Layouts and Partials

7 Months ago | 42 views

**Course Title:** Ruby Programming: From Basics to Advanced Techniques **Section Title:** Advanced Rails: Routing and Views **Topic:** Layouts and partials for better code organization **Introduction** In the previous topic, we explored how to create and use views with ERB and HAML. However, as our Rails applications grow in complexity, we need to find ways to organize our code better. This is where layouts and partials come in – two powerful tools that help us reuse code and make our views more maintainable. In this topic, we'll delve into the world of layouts and partials, and learn how to use them to improve our code organization. **What are Layouts?** A layout is a template that surrounds the content of a view, providing a consistent look and feel across multiple pages. Layouts are typically used to define the overall structure of a page, including the HTML header, footer, and navigation menu. In Rails, layouts are stored in the `app/views/layouts` directory. **Creating a Layout** To create a layout, simply create a new file in the `app/views/layouts` directory. For example, let's create a layout called `application.html.erb`: ```erb  <!DOCTYPE html> <html> <head> <titleRuby Programming: From Basics to Advanced Techniques</title> </head> <body> <%= yield %> </body> </html> ``` In this example, the `yield` keyword is used to indicate where the content of the view should be rendered. **Using a Layout** To use a layout, you simply need to specify it in your controller. For example: ```ruby # app/controllers/examples_controller.rb class ExamplesController < ApplicationController layout 'application' end ``` In this example, the `ExamplesController` will use the `application` layout for all its actions. **What are Partials?** A partial is a reusable piece of code that can be used across multiple views. Partials are typically used to render small bits of code, such as navigation menus or form fields. In Rails, partials are stored in the `app/views` directory, and are prefixed with an underscore. **Creating a Partial** To create a partial, simply create a new file in the `app/views` directory, prefixed with an underscore. For example, let's create a partial called `_navigation.html.erb`: ```erb  <ul> <li><%= link_to 'Home', root_path %></li> <li><%= link_to 'About', about_path %></li> </ul> ``` In this example, the partial renders an unordered list with links to the home and about pages. **Using a Partial** To use a partial, you simply need to render it in your view using the `render` method. For example: ```erb  <h1>Examples</h1> <%= render partial: 'navigation' %> <p>This is the examples page.</p> ``` In this example, the `_navigation.html.erb` partial is rendered below the header. **Key Concepts** * Layouts are templates that surround the content of a view, providing a consistent look and feel across multiple pages. * Partials are reusable pieces of code that can be used across multiple views. * Layouts and partials help improve code organization by allowing us to reuse code and reduce duplication. **Practical Takeaways** * Use layouts to define the overall structure of a page. * Use partials to render small bits of code, such as navigation menus or form fields. * Store layouts in the `app/views/layouts` directory. * Store partials in the `app/views` directory, prefixed with an underscore. **External Resources** * [Rails Guides: Layouts and Rendering](https://guides.rubyonrails.org/layouts_and_rendering.html) * [Rails API: ActionView::Layouts](https://api.rubyonrails.org/classes/ActionView/Layouts.html) **Leave a Comment or Ask for Help** If you have any questions or need help with layouts and partials, please leave a comment below. We'll do our best to help you out. **What's Next?** In the next topic, we'll explore how to handle form submissions and validations in Rails. We'll learn how to create forms, validate user input, and handle errors. Stay tuned! **Handling form submissions and validations**

Course

Layouts and Partials

Images