Views has always been a staple module for any Drupal site. It was so popular and needed that it ended up being incorporated into Drupal 8 core. So now, each new Drupal site ships with Views out of the box, fully integrated with the rest of the system and powering a great number of core features.

Essentially, Views is a tool for creating and displaying lists of data. This data can be almost anything, but we mostly use Drupal entities as they are now so robust. It provides the architecture to build and manipulate complex queries through the UI as well as many different ways of outputting the resulting data. From a module developer's point of View (yes, pun intended), much of this power has been broken down into multiple layers of building blocks, abstracted as plugins. Moreover, in keeping with tradition, there are also a multitude of hooks that are fired at different stages, with which we can programmatically contribute to or influence Views.

In this chapter, we will look at the Views ecosystem from a module developer's perspective. As such, we won't be spending that much time with its site-building capabilities as one can easily argue an entire book could be dedicated just to that. Instead, we will focus on what we as module developers can do to empower site builders to have even more capabilities at their finger-tips, as well as manipulating Views to behave the way our functionality needs them to.

So, what will we actually do in this chapter? We will first start with integrating our Product entity type with Views. The entity system and Views can work very closely together, and all we need to do is point them to one another. Then, we will switch gears and expose our own custom player and team data (from Chapter 8 , The Database API) to Views so our site builders can build Views that list this information, complete with filters, sorts, arguments, and the whole shebang. From there, we will look at how we can also alter data that has been exposed to Views by other modules, like entity data such as Nodes.

Next, you will learn how to create your own ViewsField, ViewsFilter, and ViewsArgument plugins to account for those occasional requirements for which the existing ones are a bit lacking. Finally, we will talk a little bit about theming Views and the main components that play a role in this, just to get you going in the right direction, and applying the lessons from Chapter 4, Theming.

By the end of this chapter, you will get a pretty good understanding of how to leverage Views on top of your own data, as well as modifying or contributing to how other modules leverage it. You should also get a pretty good understanding of the Views plugin ecosystem, even if quite a bit of work will have to be done on your own, studying the available plugins of all types.

So, let's get to it.