CODSOFT-TO-DO-LIST

🚀 Exciting News: Built My First To-Do List App in Python! I am thrilled to share a project I’ve been working on recently: a functional To-Do List Application built entirely using Python! 📝🐍 Author- Prem Somnath Sonawane https://ai.studio/apps/2d690c27-9353-45d6-8132-bf8bd64f7412?fullscreenApplet=true

Python To-Do Application Studio PEP 8 Gated Compare clean Object-Oriented Tkinter GUI & Functional Streamlined CLI with Sandbox Simulators Option 1: todo_cli.py """ Implementation 1: Command-Line Interface (CLI) To-Do List App Features persistent storage using 'todo_list.json' and handles basic error cases. Follows PEP 8 guidelines. """ import os import json

FILENAME = "todo_list.json"

def load_tasks(): """Loads tasks from a JSON file, returning a list of task dicts.""" if not os.path.exists(FILENAME): return [] try: with open(FILENAME, "r", encoding="utf-8") as file: return json.load(file) except (json.JSONDecodeError, IOError): print("Warning: Could not read 'todo_list.json'. Creating a new task list.") return []

def save_tasks(tasks): """Saves the current tasks list to a JSON file.""" try: with open(FILENAME, "w", encoding="utf-8") as file: json.dump(tasks, file, indent=4) except IOError: print("Error: Could not save tasks to file.")

def display_tasks(tasks): """Prints all active and completed tasks in a readable format.""" if not tasks: print("\nYour to-do list is empty.") return

print("\n--- Current To-Do List ---")
for idx, task in enumerate(tasks, start=1):
    status = "[✓] Completed" if task.get("completed") else "[✗] Pending"
    print(f"{idx}. {task['title']} - {status}")

def add_task(tasks): """Prompts the user to add a task, validating input.""" title = input("\nEnter the task description: ").strip() if not title: print("Error: Task description cannot be empty or just whitespace.") return

tasks.append({"title": title, "completed": False})
save_tasks(tasks)
print(f"Task '{title}' added successfully!")

def update_task(tasks): """Marks a task as completed.""" if not tasks: print("\nNo tasks available to update.") return

display_tasks(tasks)
try:
    choice = int(input("\nEnter the number of the task to mark as completed: "))
    if 1 <= choice <= len(tasks):
        tasks[choice - 1]["completed"] = True
        save_tasks(tasks)
        print(f"Task '{tasks[choice - 1]['title']}' marked as completed.")
    else:
        print("Error: Invalid task number.")
except ValueError:
    print("Error: Please enter a valid integer task number.")

def delete_task(tasks): """Deletes a selected task.""" if not tasks: print("\nNo tasks available to delete.") return

display_tasks(tasks)
try:
    choice = int(input("\nEnter the number of the task to delete: "))
    if 1 <= choice <= len(tasks):
        removed = tasks.pop(choice - 1)
        save_tasks(tasks)
        print(f"Task '{removed['title']}' deleted successfully.")
    else:
        print("Error: Invalid task number.")
except ValueError:
    print("Error: Please enter a valid integer task number.")

def main(): """Main terminal execution loop.""" tasks = load_tasks() while True: print("\n=========================") print(" Python To-Do CLI") print("=========================") print("1. View Tasks") print("2. Add Task") print("3. Update/Complete Task") print("4. Delete Task") print("5. Exit")

    choice = input("\nEnter your choice (1-5): ").strip()
    if choice == "1":
        display_tasks(tasks)
    elif choice == "2":
        add_task(tasks)
    elif choice == "3":
        update_task(tasks)
    elif choice == "4":
        delete_task(tasks)
    elif choice == "5":
        print("\nExiting To-Do App. Goodbye!")
        break
    else:
        print("Error: Invalid choice. Please choose a number from 1 to 5.")

if name == "main": main() OUTPUT: Python 3.11.4 (main, Jun 8 2026, 19:13:17) [GCC 11.3.0] on linux Type "help", "copyright", "credits" or "license" for more information.

python todo_cli.py ========================= Python To-Do CLI =========================

1. View Tasks

2. Add Task

3. Update/Complete Task

4. Delete Task

5. Exit Enter your choice (1-5): ========================= Python To-Do CLI =========================

6. View Tasks

7. Add Task

8. Update/Complete Task

9. Delete Task

10. Exit Enter your choice (1-5):

    Option 2: todo_gui.py """ Implementation 2: Graphical User Interface (GUI) To-Do List App Uses Python's native 'tkinter' library and native messagebox popups. Follows PEP 8 guidelines. """ import tkinter as tk from tkinter import messagebox import json import os

FILENAME = "todo_list.json"

class TodoGUIApp: def init(self, root): self.root = root self.root.title("Python To-Do List Application") self.root.geometry("480x520") self.root.minsize(400, 450) self.root.configure(bg="#f4f6fa")

    self.tasks = self.load_tasks()
    
    # UI Styling & Fonts
    self.title_font = ("Helvetica", 16, "bold")
    self.label_font = ("Helvetica", 10)
    self.btn_font = ("Helvetica", 10, "bold")
    
    self.create_widgets()
    self.populate_listbox()
    
def load_tasks(self):
    """Loads tasks from a JSON file, returning a list of task dicts."""
    if not os.path.exists(FILENAME):
        return []
    try:
        with open(FILENAME, "r", encoding="utf-8") as file:
            return json.load(file)
    except (json.JSONDecodeError, IOError):
        return []

def save_tasks(self):
    """Saves current state of tasks to 'todo_list.json'."""
    try:
        with open(FILENAME, "w", encoding="utf-8") as file:
            json.dump(self.tasks, file, indent=4)
    except IOError:
        messagebox.showerror("Error", "Could not save tasks to file.")

def create_widgets(self):
    """Builds all native tkinter components of the application."""
    # Top Title Frame
    title_frame = tk.Frame(self.root, bg="#f4f6fa", pady=10)
    title_frame.pack(fill=tk.X)
    
    title_label = tk.Label(
        title_frame, 
        text="★ To-Do Tasks Manager ★", 
        font=self.title_font, 
        bg="#f4f6fa", 
        fg="#2c3e50"
    )
    title_label.pack()

    # Input Frame (Entry + Button)
    input_frame = tk.Frame(self.root, bg="#f4f6fa", padx=15, pady=5)
    input_frame.pack(fill=tk.X)

    self.task_entry = tk.Entry(
        input_frame, 
        font=("Helvetica", 11), 
        bd=1, 
        relief=tk.SOLID
    )
    self.task_entry.pack(side=tk.LEFT, fill=tk.X, expand=True, ipady=4, padx=(0, 10))
    self.task_entry.bind("<Return>", lambda event: self.add_task())

    add_btn = tk.Button(
        input_frame, 
        text="Add Task", 
        font=self.btn_font, 
        bg="#3498db", 
        fg="white", 
        activebackground="#2980b9", 
        activeforeground="white", 
        relief=tk.FLAT, 
        padx=15, 
        pady=4,
        command=self.add_task
    )
    add_btn.pack(side=tk.RIGHT)

    # Central Listbox Frame with scrollbar
    list_frame = tk.Frame(self.root, bg="#f4f6fa", padx=15, pady=10)
    list_frame.pack(fill=tk.BOTH, expand=True)

    self.scrollbar = tk.Scrollbar(list_frame)
    self.scrollbar.pack(side=tk.RIGHT, fill=tk.Y)

    self.task_listbox = tk.Listbox(
        list_frame, 
        font=("Helvetica", 11), 
        bd=1, 
        relief=tk.SOLID, 
        selectbackground="#95a5a6", 
        selectforeground="white",
        yscrollcommand=self.scrollbar.set
    )
    self.task_listbox.pack(side=tk.LEFT, fill=tk.BOTH, expand=True)
    self.scrollbar.config(command=self.task_listbox.yview)

    # Buttons Control Frame
    ctrl_frame = tk.Frame(self.root, bg="#f4f6fa", padx=15, pady=15)
    ctrl_frame.pack(fill=tk.X)

    complete_btn = tk.Button(
        ctrl_frame, 
        text="Complete Task", 
        font=self.btn_font, 
        bg="#2ecc71", 
        fg="white", 
        activebackground="#27ae60", 
        activeforeground="white", 
        relief=tk.FLAT, 
        pady=8,
        command=self.complete_task
    )
    complete_btn.pack(side=tk.LEFT, fill=tk.X, expand=True, padx=(0, 10))

    delete_btn = tk.Button(
        ctrl_frame, 
        text="Delete Task", 
        font=self.btn_font, 
        bg="#e74c3c", 
        fg="white", 
        activebackground="#c0392b", 
        activeforeground="white", 
        relief=tk.FLAT, 
        pady=8,
        command=self.delete_task
    )
    delete_btn.pack(side=tk.RIGHT, fill=tk.X, expand=True)

def populate_listbox(self):
    """Clears and refills the Listbox with formatted task strings."""
    self.task_listbox.delete(0, tk.END)
    for task in self.tasks:
        # Change icon indicators to represent state
        status_indicator = "✔" if task.get("completed") else "✘"
        self.task_listbox.insert(tk.END, f" [{status_indicator}]  {task['title']}")

def add_task(self):
    """Add new task validation and storage."""
    title = self.task_entry.get().strip()
    if not title:
        # Trigger popup warnings for empty task
        messagebox.showwarning("Warning", "Cannot add an empty task. Please enter some text.")
        return

    self.tasks.append({"title": title, "completed": False})
    self.save_tasks()
    self.populate_listbox()
    self.task_entry.delete(0, tk.END)

def get_selected_index(self):
    """Helper to get and check selected task index. Raises warning message if none."""
    try:
        index = self.task_listbox.curselection()[0]
        return index
    except IndexError:
        # Prompt warning if button clicked without active selection
        messagebox.showwarning("Warning", "Please select a task from the listbox first.")
        return None

def complete_task(self):
    """Marks selected task as completed."""
    idx = self.get_selected_index()
    if idx is not None:
        self.tasks[idx]["completed"] = True
        self.save_tasks()
        self.populate_listbox()
        self.task_listbox.selection_set(idx)

def delete_task(self):
    """Deletes selected task."""
    idx = self.get_selected_index()
    if idx is not None:
        self.tasks.pop(idx)
        self.save_tasks()
        self.populate_listbox()

if name == "main": app_root = tk.Tk() app = TodoGUIApp(app_root) app_root.mainloop()