main.py

from PyQt6.QtCore import Qt
from PyQt6.QtGui import QAction, QIcon
from PyQt6.QtWidgets import (QApplication, QVBoxLayout,
                             QLabel, QGridLayout,
                             QLineEdit, QPushButton, QMainWindow, QTableWidget, QTableWidgetItem, QDialog, QToolBar,
                             QComboBox, QStatusBar, QMessageBox)
import sys
import sqlite3


class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("School Management System")
        self.setMinimumSize(500, 400)

        file_menu_item = self.menuBar().addMenu("&File")
        help_menu_item = self.menuBar().addMenu("&Help")
        edit_menu_item = self.menuBar().addMenu("&Edit")

        add_student_action = QAction(QIcon("icons/add.png"), "Add Student", self)
        file_menu_item.addAction(add_student_action)
        add_student_action.triggered.connect(self.insert)

        about_action = QAction("About", self)
        help_menu_item.addAction(about_action)
        about_action.triggered.connect(self.about)

        search_action = QAction(QIcon("icons/search.png"), "Search", self)
        edit_menu_item.addAction(search_action)
        search_action.triggered.connect(self.search)

        self.table = QTableWidget()
        self.table.setColumnCount(4)
        self.table.setHorizontalHeaderLabels(("id", "name", "course", "mobile"))
        self.setCentralWidget(self.table)

        # Toolbar and Toolbar Elements

        toolbar = QToolBar()
        toolbar.setMovable(True)
        self.addToolBar(toolbar)

        toolbar.addAction(add_student_action)
        toolbar.addAction(search_action)

        # Status Bar

        self.statusbar = QStatusBar()
        self.setStatusBar(self.statusbar)

        # Detect Cell Click
        self.table.cellClicked.connect(self.cell_clicked)

    def cell_clicked(self):
        edit_button = QPushButton("Edit Record")
        edit_button.clicked.connect(self.edit)

        delete_button = QPushButton("Delete Record")
        delete_button.clicked.connect(self.delete)

        children = self.findChildren(QPushButton)
        if children:
            for child in children:
                self.statusbar.removeWidget(child)

        self.statusbar.addWidget(edit_button)
        self.statusbar.addWidget(delete_button)

    def load_Data(self):
        connection = sqlite3.connect("database.db")
        result = connection.execute("SELECT * FROM Students")
        self.table.setRowCount(0)
        for row_number, row_data in enumerate(result):
            self.table.insertRow(row_number)
            for column_number, data in enumerate(row_data):
                self.table.setItem(row_number, column_number, QTableWidgetItem(str(data)))
        connection.close()
        pass

    def insert(self):
        dialog = InsertDialog()
        dialog.exec()

    def search(self):
        dialog = SearchDialog()
        dialog.exec()

    def edit(self):
        dialog = EditDialog()
        dialog.exec()

    def delete(self):
        dialog = DeleteDialog()
        dialog.exec()

    def about(self):
        dialog = AboutDialog()
        dialog.exec()


class AboutDialog(QMessageBox):

    def __init__(self):
        super().__init__()
        self.setWindowTitle("About")
        content = """
        This app is a school management system where it keeps the records
        of students along with their course and mobile number.
        """
        self.setText(content)


class EditDialog(QDialog):

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

        self.setWindowTitle("Update Student")
        self.setFixedWidth(300)
        self.setFixedHeight(300)

        layout = QVBoxLayout()

        # Get student name from selected row
        index = main_window.table.currentRow()

        self.student_id = main_window.table.item(index, 0).text()

        student_name = main_window.table.item(index, 1).text()

        self.student_name = QLineEdit(student_name)
        self.student_name.setPlaceholderText("Name")
        layout.addWidget(self.student_name)

        course_name = main_window.table.item(index, 2).text()
        self.course_name = QComboBox()
        courses = ["Biology", "Math", "Physics", "Chemistry"]
        self.course_name.addItems(courses)
        self.course_name.setCurrentText(course_name)
        layout.addWidget(self.course_name)

        mobile = main_window.table.item(index, 3).text()
        self.mobile = QLineEdit(mobile)
        self.mobile.setPlaceholderText("Mobile")
        layout.addWidget(self.mobile)

        button = QPushButton("Update")
        button.clicked.connect(self.update_student)
        layout.addWidget(button)

        self.setLayout(layout)

    def update_student(self):
        connection = sqlite3.connect("database.db")
        cursor = connection.cursor()
        cursor.execute("UPDATE students SET name = ?, course = ?, mobile = ? WHERE id = ?", (
            self.student_name.text(), self.course_name.itemText(self.course_name.currentIndex()), self.mobile.text(),
            self.student_id))
        connection.commit()
        cursor.close()
        connection.close()
        main_window.load_Data()

        self.close()

        conformation_msg = QMessageBox()
        conformation_msg.setWindowTitle("Success")
        conformation_msg.setText("The student record was updated successfully")
        conformation_msg.exec()


class DeleteDialog(QDialog):

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

        self.setWindowTitle("Delete Student Record")

        layout = QGridLayout()
        conformation = QLabel("Are you sure ? Want to delete ?")
        yes = QPushButton("Yes")
        no = QPushButton("No")

        layout.addWidget(conformation, 0, 0, 1, 2)
        layout.addWidget(yes, 1, 0)
        layout.addWidget(no, 1, 1)

        self.setLayout(layout)

        yes.clicked.connect(self.delete_student)

    def delete_student(self):
        index = main_window.table.currentRow()
        student_id = main_window.table.item(index, 0).text()

        connection = sqlite3.connect("database.db")
        cursor = connection.cursor()
        cursor.execute("DELETE from students WHERE id = ?", (student_id,))
        connection.commit()
        cursor.close()
        connection.close()
        main_window.load_Data()

        self.close()

        conformation_msg = QMessageBox()
        conformation_msg.setWindowTitle("Success")
        conformation_msg.setText("The student record was deleted successfully")
        conformation_msg.exec()


class InsertDialog(QDialog):
    def __init__(self):
        super().__init__()

        self.setWindowTitle("Insert Student")
        self.setFixedWidth(300)
        self.setFixedHeight(300)

        layout = QVBoxLayout()

        self.student_name = QLineEdit()
        self.student_name.setPlaceholderText("Name")
        layout.addWidget(self.student_name)

        self.course_name = QComboBox()
        courses = ["Biology", "Math", "Physics", "Chemistry"]
        self.course_name.addItems(courses)
        layout.addWidget(self.course_name)

        self.mobile = QLineEdit()
        self.mobile.setPlaceholderText("Mobile")
        layout.addWidget(self.mobile)

        button = QPushButton("Register")
        button.clicked.connect(self.add_student)
        layout.addWidget(button)

        self.setLayout(layout)

    def add_student(self):
        name = self.student_name.text()
        course = self.course_name.itemText(self.course_name.currentIndex())
        mobile = self.mobile.text()
        connection = sqlite3.connect("database.db")
        cursor = connection.cursor()
        cursor.execute("INSERT INTO students (name, course, mobile) VALUES (?, ?, ?)", (name, course, mobile))
        connection.commit()
        cursor.close()
        connection.close()
        main_window.load_Data()

        self.close()

        conformation_msg = QMessageBox()
        conformation_msg.setWindowTitle("Success")
        conformation_msg.setText("The student record was added successfully")
        conformation_msg.exec()


class SearchDialog(QDialog):

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

        self.setWindowTitle("Search Student")
        self.setFixedWidth(300)
        self.setFixedHeight(300)

        layout = QVBoxLayout()
        self.student_name = QLineEdit()
        self.student_name.setPlaceholderText("Name")
        layout.addWidget(self.student_name)

        button = QPushButton("Search")
        button.clicked.connect(self.search)
        layout.addWidget(button)

        self.setLayout(layout)

    def search(self):
        name = self.student_name.text()
        connection = sqlite3.connect("database.db")
        cursor = connection.cursor()
        result = cursor.execute("SELECT * FROM students WHERE name = ?", (name,))
        rows = list(result)
        print(rows)
        items = main_window.table.findItems(name, Qt.MatchFlag.MatchFixedString)
        for item in items:
            print(item)
            main_window.table.item(item.row(), 1).setSelected(True)
        cursor.close()
        connection.close()


app = QApplication(sys.argv)
main_window = MainWindow()
main_window.show()
main_window.load_Data()
sys.exit(app.exec())