Why forms drive user interaction in Ruby on Rails - See It in Action

Why forms drive user interaction

📖 Scenario: You are building a simple web page where users can submit their favorite color. This form will collect the user's input and display it back to them. Forms are important because they let users tell the website what they want or like.

🎯 Goal: Create a basic Rails form that asks the user for their favorite color and then shows that color on the page after submission.

📋 What You'll Learn

Create a controller with an action to show the form

Add a form in the view that submits the favorite color

Create a controller action to receive the form data

Display the submitted favorite color back to the user

💡 Why This Matters

🌍 Real World

Forms are everywhere on the web. They let users sign up, log in, send messages, and share preferences.

💼 Career

Understanding forms and user input handling is essential for web developers building interactive websites and apps.

1

Set up the controller and initial action

Create a controller named ColorsController with an action called new that will show the form to the user.

Ruby on Rails

# Your code here to create ColorsController with new action

Need a hint?

Use rails generate controller Colors new or write the controller manually with a new method.

2

Add a form to collect favorite color

In the new.html.erb view file, add a form using form_with that has a text field named favorite_color and a submit button.

Ruby on Rails

class ColorsController 

Need a hint?

Use form_with with url: '/colors/create' and method: :post. Use text_field_tag :favorite_color for the input.

3

Create the action to receive form data

Add a create action in ColorsController that reads the favorite_color from params and stores it in an instance variable @color.

Ruby on Rails

class ColorsController < ApplicationController
  def new
  end

  # Add create action below
  # Your code here
end

Need a hint?

Use params[:favorite_color] to get the submitted value and save it in @color.

4

Display the submitted favorite color

Create a view file create.html.erb that shows the text: Your favorite color is: followed by the value of @color.

Ruby on Rails

class ColorsController 
# Your code here

Need a hint?

Use ERB tags <%= @color %> inside a paragraph to show the color.