import os

class TaskTracker:

def __init__(self):

self.tasks = []

# Function to display the menu

def display_menu(self):

print("\nTo-Do List Application")

print("1. Add a new task")

print("2. View all tasks")

print("3. Mark a task as completed")

print("4. Delete a task")

print("5. Save tasks to file")

print("6. Load tasks from file")

print("7. Exit")

# Function to get user choice

def get_choice(self):

return input("\n\nEnter your choice: ")

def back_to_menu(self):

return input("\n\nPress [Enter] to return")

# Function to add a new task

def add_task(self):

task = input("Enter the new task: ")

self.tasks.append({"task": task, "completed": False})

print(f"Task '{task}' added.")

# Function to view all tasks

def view_tasks(self):

if not self.tasks:

print("No tasks available.")

return

for i, task in enumerate(self.tasks, 1):

status = "Completed" if task["completed"] else "Pending"

print(f"{i}. {task['task']} - {status}")

# Function to mark a task as completed

def mark_task_completed(self):

self.view_tasks()

task_num = int(input("Enter the task number to mark as completed: "))

if 0 < task_num <= len(self.tasks):

self.tasks[task_num - 1]["completed"] = True

print(f"Task '{self.tasks[task_num - 1]['task']}' marked as completed.")

else:

print("Invalid task number.")

# Function to delete a task

def delete_task(self):

self.view_tasks()

task_num = int(input("Enter the task number to delete: "))

if 0 < task_num <= len(self.tasks):

task = self.tasks.pop(task_num - 1)

print(f"Task '{task['task']}' deleted.")

else:

print("Invalid task number.")

# Function to save tasks to a file

def save_tasks_to_file(self):

with open("tasks.txt", "w") as file:

for task in self.tasks:

file.write(f"{task['task']}|{task['completed']}\n")

print("Tasks saved to file.")

# Function to load tasks from a file

def load_tasks_from_file(self):

self.tasks = []

if os.path.exists("tasks.txt"):

with open("tasks.txt", "r") as file:

for line in file:

task, completed = line.strip().split("|")

self.tasks.append({"task": task, "completed": completed == "True"})

print("Tasks loaded from file.")

else:

print("No saved tasks found.")

return self.tasks

def clear_screen(self):

os.system('cls' if os.name == 'nt' else 'clear')