Data Processing

To create a student calling application, we need to extract student names and IDs from an Excel speradsheet. This example uses the pandas library to read data.

pip install pandas
pip install openpyxl

The input Excel file (demo.xlsx) contains columns such as "ID" and "Name". We load and validate the data:

import pandas as pd

def process_student_data(file_path):
    df = pd.read_excel(file_path)
    columns = df.columns.tolist()
    assert "ID" in columns, "Column named 'ID' is required!"
    assert "Name" in columns, "Column named 'Name' is required!"
    return [f"{row['ID']} {row['Name']}" for _, row in df.iterrows()]

GUI Construction

Using tkinter, we construct a graphical interface for the application.

import tkinter as tk
import random

running = False

class CallRollApp(tk.Tk):
    def __init__(self, student_list):
        super().__init__()
        self.student_list = student_list
        self.running = False
        self.title("Student Selector")
        self.geometry("400x300")
        
        self.display_var = tk.StringVar(value="Ready to start")
        self.display_label = tk.Label(self, textvariable=self.display_var)
        self.display_label.pack(pady=20)
        
        self.start_button = tk.Button(self, text="Start", command=self.start_selection)
        self.start_button.pack(pady=10)
        
        self.stop_button = tk.Button(self, text="Stop", command=self.stop_selection)
        self.stop_button.pack(pady=10)

    def roll_selection(self):
        self.display_var.set(random.choice(self.student_list))
        if self.running:
            self.after(50, self.roll_selection)

    def start_selection(self):
        if not self.running:
            self.running = True
            self.roll_selection()

    def stop_selection(self):
        self.running = False

Enhanced Featurse

To improve usability, we allow dynamic file selection via a file dialog.

from tkinter import filedialog


class FileUploadWindow(tk.Tk):
    def __init__(self):
        super().__init__()
        self.title("Upload Students File")
        self.geometry("350x100")
        
        tk.Label(self, text="File Path").grid(row=0, column=0, padx=(10, 0), pady=10)
        self.file_entry = tk.Entry(self)
        self.file_entry.grid(row=0, column=1, columnspan=2, padx=(0, 10), ipadx=60)
        
        tk.Button(self, text="Browse", command=self.browse_file).grid(row=2, column=1, pady=10)
        tk.Button(self, text="Load Data", command=self.load_data).grid(row=2, column=2, padx=(0, 10))

    def browse_file(self):
        file_path = filedialog.askopenfilename(
            title="Select Excel File",
            filetypes=[("Excel files", "*.xlsx *.xls")]
        )
        self.file_entry.delete(0, tk.END)
        self.file_entry.insert(0, file_path)

    def load_data(self):
        try:
            data = process_student_data(self.file_entry.get())
            self.destroy()
            CallRollApp(data).mainloop()
        except Exception as e:
            from tkinter.messagebox import showwarning
            showwarning("Error", f"Failed to load data:\n{e}")

Execution Flow

The application starts by launching the file upload window. After selecting and loading the Excel file, it transitions to the student selection interface where users can start and stop the random selection process.