Twig is a template engine for PHP, which is the language used in Drupal. Twig can be used to design templates in generic PHP applications as well as Drupal themes.
Object-Oriented PHP
TopicObject-oriented PHP utilizes classes and objects to organize code into reusable chunks. This approach helps us organize complex applications, such as Drupal, into modular code called classes that can be reused across the entire system.
Configuration API in Drupal
CourseEntity API in Drupal
CourseOn occasion, you may need to modify the behavior of entity types defined by another module. Thankfully, Drupal includes several alter hooks that can be used to override the behavior of another entity.
In this tutorial, we will:
- Walk through the common Entity API hooks
- Look at example implementations of each
- And discuss the use cases for each
By the end of this tutorial, you will have a better understanding of how to override the default behavior of an entity type provided by Drupal core (or another contributed module) within your custom code.
The Typed Data API in Drupal helps add additional functionality to PHP's built-in data types, making working with data in Drupal much more predictable. It allows code to make intelligent guesses about the type of data that a field on an entity contains. For example, differentiating between a string of text and a string of text that represents a URL.
In this tutorial, we'll:
- Look at the 3 main types of typed data in Drupal: primitives, complex data, and lists.
- See how different data types and definitions are defined, and show how to define your own data type.
- Look at the interfaces provided by each data type to see some of the benefits of adding this abstraction layer.
By the end of this tutorial, you should have a better understanding of what the Typed Data API is, where you'll most likely encounter it, and how to use it in your code.
Entity CRUD (Create, Read, Update, and Delete) operations are handled via the EntityTypeManager service.
In this tutorial we'll:
- Learn how to use the
EntityTypeManagerservice to perform basic CRUD operations with examples you can copy/paste - Access both property and field values of an entity
- Update entities by setting new field values and then saving the object
By the end of this tutorial, you'll be able to understand Entity CRUD operations and be well on your way to becoming comfortable with accessing and manipulating entity values in code.
Field formatters are responsible for taking the data stored by a field and transforming it into what a visitor sees. We can define new field formatters to output data for new field types or to provide alternative formatting options for existing field types. Creating a field formatter plugin is a common task for Drupal developers.
In this tutorial we'll:
- Define a new background color field formatter that uses the string stored by our field_example_rgb field type as the background color of the output.
- Make it possible for site builders to toggle on or off a feature that automatically adjusts the foreground text color of the output.
By the end of this tutorial you should be able to define a new custom field formatter plugin with settings that a site administrator can configure.
Field API Overview
FreeIf you've ever created or edited a piece of content on a Drupal site you have already interacted with the Field API. The Field module (along with its user interface counterpart) is responsible for providing the forms and data components used to build up the content model that make up a Drupal site. Understanding how Drupal fields work and how they're constructed via the Field API is an important part of understanding how Drupal works.
In this tutorial, we're going to look at the main components that make up the Field API at a high level. We'll see how the Field UI module exposes the field types included in core. We'll also look at the three main pieces that compose fields: types, widgets and formatters.
Drupal's Field API specifies the implementation details for field types, widgets and formatters. It also provides several hooks that allow custom code to alter these implementation details. In this tutorial we'll take a look at these Field API hooks and see how they can be used to change field types, widgets and formatters.
By the end of this lesson, you should be able to:
- Identify existing Field API hooks for manipulating field behavior
- Understand the proper method for changing the behavior of a field type, widget or formatter
- Know where to find the documentation for these API functions, and how to find their implementations
Of the 3 main components of the field system -- types, widgets and formatters -- only 1 has an impact on the actual display of content for end users: field formatters. Field formatters are responsible for taking the data stored by a field and transforming it into the markup that is sent to the browser when an end user views your site.
In this tutorial we'll:
- Look at the role field formatters play in the Field API
- Identify the main components that make up a field formatter
By the end of this tutorial you should be able to define the role of a field formatter plugin.
Drupal's field system provides us with a flexible system of adding different types of discrete data to content types. This enables us to create rich content models. The Field API allows us to define these distinct field types by creating a new plugin. These plugins specify a FieldType attribute. In this tutorial, we'll look at these attributes in detail. We'll look at the implementations of field types from Drupal core. Also, we'll see what a new custom field type would look like.
By the end of this tutorial, you should be able to:
- Understand how field type definitions are created and exposed to Drupal
- Identify the various field types provided by Drupal core
- Understand the requirements for providing a specification for a new field type
Once we've explored the various field types provided by Drupal core, the next component of the Field API to explore is field widgets. Field widgets define how the data structure of the field is displayed on an edit form. When content editors interact with your field type they will be doing so via the field widget you provide. In this tutorial, we'll take a look at the field widgets provided by Drupal core, the plugin type required to define our own custom widget and how we can define multiple widget options for a single field type.
By the end of this tutorial, you should be able to:
- Understand where field widgets fit into the overall Field API
- Implement a custom field widget to support a particular field type
In their simplest form layout plugins in Drupal Layout Builder define the part of the content output that can't be changed. For example a three column layout will consist of three equal columns every time an editor decides to use it as the layout section. The editor can place whatever they want into the three columns. But they can not change the overall layout. This restricts editorial capabilities of using layout plugins since in real life a three column layout may need to consist of a wider middle column and narrower side columns, allow for column headings, or other customizations.
This flexibility is accomplished by creating, and exposing, configuration options for layout plugins in Drupal's Layout Builder. In more advanced cases, we can take this flexibility further by exposing an interface editors to dynamically define layout plugins.
In this tutorial we'll:
- Learn how to use custom PHP classes in the layout plugin annotation
- Learn what annotations properties can be used for custom layout declaration
- Define the concept of derivatives and outline scenarios for using them
- How to declare static single layouts using YAML format
By the end of this tutorial you'll learn advanced ways of declaring configurable custom layout plugins.
When building with Layout Builder, the list of blocks available for a site administrator to place in a layout can grow and become overwhelming to navigate. This is especially true when you've got a lot of different modules enabled, as each can add new blocks. As well, complex configurations may require site admins to create more and more custom blocks. Some blocks, like certain Views, or default core blocks like "Who's online", are not meant to be used within the Layout Builder. These blocks can clutter the UI and also impact the performance of Layout Builder UI. The contributed module Block List Override is designed to help solve this problem.
In this tutorial we'll:
- Learn what the Block List Override module does
- Install and configure the module to improve the user experience when creating layouts
By the end of this tutorial you should know how to use the Block List Override module to improve the UX of the Layout Builder interface.
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.
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.