Welcome back! So far, we've learned how to retrieve ToDo items using GET queries. Now, it's time to make our application more interactive by allowing users to create new ToDo items. This lesson will focus on setting up the creation queries and building a form for users to input their ToDo items.

Creating ToDo items is a fundamental feature for our application. Imagine an app where you can see tasks but can't add new ones — it wouldn't be very useful! By the end of this lesson, you'll have significantly enhanced your app's functionality by enabling users to add new tasks.

In this lesson, we will cover the following key concepts:

1. Creating a form for adding new ToDo items.
2. Handling form submissions to save the new ToDo items.
3. Redirecting users to the details page of the newly created ToDo.

Let's start with setting up the controller. Open your todos_controller.rb and update it as follows:

Code Explanation

• new Action: This method initializes a new @todo object with default values (id, title, and description set to nil or empty strings). This is necessary to instantiate the form fields when creating a new ToDo item.

• create Action: This method is responsible for handling the submission of the new form. It calls a service (TodoService.create) that processes todo_params to create a new ToDo item. After successfully creating a new item, it redirects the user to the details page of the new ToDo by using .

To support the creation of new ToDo items, we'll simulate storage using an in-memory list. Below is the modified TodoService code:

Code Explanation

• In-Memory List: We're using an instance variable @todos to store ToDo items in memory. This approach allows us to manage ToDo items during the runtime of the application.

• create Method: This method initializes @todos as an empty array if it's not already. It generates a unique ID for the new ToDo based on the previous item's ID, constructs the todo item with the provided parameters, and appends it to @todos.

• get_all Method: This method returns all stored ToDo items from the in-memory list.

Next, we will set up the form view in app/views/todos/new.html.erb to collect user input.

Code Explanation

• form_with Method: This helper builds a form scoped to :todo. It sets the form’s submission URL to todos_path, ensuring the data is sent to the create action of TodosController. The local: true option makes sure that the form submits the data using a regular HTTP request, not AJAX.

• form.label and Field Methods: These are used to generate input elements for title and description. form.label generates a label tag for each field, while form.text_field and form.text_area create the input boxes for users to type in the title and description, respectively.

Creating new ToDo items is a critical feature for any task management application. It empowers users to manage their tasks dynamically, making the app far more useful. By understanding how to create new entries, you're adding a layer of functionality that is essential for interactive applications.

When users can easily add new tasks, your application becomes more than just a static list of predefined items. It becomes a tool that adapts to the users' needs. This capability boosts user engagement and makes your app practical for real-world use.

With excitement in the air, let's dive into the practice section and see this feature come to life!