The Views module is a query generator and render engine in Drupal core. It's typically used to create and output collections of items such as Drupal content entities. But it can also aggregate users, blocks, log records, and more. The output can be rendered many ways, including as a list, a grid, or an RSS feed. Views is commonly used in Drupal to create pages, blocks and other types of displays.

Through the Views API developers can expose new data to Views, add new configuration options, create new output plugins, field formatters, sort handlers, filter handlers, and more. By creating these customizations as extensions of Views instead of as stand alone queries, or hard-coded lists, you can empower site administrators to mix and match your customizations with the existing feature set in any way they might need.

In this tutorial we'll:

• Get a high level overview of the Views API.
• Discuss the functional parts of the Views API such as hooks, plugins, and data types.
• Learn how to use the Views API in your project.

By the end of this tutorial you'll have a solid understanding of the parts of the Views API and some guidance on which to use for your goals.

Layout plugins can be dynamically generated based on configuration using plugin derivatives. This allows developers to provide Drupal site administrators with a UI for creating new layout plugins, or to automatically register layout plugins based on the environment.

This is useful in situations where it's not enough to define a set of pre-configured layouts to use in the Layout Builder. Instead, you need to empower editors to declare their own new layout plugins without writing any code. Derivatives could also be used in scenarios where the layouts that should be made available depend on configuration set elsewhere in the module. Or, you might have a scenario where you want to have multiple different 2-column layouts, and for those layouts to have different names, so that they can be themed differently depending on which one is used.

In this tutorial we'll:

• Create a user interface that allows editors to dynamically define layouts via configuration.
• Learn how to set up a plugin deriver that creates layout plugins based on configuration.
• Create custom dynamic layout plugins with variable numbers of columns.

By the end of this tutorial you'll know how to declare dynamic custom layout plugins using derivatives.

Style plugins are responsible for determining how to output a set of rows. Individual rows are rendered by row plugins. Drupal core provides style plugins that include grid, HTML list, table, and unordered list styles. If you need to render the results in a different way, for example as tabs or accordions, or have special markup based on your project requirements, you may want to write a custom style plugin for Views. The advantage of this approach versus overriding the templates in a theme is that you may reuse this plugin in different views throughout the site, or even on different sites.

In this tutorial we'll:

• Learn how to create a custom Views style plugin and render output in the form of an accordion using the HTML5 <details> element.
• Demonstrate how to use a custom style plugin when building a view.

By the end of this tutorial you should know how to declare custom Views style plugins.

Drupal core comes with a few base themes: Stable, Stable 9, Classy, and Stark. Each one has a different intended use case. And all of them are useful as a reference for building your own themes.

In this tutorial we'll:

• Learn what each of the base themes included in Drupal core is intended to be used for
• Compare the output from the base themes with a focus on Stable and Classy

By the end of this tutorial you'll be able to explain the use case for each of the base themes included with Drupal core and make an informed decision about which, if any, to use when creating your own custom themes.

Themes and modules can alter the list of theme hook suggestions in order to add new ones, remove existing ones, or reorder the list. This powerful feature allows for the definition of custom logic in your application that can tell Drupal to use different templates based on your own unique needs. You might for example; use a different page template for authenticated users, or a custom block template for someone's birthday.

In this tutorial we'll cover:

• Adding new theme hook suggestions from a theme using hook_theme_suggestions_HOOK_alter()
• Altering the list of theme hook suggestions
• Removing theme hook suggestions
• Reordering the list of theme hook suggestions

In Drupal's Appearance UI, all themes get a theme settings form. As a theme developer, you can customize the theme settings form, enabling site administrators to have more control over the appearance of the theme.

In this tutorial, we'll show you how to add admin-configurable settings to your theme. In the process of doing this, we'll use a variety of theme and module development skills and assume you have some familiarity with using Drupal's Form API, Configuration API, and theme system (see Prerequisites).

By the end of this tutorial, you will be able to provide custom theme settings that an administrator can use to modify the appearance of the theme.

In this tutorial, we'll add and configure a contextual filter for a view. Our Baseball Awards content type has a field Year. We'll make it possible for a page to be dynamically created on our site that contains the year and lists the awards for that specific year. To do this, we'll add a contextual filter to the Baseball Awards view that will allow visitors to filter the list of awards by the award year. We'll also add a block using the summary view contextual filter configuration, which visitors can use to view results for specific years.

Drupal makes it easy to convert an array of strings to an ordered or unordered HTML list using '#theme' => 'item_list' elements in a render array. This is commonly done by module developers to display a list such as links to content, the values of settings in a module, or the names of everyone who has viewed a page. Displaying lists is a super common task for a content management system.

In this tutorial we'll look at:

• Outputting an array of items as an unordered <ul> list
• Properties specific to '#theme' => 'item_list' in a render array

By the end of this tutorial you should be able to output unordered lists.

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.

Modules can provide new render element types -- a powerful way to encapsulate complex logic into a reusable component. This can help to cut down on code repetition, and allow other module developers to build on your work. In this tutorial we'll:

• Define a recipe for creating a new render element type
• Look at the code for the marquee element type from the render_example module in the Examples for Developers project.

By the end of this tutorial you should be able to implement a new render element type in your own module and make use of it when defining content as part of a render array.