section_students.sort(key=lambda student: student.name)
        self.student_listbox.delete(0, tk.END)
        for student in section_students:
            student_name = student.name
            self.student_listbox.insert(tk.END, f"{student_name}")

    def add_attended_students(self):
        selected_students = self.student_listbox.curselection()
        for student_index in selected_students:
            student_info = self.student_listbox.get(student_index)
            self.attended_students_listbox.insert(tk.END, student_info)
        self.student_listbox.selection_clear(0, tk.END)

        remove_button = tk.Button(self.master, text="<== Remove", command=self.remove_attended_students)
        remove_button.grid(row=2, column=4, padx=5, pady=5)

    def remove_attended_students(self):
        selected_students = self.attended_students_listbox.curselection()
        for student_index in selected_students[::-1]:
            self.attended_students_listbox.delete(student_index)

    def on_section_change(self, event):
        self.attended_students_listbox.delete(0, tk.END)
        self.update_student_listbox()

    def add_attendance(self):
        student_id = self.student_id_var.get()
        student_name = self.student_name_var.get()
        student_department = self.student_department_var.get()
        if student_id and student_name and student_department:
            self.attended_students_listbox.insert(tk.END, f"{student_id} {student_name} {student_department}")
            self.student_id_var.set("")
            self.student_name_var.set("")
            self.student_department_var.set("")
        else:
            messagebox.showerror("Hata", "Lütfen öğrenci bilgilerini eksiksiz girin.")

    def export_attendance(self):
        section = self.section_var.get()
        week = self.week_var.get()
        filetype = self.filetype_var.get()
        filename = f"{section} {week}.{filetype}"
        file_path = filedialog.asksaveasfilename(defaultextension=filetype, initialfile=filename,
                                                 filetypes=[("Excel Dosyası", f"*.{filetype}")], parent=self.master)
        if file_path:
            if filetype == "xlsx":
                writer = pd.ExcelWriter(file_path)
                self.attended_students_listbox.insert(tk.END, "Attendance List Exported to Excel")
                self.attended_students_listbox.insert(tk.END, f"File saved as {filename}")
                df = pd.DataFrame(columns=["ID", "Name", "Department"])
                for i in range(self.attended_students_listbox.size()):
                    student_info = self.attended_students_listbox.get(i)
                    student_info_list = student_info.split(",")
                    student_id = student_info_list[0]
                    student_name = " ".join(student_info_list[1:-1])
                    student_department = student_info_list[-1]
                    df = df.append({"ID": student_id, "Name": student_name, "Department": student_department},
                                   ignore_index=True)
                df.to_excel(writer, index=False)
                writer.save()
            elif filetype == "csv":
                raise ValueError("Dosya türü desteklenmiyor")
            else:
                with open(file_path, "w") as f:
                    f.write("ID\tName\tDepartment\n")
                    for i in range(self.attended_students_listbox.size()):
                        student_info = self.attended_students_listbox.get(i)
                        student_info_list = student_info.split(",")
                        student_id = student_info_list[0]
                        student_name = " ".join(student_info_list[1:-1])
                        student_department = student_info_list[-1]
                        f.write(f"{student_id}\t{student_name}\t{student_department}\n")
                    self.attended_students_listbox.insert(tk.END, "Attendance List Exported to Text File")
                    self.attended_students_listbox.insert(tk.END, f"File saved as {filename}")


root = tk.Tk()
app = AttendanceApp(root)
app.master.geometry("600x300")
app.master.resizable(False, False)
root.mainloop()