，我们只要再学一个 **PyQt5 的组件——tableWidget** 就可以完成我们这次实验了：[【PyQt5】连接 mysql 查询数据 并显示在 tableWidget 表格][PyQt5_ mysql _ _ tableWidget]

以上是如果你想靠自己的实力完成这次实验需要掌握的知识点。

# 开发环境 与 项目整体结构 #

我的开发环境是：

*  PyQt 5
 *  Python 3.8
 *  VsCode
 *  MySQL 5.7

项目整体结构：  
![在这里插入图片描述][20200616174357115.png]  
ui 目录下存放 `.ui` 文件，这个是由 qt designer 设计出来的界面文件，我们可以通过 **pyuic5** 将它们转化为 Python 代码，所以 `hello.ui` —> `hello.py`、`login.ui` —> `login.py`、`operate.ui` —> `operate.py`，一一对应。

顺带一提，代码的编译运行 是不需要 `.ui` 文件的，只有当你想要修改界面时候，才会去动他。

至于 `app.py`，那就是我们的核心逻辑文件了，如果想要看懂这里的东西就需要去学习上面列出的知识点啦！

# 数据库建表 #

需要两张表：

*  用户表 user
 *  航班信息表 flight

命令行登录 MySQL:

mysql -u root -p
    > 输入密码: 1234

建立一个数据库：`sxn210224`，并进入：

CREATE DATABASE sxn210224;
    USE sxn210224;

下面开始建表：

## 用户表的 SQL ##

SET FOREIGN_KEY_CHECKS=0;
    
    -- ----------------------------
    -- Table structure for user
    -- ----------------------------
    DROP TABLE IF EXISTS `user`;
    CREATE TABLE `user` (
      `u_id` varchar(8) NOT NULL,
      `u_username` varchar(50) DEFAULT NULL,
      `u_password` varchar(50) DEFAULT NULL,
      PRIMARY KEY (`u_id`)
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
    
    -- ----------------------------
    -- Records of user
    -- ----------------------------
    INSERT INTO `user` VALUES ('17210224', 'luzhenyu', '123456');
    INSERT INTO `user` VALUES ('17210309', 'hanlei', '123456');

## 航班信息表的 SQL ##

SET FOREIGN_KEY_CHECKS=0;
    
    -- ----------------------------
    -- Table structure for flight
    -- ----------------------------
    DROP TABLE IF EXISTS `flight`;
    CREATE TABLE `flight` (
      `f_id` char(8) NOT NULL,
      `f_src` varchar(15) DEFAULT NULL,
      `f_des` varchar(15) DEFAULT NULL,
      `f_date` date NOT NULL,
      `f_start_time` char(6) DEFAULT NULL,
      `f_end_time` char(6) DEFAULT NULL,
      `f_remain_seats` int(4) DEFAULT NULL,
      `f_fares` float(8,0) DEFAULT NULL,
      `f_discount_nums` float(8,0) DEFAULT NULL,
      `f_discount` float(8,0) DEFAULT NULL,
      `f_subordinate_company` varchar(20) DEFAULT NULL,
      PRIMARY KEY (`f_id`,`f_date`)
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
    
    -- ----------------------------
    -- Records of flight
    -- ----------------------------
    INSERT INTO `flight` VALUES ('F001', '扬州', '苏州', '2012-12-12', '15:30', '14:20', '5', '99', '5', '1', '振宇有限公司');
    INSERT INTO `flight` VALUES ('F002', '扬州', '苏州', '2012-12-13', '12:20', '15:50', '20', '99', '5', '1', '振宇有限公司');
    INSERT INTO `flight` VALUES ('F003', '扬州', '北京', '2012-12-13', '12:20', '17:50', '4', '99', '5', '1', '振宇有限公司');
    INSERT INTO `flight` VALUES ('F004', '扬州', '泰国', '2012-12-13', '7:20', '8:50', '2', '99', '5', '1', '振宇有限公司');
    INSERT INTO `flight` VALUES ('F005', '扬州', '广州', '2012-12-14', '5:20', '14:50', '40', '99', '5', '1', '振宇有限公司');

# 界面代码 #

注意，我们的界面都是通过 Qt designer 拖拽制作的 `.ui` 文件，再通过 **pyuic5** 工具转为 `.py` 文件

简单起见，总共就只有三个界面文件：

*  主界面 `hello.py`
 *  登陆界面 `login.py`
 *  操作界面 `operate.py`

## 主界面：hello.py ##

## 登录界面：login.py ##

from PyQt5 import QtCore, QtGui, QtWidgets
    
    class Ui_MainWindow(object):
        def setupUi(self, MainWindow):
            MainWindow.setObjectName("MainWindow")
            MainWindow.resize(510, 290)
            self.centralwidget = QtWidgets.QWidget(MainWindow)
            self.centralwidget.setObjectName("centralwidget")
            self.gridLayout_2 = QtWidgets.QGridLayout(self.centralwidget)
            self.gridLayout_2.setObjectName("gridLayout_2")
            self.label = QtWidgets.QLabel(self.centralwidget)
            sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Preferred)
            sizePolicy.setHorizontalStretch(0)
            sizePolicy.setVerticalStretch(0)
            sizePolicy.setHeightForWidth(self.label.sizePolicy().hasHeightForWidth())
            self.label.setSizePolicy(sizePolicy)
            font = QtGui.QFont()
            font.setPointSize(25)
            self.label.setFont(font)
            self.label.setAlignment(QtCore.Qt.AlignCenter)
            self.label.setObjectName("label")
            self.gridLayout_2.addWidget(self.label, 0, 0, 1, 1)
            self.gridLayout = QtWidgets.QGridLayout()
            self.gridLayout.setContentsMargins(-1, -1, -1, 15)
            self.gridLayout.setSpacing(20)
            self.gridLayout.setObjectName("gridLayout")
            self.label_2 = QtWidgets.QLabel(self.centralwidget)
            sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Preferred)
            sizePolicy.setHorizontalStretch(0)
            sizePolicy.setVerticalStretch(0)
            sizePolicy.setHeightForWidth(self.label_2.sizePolicy().hasHeightForWidth())
            self.label_2.setSizePolicy(sizePolicy)
            font = QtGui.QFont()
            font.setPointSize(12)
            self.label_2.setFont(font)
            self.label_2.setObjectName("label_2")
            self.gridLayout.addWidget(self.label_2, 0, 0, 1, 1)
            self.userText = QtWidgets.QLineEdit(self.centralwidget)
            sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Fixed)
            sizePolicy.setHorizontalStretch(0)
            sizePolicy.setVerticalStretch(0)
            sizePolicy.setHeightForWidth(self.userText.sizePolicy().hasHeightForWidth())
            self.userText.setSizePolicy(sizePolicy)
            font = QtGui.QFont()
            font.setPointSize(12)
            self.userText.setFont(font)
            self.userText.setAlignment(QtCore.Qt.AlignCenter)
            self.userText.setObjectName("userText")
            self.gridLayout.addWidget(self.userText, 0, 1, 1, 1)
            self.label_3 = QtWidgets.QLabel(self.centralwidget)
            sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Preferred)
            sizePolicy.setHorizontalStretch(0)
            sizePolicy.setVerticalStretch(0)
            sizePolicy.setHeightForWidth(self.label_3.sizePolicy().hasHeightForWidth())
            self.label_3.setSizePolicy(sizePolicy)
            font = QtGui.QFont()
            font.setPointSize(12)
            self.label_3.setFont(font)
            self.label_3.setObjectName("label_3")
            self.gridLayout.addWidget(self.label_3, 1, 0, 1, 1)
            self.pwdText = QtWidgets.QLineEdit(self.centralwidget)
            sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Fixed)
            sizePolicy.setHorizontalStretch(0)
            sizePolicy.setVerticalStretch(0)
            sizePolicy.setHeightForWidth(self.pwdText.sizePolicy().hasHeightForWidth())
            self.pwdText.setSizePolicy(sizePolicy)
            font = QtGui.QFont()
            font.setPointSize(12)
            self.pwdText.setFont(font)
            self.pwdText.setAlignment(QtCore.Qt.AlignCenter)
            self.pwdText.setObjectName("pwdText")
            self.gridLayout.addWidget(self.pwdText, 1, 1, 1, 1)
            self.gridLayout_2.addLayout(self.gridLayout, 1, 0, 1, 1)
            self.horizontalLayout = QtWidgets.QHBoxLayout()
            self.horizontalLayout.setContentsMargins(-1, -1, -1, 12)
            self.horizontalLayout.setSpacing(20)
            self.horizontalLayout.setObjectName("horizontalLayout")
            self.okButton = QtWidgets.QPushButton(self.centralwidget)
            sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Fixed)
            sizePolicy.setHorizontalStretch(0)
            sizePolicy.setVerticalStretch(0)
            sizePolicy.setHeightForWidth(self.okButton.sizePolicy().hasHeightForWidth())
            self.okButton.setSizePolicy(sizePolicy)
            font = QtGui.QFont()
            font.setPointSize(12)
            self.okButton.setFont(font)
            self.okButton.setObjectName("okButton")
            self.horizontalLayout.addWidget(self.okButton)
            self.cancelButton = QtWidgets.QPushButton(self.centralwidget)
            sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Fixed)
            sizePolicy.setHorizontalStretch(0)
            sizePolicy.setVerticalStretch(0)
            sizePolicy.setHeightForWidth(self.cancelButton.sizePolicy().hasHeightForWidth())
            self.cancelButton.setSizePolicy(sizePolicy)
            font = QtGui.QFont()
            font.setPointSize(12)
            self.cancelButton.setFont(font)
            self.cancelButton.setObjectName("cancelButton")
            self.horizontalLayout.addWidget(self.cancelButton)
            self.gridLayout_2.addLayout(self.horizontalLayout, 2, 0, 1, 1)
            MainWindow.setCentralWidget(self.centralwidget)
            self.statusbar = QtWidgets.QStatusBar(MainWindow)
            self.statusbar.setObjectName("statusbar")
            MainWindow.setStatusBar(self.statusbar)
    
            self.retranslateUi(MainWindow)
            QtCore.QMetaObject.connectSlotsByName(MainWindow)
    
        def retranslateUi(self, MainWindow):
            _translate = QtCore.QCoreApplication.translate
            MainWindow.setWindowTitle(_translate("MainWindow", " 登陆界面"))
            self.label.setText(_translate("MainWindow", "请输入用户信息"))
            self.label_2.setText(_translate("MainWindow", "用户名"))
            self.label_3.setText(_translate("MainWindow", "密码"))
            self.okButton.setText(_translate("MainWindow", "确定"))
            self.cancelButton.setText(_translate("MainWindow", "取消"))

## 操作界面：operate.py ##

from PyQt5 import QtCore, QtGui, QtWidgets
    
    
    class Ui_MainWindow(object):
        def setupUi(self, MainWindow):
            MainWindow.setObjectName("MainWindow")
            MainWindow.resize(750, 460)
            self.centralwidget = QtWidgets.QWidget(MainWindow)
            self.centralwidget.setObjectName("centralwidget")
            self.tableWidget = QtWidgets.QTableWidget(self.centralwidget)
            self.tableWidget.setGeometry(QtCore.QRect(0, 90, 731, 161))
            self.tableWidget.setObjectName("tableWidget")
            self.tableWidget.setColumnCount(11)
            self.tableWidget.setRowCount(9)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(0, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(1, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(2, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(3, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(4, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(5, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(6, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(7, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setVerticalHeaderItem(8, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(0, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(1, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(2, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(3, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(4, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(5, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(6, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(7, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(8, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(9, item)
            item = QtWidgets.QTableWidgetItem()
            self.tableWidget.setHorizontalHeaderItem(10, item)
            self.layoutWidget = QtWidgets.QWidget(self.centralwidget)
            self.layoutWidget.setGeometry(QtCore.QRect(100, 380, 208, 35))
            self.layoutWidget.setObjectName("layoutWidget")
            self.horizontalLayout = QtWidgets.QHBoxLayout(self.layoutWidget)
            self.horizontalLayout.setContentsMargins(0, 0, 0, 0)
            self.horizontalLayout.setSpacing(20)
            self.horizontalLayout.setObjectName("horizontalLayout")
            self.pushButton = QtWidgets.QPushButton(self.layoutWidget)
            font = QtGui.QFont()
            font.setPointSize(13)
            self.pushButton.setFont(font)
            self.pushButton.setObjectName("pushButton")
            self.horizontalLayout.addWidget(self.pushButton)
            self.exitButton = QtWidgets.QPushButton(self.layoutWidget)
            font = QtGui.QFont()
            font.setPointSize(13)
            self.exitButton.setFont(font)
            self.exitButton.setObjectName("exitButton")
            self.horizontalLayout.addWidget(self.exitButton)
            self.layoutWidget1 = QtWidgets.QWidget(self.centralwidget)
            self.layoutWidget1.setGeometry(QtCore.QRect(50, 290, 241, 74))
            self.layoutWidget1.setObjectName("layoutWidget1")
            self.verticalLayout = QtWidgets.QVBoxLayout(self.layoutWidget1)
            self.verticalLayout.setContentsMargins(0, 0, 0, 0)
            self.verticalLayout.setObjectName("verticalLayout")
            self.horizontalLayout_3 = QtWidgets.QHBoxLayout()
            self.horizontalLayout_3.setSpacing(20)
            self.horizontalLayout_3.setObjectName("horizontalLayout_3")
            self.label = QtWidgets.QLabel(self.layoutWidget1)
            font = QtGui.QFont()
            font.setPointSize(15)
            self.label.setFont(font)
            self.label.setObjectName("label")
            self.horizontalLayout_3.addWidget(self.label)
            self.lineEdit = QtWidgets.QLineEdit(self.layoutWidget1)
            font = QtGui.QFont()
            font.setPointSize(15)
            self.lineEdit.setFont(font)
            self.lineEdit.setObjectName("lineEdit")
            self.horizontalLayout_3.addWidget(self.lineEdit)
            self.verticalLayout.addLayout(self.horizontalLayout_3)
            self.horizontalLayout_2 = QtWidgets.QHBoxLayout()
            self.horizontalLayout_2.setSpacing(20)
            self.horizontalLayout_2.setObjectName("horizontalLayout_2")
            self.label_2 = QtWidgets.QLabel(self.layoutWidget1)
            font = QtGui.QFont()
            font.setPointSize(15)
            self.label_2.setFont(font)
            self.label_2.setObjectName("label_2")
            self.horizontalLayout_2.addWidget(self.label_2)
            self.dateEdit = QtWidgets.QDateEdit(self.layoutWidget1)
            sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Expanding)
            sizePolicy.setHorizontalStretch(0)
            sizePolicy.setVerticalStretch(0)
            sizePolicy.setHeightForWidth(self.dateEdit.sizePolicy().hasHeightForWidth())
            self.dateEdit.setSizePolicy(sizePolicy)
            font = QtGui.QFont()
            font.setPointSize(13)
            self.dateEdit.setFont(font)
            self.dateEdit.setObjectName("dateEdit")
            self.horizontalLayout_2.addWidget(self.dateEdit)
            self.verticalLayout.addLayout(self.horizontalLayout_2)
            self.layoutWidget2 = QtWidgets.QWidget(self.centralwidget)
            self.layoutWidget2.setGeometry(QtCore.QRect(200, 40, 321, 41))
            self.layoutWidget2.setObjectName("layoutWidget2")
            self.horizontalLayout_4 = QtWidgets.QHBoxLayout(self.layoutWidget2)
            self.horizontalLayout_4.setContentsMargins(0, 0, 0, 0)
            self.horizontalLayout_4.setSpacing(20)
            self.horizontalLayout_4.setObjectName("horizontalLayout_4")
            self.pushButton_3 = QtWidgets.QPushButton(self.layoutWidget2)
            self.pushButton_3.setObjectName("pushButton_3")
            self.horizontalLayout_4.addWidget(self.pushButton_3)
            self.pushButton_4 = QtWidgets.QPushButton(self.layoutWidget2)
            self.pushButton_4.setObjectName("pushButton_4")
            self.horizontalLayout_4.addWidget(self.pushButton_4)
            self.pushButton_5 = QtWidgets.QPushButton(self.layoutWidget2)
            self.pushButton_5.setObjectName("pushButton_5")
            self.horizontalLayout_4.addWidget(self.pushButton_5)
            MainWindow.setCentralWidget(self.centralwidget)
            self.statusbar = QtWidgets.QStatusBar(MainWindow)
            self.statusbar.setObjectName("statusbar")
            MainWindow.setStatusBar(self.statusbar)
    
            self.retranslateUi(MainWindow)
            QtCore.QMetaObject.connectSlotsByName(MainWindow)
    
        def retranslateUi(self, MainWindow):
            _translate = QtCore.QCoreApplication.translate
            MainWindow.setWindowTitle(_translate("MainWindow", "操作界面"))
            item = self.tableWidget.verticalHeaderItem(0)
            item.setText(_translate("MainWindow", "1"))
            item = self.tableWidget.verticalHeaderItem(1)
            item.setText(_translate("MainWindow", "2"))
            item = self.tableWidget.verticalHeaderItem(2)
            item.setText(_translate("MainWindow", "3"))
            item = self.tableWidget.verticalHeaderItem(3)
            item.setText(_translate("MainWindow", "4"))
            item = self.tableWidget.verticalHeaderItem(4)
            item.setText(_translate("MainWindow", "5"))
            item = self.tableWidget.verticalHeaderItem(5)
            item.setText(_translate("MainWindow", "6"))
            item = self.tableWidget.verticalHeaderItem(6)
            item.setText(_translate("MainWindow", "7"))
            item = self.tableWidget.verticalHeaderItem(7)
            item.setText(_translate("MainWindow", "8"))
            item = self.tableWidget.verticalHeaderItem(8)
            item.setText(_translate("MainWindow", "9"))
            item = self.tableWidget.horizontalHeaderItem(0)
            item.setText(_translate("MainWindow", "航班号"))
            item = self.tableWidget.horizontalHeaderItem(1)
            item.setText(_translate("MainWindow", "起点"))
            item = self.tableWidget.horizontalHeaderItem(2)
            item.setText(_translate("MainWindow", "终点"))
            item = self.tableWidget.horizontalHeaderItem(3)
            item.setText(_translate("MainWindow", "日期"))
            item = self.tableWidget.horizontalHeaderItem(4)
            item.setText(_translate("MainWindow", "起飞时刻"))
            item = self.tableWidget.horizontalHeaderItem(5)
            item.setText(_translate("MainWindow", "到达时刻"))
            item = self.tableWidget.horizontalHeaderItem(6)
            item.setText(_translate("MainWindow", "票价"))
            item = self.tableWidget.horizontalHeaderItem(7)
            item.setText(_translate("MainWindow", "折扣票数"))
            item = self.tableWidget.horizontalHeaderItem(8)
            item.setText(_translate("MainWindow", "剩余座位数"))
            item = self.tableWidget.horizontalHeaderItem(9)
            item.setText(_translate("MainWindow", "折扣率"))
            item = self.tableWidget.horizontalHeaderItem(10)
            item.setText(_translate("MainWindow", "航班所属航空公司"))
            self.pushButton.setText(_translate("MainWindow", "查询"))
            self.exitButton.setText(_translate("MainWindow", "退出"))
            self.label.setText(_translate("MainWindow", "航班号"))
            self.label_2.setText(_translate("MainWindow", "日期"))
            self.pushButton_3.setText(_translate("MainWindow", "增加"))
            self.pushButton_4.setText(_translate("MainWindow", "修改"))
            self.pushButton_5.setText(_translate("MainWindow", "删除"))

# 逻辑代码 app.py #

![在这里插入图片描述][20200616192443600.png]  
将以上的界面代码 与 下面的逻辑代码放在一个文件下就可以运行啦！（需要 PyQt 环境）  
环境安装可以看这个：[【PyQt5】PyQt5 安装 以及使用 designer 开发 python GUI 界面][PyQt5_PyQt5 _ _ designer _ python GUI]

import sys
    from PyQt5 import QtCore, QtWidgets, QtCore
    import pymysql
    
    from hello import Ui_MainWindow as Hello_Ui 
    from login import Ui_MainWindow as Login_Ui
    from operate import Ui_MainWindow as Operate_Ui
    
    # 主窗口
    class HelloWindow(QtWidgets.QMainWindow, Hello_Ui):
        switch_window1 = QtCore.pyqtSignal()
        switch_window2 = QtCore.pyqtSignal()
        def __init__(self):
            super(HelloWindow, self).__init__()
            self.setupUi(self)
            self.queryButton.clicked.connect(self.goOperate)
            self.manageButton.clicked.connect(self.goLogin)
        def goLogin(self):
            self.switch_window1.emit()
        def goOperate(self):
            self.switch_window2.emit()
    
    # 登录窗口
    class LoginWindow(QtWidgets.QMainWindow, Login_Ui):
        switch_window1 = QtCore.pyqtSignal()
        switch_window2 = QtCore.pyqtSignal()
        def __init__(self):
            super(LoginWindow, self).__init__()
            self.setupUi(self)
            self.okButton.clicked.connect(self.ok)
            self.cancelButton.clicked.connect(self.cancel)
            
    
        def ok(self):
            username = self.userText.text()
            password = self.pwdText.text()
            # 创建数据库连接
            conn = pymysql.connect(
                host = '127.0.0.1', # 连接主机, 默认127.0.0.1 
                user = 'root',      # 用户名
                passwd = '1234',    # 密码
                port = 3306,        # 端口，默认为3306
                db = 'sxn210224',   # 数据库名称
                charset = 'utf8'    # 字符编码
            )
            # 生成游标对象 cursor
            cursor = conn.cursor()
            if (cursor.execute("SELECT * FROM user WHERE u_username='%s' AND u_password='%s'" %(username, password))): 
                self.switch_window1.emit()
            else:
                print("密码错误！！")
            cursor.close()
            conn.close()
    
        def cancel(self):
            self.switch_window2.emit()
        
    # 操作窗口
    class OperateWindow(QtWidgets.QMainWindow, Operate_Ui):
        def __init__(self):
            super(OperateWindow, self).__init__()
            self.setupUi(self)
            self.exitButton.clicked.connect(self.exit)
    
             # 数据库连接对象
            conn = pymysql.connect(host='localhost', port=3306, user='root', password="1234", db="sxn210224")
            # 游标对象
            cur = conn.cursor()
            
            # 查询的sql语句
            sql = "SELECT * FROM flight"
            cur.execute(sql)
            # 获取查询到的数据, 是以二维元组的形式存储的, 所以读取需要使用 data[i][j] 下标定位
            data = cur.fetchall()
            # 打印测试
            print(data)
    
            # 遍历二维元组, 将 id 和 name 显示到界面表格上
            x = 0
            for i in data:
                y = 0
                for j in i:
                    self.tableWidget.setItem(x, y, QtWidgets.QTableWidgetItem(str(data[x][y])))
                    y = y + 1
                x = x + 1
    
            cur.close()
            conn.close()
        
        def exit(self):
            sys.exit(0)
    
    
    # 利用一个控制器来控制页面的跳转
    class Controller:
        def __init__(self):
            self.hello = HelloWindow()
            self.login = LoginWindow()
            self.operate = OperateWindow()
        def show_hello(self):
            self.hello = HelloWindow()
            self.hello.switch_window1.connect(self.show_login)
            self.hello.switch_window2.connect(self.show_operate)
            self.hello.show()
            self.login.close()
            self.operate.close()
        def show_login(self):
            self.login = LoginWindow()
            self.login.switch_window1.connect(self.show_operate)
            self.login.switch_window2.connect(self.show_hello)
            self.login.show()
            self.hello.close()
            self.operate.close()
        def show_operate(self):
            self.operate = OperateWindow()
            self.operate.show()
            self.hello.close()
            self.login.close()
    
    def main():
        app = QtWidgets.QApplication(sys.argv)
        controller = Controller()
        controller.show_hello()
        sys.exit(app.exec_())
    
    if __name__ == '__main__':
        main()

# 项目演示 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ_size_16_color_FFFFFF_t_70]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ_size_16_color_FFFFFF_t_70 1]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ_size_16_color_FFFFFF_t_70 2]

[MIS_ Spring _ Mybatis _ JavaFx _]: https://blog.csdn.net/weixin_43734095/article/details/106594631
[PyQt5_PyQt5 _ _ designer _ python GUI]: https://blog.csdn.net/weixin_43734095/article/details/106761680
[PyQt5_ This application failed to start because it could not find or load the Qt platform plugin]: https://blog.csdn.net/weixin_43734095/article/details/106763077
[PyQt5_designer]: https://blog.csdn.net/weixin_43734095/article/details/106783108
[PyQt5_PyMySQL _ MySQL]: https://blog.csdn.net/weixin_43734095/article/details/106785024
[PyQt5_ mysql _ _ tableWidget]: https://blog.csdn.net/weixin_43734095/article/details/106789271
[20200616174357115.png]: https://img-blog.csdnimg.cn/20200616174357115.png
[20200616192443600.png]: https://img-blog.csdnimg.cn/20200616192443600.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200616173307760.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20200616173318741.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ_size_16_color_FFFFFF_t_70 2]: https://img-blog.csdnimg.cn/20200616173342861.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzczNDA5NQ==,size_16,color_FFFFFF,t_70