Building a Simple To-Do List Application in Ruby 

1. Project Setup:

Start by creating a new directory for your project and navigate into it:

mkdir todo_app
cd todo_app

2. Create the Main Ruby File

Inside your project directory, create a file named todo.rb and open it in your text editor.

3. Implement the To-Do Class

In todo.rb, define a Todo class to represent a single to-do item. Each to-do item will have a description and a status (complete or incomplete). Here’s a basic implementation:

class Todo
  attr_accessor :description, :complete

  def initialize(description)
    @description = description
    @complete = false
  end

  def to_s
    "[#{complete ? 'X' : ' '}] #{description}"
  end
end

This class has a constructor to initialize a to-do item and a to_s method to provide a string representation of the to-do item.

4. Create the To-Do List Class

Next, create a TodoList class to manage a list of to-do items. Add methods to add, remove, and display to-do items:

class TodoList
  attr_accessor :todos

  def initialize
    @todos = []
  end

  def add_todo(description)
    todo = Todo.new(description)
    todos << todo
  end

  def remove_todo(index)
    todos.delete_at(index)
  end

  def display_todos
    puts "To-Do List:"
    todos.each_with_index { |todo, index| puts "#{index + 1}. #{todo}" }
  end
end

5. Implement User Interface

In the same todo.rb file, add a simple user interface to interact with the to-do list:

todo_list = TodoList.new

loop do
  puts "\n1. Add Todo"
  puts "2. Remove Todo"
  puts "3. Display Todos"
  puts "4. Quit"
  print "Choose an option: "

  choice = gets.chomp.to_i

  case choice
  when 1
    print "Enter todo description: "
    description = gets.chomp
    todo_list.add_todo(description)
    puts "Todo added!"
  when 2
    print "Enter the todo number to remove: "
    index = gets.chomp.to_i - 1
    todo_list.remove_todo(index)
    puts "Todo removed!"
  when 3
    todo_list.display_todos
  when 4
    puts "Goodbye!"
    break
  else
    puts "Invalid option. Please choose again."
  end
end

6. Run Your To-Do List App

Save your changes and run your Ruby application:

 ruby todo.rb

You should see a menu prompting you to add, remove, display, or quit. Follow the prompts to interact with your to-do list.

Conclusion

Congratulations! You’ve just built a simple To-Do List application in Ruby. This project covers fundamental concepts such as class creation, user input handling, and basic data structures. As you continue to enhance your Ruby skills, consider exploring more advanced features, such as file I/O, error handling, and testing.

Remember that this is a starting point, and you can extend and modify the application based on your preferences and requirements. Happy coding!