In this exercise, we'll practice theming by overriding the main menu template. We'll:

• Override and rename the main menu template so that it will only affect the main menu component of our Drupal site.
• Add Bootstrap classes from the base nav component into our overridden main menu template file.
• Add CSS classes to HTML selectors using attributes.addClass() and set methods.

We recommend that you work on the exercise steps below first. You can refer to the video if you need some help.

In this exercise, we'll continue our template overriding practice by overriding the image field template. We'll consult the Bootstrap documentation and add a responsive image class that will apply to any images uploaded by a user to the field_image field. Once again, we'll add this class to the classes array in the set Twig tag. You should work on the exercise steps below first, and you can refer to the video if you need some help.

In this exercise, we'll practice using the t filter in a Twig template. As a best practice, all hard-coded text in a template should be translatable. Simple text (containing no dynamic tokens) can be passed through the t filter to achieve this objective. Along the way, we'll also use a basic conditional if statement with Twig. We recommend that you try following the exercise's steps first, and refer to the video if you need help.

Preprocess functions allow you to change existing variables, or add new variables, for a template file using PHP code. In this exercise, you'll:

• Define a PHP function that implements a preprocess hook
• Create a new variable named {{ today }} that contains the current date and gets passed to the page.html.twig template file.

We recommend that you try the exercise's steps first, and refer to the video if you need help.

When defining new layout plugins for Drupal you can add custom CSS and JavaScript via asset libraries. This allows for the creation of layouts with complex structures and interactive elements. Those elements might include grids, tabs, and accordions. Drupal allows you to attach custom CSS and JavaScript directly to a layout plugin, or via the layout's Twig template file.

In this tutorial we'll:

• Define a custom asset library with JavaScript and CSS functionality
• Attach the asset library to the custom layout plugin
• Transform a multicolumn layout into tabs

By the end of this tutorial you should know how to attach custom CSS and JavaScript to a layout plugin to add interactivity and styling.

The Layout Builder Styles module extends the Drupal core Layout Builder UI to add the ability for editors to apply custom CSS classes to the blocks and sections that make up a layout. This gives layout editors more control over the look and feel of elements within a layout. It's especially useful when using Drupal's Layout Builder in conjunction with a design system like Bootstrap, Material UI, or your own predefined utility classes.

The module allows site builders to define new styles. Then, when placing a block into a layout, if there are any styles available for the block type, the user is presented with a select list where they can choose one or more to apply. When a style is applied, any CSS classes associated with the style are added to the markup. Also, a new style-specific theme hook suggestion is added to the block to allow for further customization.

In this tutorial we'll:

• Install and configure the Drupal Layout Builder Styles module
• Learn how to define new styles
• Learn how anyone editing a layout can apply the styles we defined to a block or section in the layout to change the UX

By the end of this tutorial, you should be able to use the Layout Builder Styles module to allow editors to add predefined styles to existing layouts and blocks without writing any code.

Access control for the Media entities in Drupal works in much the same way as any other content entity. The module provides fine-grained control over create, update, and delete operations, while providing only basic control over who can view Media assets. The thinking is that there are too many possible permutations of how an application may want to restrict read access to content. Therefore, rather than try and pick one setting and add it to core, it's left entirely up to the site administrator and contributed modules.

In this tutorial we'll:

• Look at the different permissions provided by the Media module for controlling access to Media entity operations
• Discuss some common misconceptions about file permissions that can lead to potentially exposing private data

By the end of this tutorial you should know how to configure access control for Media entities, and explain how access control relates to files attached to a Media entity attached to a Node.

Drupal media entities are fieldable entities, which means that you can add any custom fields you want to your Media types. These fields can be used for collecting additional metadata about a resource, categorizing and organizing resources so they're easier to find in a large media library, or for displaying information like a photo credit or transcript for a video. The possibilities are endless once you know how to add, and optionally display, fields in Drupal.

Some example use cases for adding fields to Media types:

• Collect, and display, a credit to go along with a photo. This could also be a date, a location, or any other metadata.
• Store resource width and height dimensions as custom fields so they can be referenced by display logic in the theme layer.
• Use Taxonomy reference fields to add tags or categories to help keep a large library organized.

In this tutorial we'll:

• Learn how to add fields to a Media type
• Verify our new custom field is working

By the end of this tutorial you'll know how to add custom fields to any Media type.

The most common way to use Drupal's Media items is to add fields to content types, allowing the Media entities to be associated with one or more pieces of content. For example, adding a cover image to an article, or embedding a set of YouTube videos into a tutorial. This is accomplished by adding a Media field to the content type in question.

In this tutorial we'll:

• Explain what the different Media field-specific configuration options do
• Add a Media field to the existing Article content type
• Explain what the different field-specific configuration options do
• Confirm that it worked by verifying that the form for adding an article has the new field

By the end of this tutorial you'll know how to add a Media field to any content type, or any other fieldable entity, in order to allow Media items to be associated with the content.

Media entities in Drupal are content entities, and can be administered like most other Drupal content entities. In most cases you'll likely add new Media entities via the Media Library widget when creating a new content entity like an Article. However, it's possible to add them to the library without having to attach them to a piece of content. You may also want to update an existing Media entity, or just search the library to see whether something already exists.

In this tutorial we'll:

• Learn what a Media entity is in Drupal
• Get an overview of the main Media management page
• Learn how to add, edit, and delete, Media entities
• Learn how to bulk edit Media entities in Drupal

By the end of this tutorial you'll know how to perform basic find, add, edit, and delete operations to manage the Media entities in your library.

When using the Drupal Media Library to browse for available Media entities to attach to your content, the interface that you see inside the modal window is created using Views. This means you can change it for your specific use-case. This is most useful when you want to expose filters for custom fields to allow users to more easily locate content in your library. As your library of media grows, you can create powerful application-specific ways for content authors to segment the list and find their assets.

In this tutorial we'll:

• Learn how to edit the Views used by the Drupal Media Library browser
• Add a new exposed filter for the custom tags field on some media entities
• Demonstrate how this change affects the user interface for locating and selecting media

By the end of this tutorial you should be able to customize the View used by the Media Library to add new filters and make other use-case specific changes.

Media Source plugins in Drupal have a powerful feature, called field mapping, that allows an administrator to configure a Media entity type to automatically populate the value of custom fields based on metadata retrieved from the source content. For example, you can add a creator field to the Remote Video Media type, which can use YouTube as a source. When a content author adds a new Remote Video entity they can provide a URL for the YouTube video. Then the source plugin can extract the creator's name from the YouTube API and use that data to populate a custom field. This saves the content author from having to do that work themselves.

In this tutorial we'll learn:

• How to discover what source metadata is available
• How to configure a Drupal Media type to automatically populate custom fields

By the end of this tutorial you should be able to add a custom field to a Media type on your Drupal site and automatically populate it with data retrieved from the source content.

One of the most powerful features of Drupal's Media Library is that it enables content authors to re-use media entities. Have a favorite image that you like to use with all blog posts about a specific topic? Or a default icon you want to use for a tutorial unless an alternative is provided? The Media Library can accommodate this without requiring you to keep a copy of the image locally and then attach it to every node where it's needed.

This can lead to a potential issue when an editor deletes an image, thinking they've also deleted all the content that used it. If they missed a post referencing the now deleted image, what happens when there is no image to show?

The contributed Entity Usage module provides a mechanism for tracking relationships between entities. This is essential functionality when working with a library of reusable media entities because it helps ensure that media entities attached to content are not deleted.

In this tutorial we'll:

• Discuss the use case for the Entity Usage module
• Learn how to configure Entity Usage to keep track of relationships between media entities and nodes that reference them
• Prevent media items from being deleted if they are in use somewhere on the site

By the end of this tutorial you should be able to explain what the Entity Usage module does, and how to use it to solve common problems related to deleting items from a large Media library.

A commonly asked question is, "How do you add images to the body of a content item in Drupal?" You can allow users to embed images, videos, or any other media into a field configured with a WYSIWYG editor, such as CKEditor. In this tutorial, we’ll show you how to enable Drupal’s Insert Media button for CKEditor, and configure the corresponding text format so that it can render embedded Media entities.

Content authors can then use the Media Library to select images (or other media) to embed into the page.

In this tutorial we'll:

• Learn how to enable the Insert Media button for CKEditor
• Demonstrate how to insert media into the body of a content item (or any other field configured to use CKEditor)

By the end of this tutorial you should know how to configure Drupal to allow content authors to embed images in content items.

Drupal's media management tools, the Media and Media Library modules, provide content authors with drag-and-drop media and asset handling, full WYSIWYG editor integration, and a library of reusable media assets. There's minimal configuration required to get started, but full control via Drupal's standard Entity and Field systems for those who need it.

In this tutorial we'll:

• Provide an introduction to the media system in Drupal and its use-cases
• Explain the Drupal core features that the Media system is built on
• Link to other tutorials that will go into much more depth on these topics

By the end of this tutorial you should know what role the Media and Media Library core modules fill and know whether or not you'll want to make use of them on your project.

Media entities are standard Drupal fieldable content entities. For the most part, they function, and are managed, in the same way as Nodes. So if you've previously created content in Drupal, much of working with Media entities should be familiar -- with some notable exceptions related to the connections between Media types and the media resources they represent.

In this tutorial we'll:

• Get an overview of Media entities, Media types, and Media fields in Drupal
• Point to other tutorials that go into more depth on individual topics
• Learn some basic terminology and concepts related to the Media system in Drupal

By the end of this tutorial you'll have an overview of the pieces that make up the Media system in Drupal core.

The Drupal core Media Library module provides an enhanced user interface for locating Media entities and attaching them to an article. It's a drop-in replacement for the default entity reference widget which uses a not very intuitive autocomplete field. Using the Drupal core Media Library module requires minimal configuration.

If you want to provide content creators with a gallery-like library of Media entities that they can browse through in order to find the ones they want to add to their content, the Media Library is the easiest way to do it. It can be configured to work with both Media fields and the CKEditor powered WYSIWYG editor commonly used for editing the body field of Drupal nodes. There's really no reason not to use it.

In addition to providing a better UI for locating existing Media entities, the Media Library provides a way to create new Media entities right from the content creation form. This prevents an otherwise confusing requirement where Media entities need to be created, via a different set of forms, before they can be used.

In this tutorial we'll:

• Install and configure the Media Library module to work with Media fields
• Use the user interface provided by the Media Library to improve the experience of finding and selecting Media entities to associate with a piece of content

By the end of this tutorial you'll know how to replace the default entity reference widget used for selecting Media entities with the much improved Media Library UI.

Media entities, like any content entity, work great with all the different features Drupal provides for changing the way things are displayed: view modes, Layout Builder, theme templates, and more. We're big fans of using view modes to create a component-like design system where entity types have view modes representing the different context in which they're displayed. Then we theme the view modes. This works great for displaying Media entities associated with a page and for changing the way that Media assets are displayed within the Media Library browser.

In this tutorial we'll:

• Create Hero and Sidebar view modes for Media entities
• Configure the Image Media type to use the new view modes and style each one differently
• Use the new view modes to render Image Media assets within a Layout
• Update the Media library view mode that's used by the Media Library browser to display additional information alongside the thumbnails used when selecting Media to attach to a page

By the end of this tutorial you should be able to change the way that Media assets are displayed by using view modes and display formatters in a Drupal site.

The Render API consists of two parts: structured arrays that provide data and hints about how that data should be rendered, and a rendering pipeline that can be used to render these arrays into various output formats. Understanding at least the basics of how the Render API works, the difference between elements and properties, and the concept of callback functions is an integral part of learning Drupal.

In this tutorial we'll:

• Look at the fundamentals of the Drupal Render API
• Point to additional material to provide more detail about the inner workings of the Render API and how content is output in Drupal