Chapter 8: Use Ref to Hide Stuff

In the previous chapter, we learned how the React context is designed and how to use a useContext hook to make an update for an area. In this chapter, we will introduce another React entity, a ref. We will learn how to access a DOM element via a ref and walk through the design and source code behind the useRef hook. We will also describe how to work with a persistent value without dispatching an update. In the end, we'll apply refs to a couple of practical problems, such as clicking outside of the menu, avoiding memory leaks, setting up a mule, and locating the current value. And we'll also reveal two bonus topics in the Appendix section, the callback ref and forward ref.

We will cover the following topics in this chapter:

• Accessing DOM elements
• Understanding useRef design
• State without an update
• Test driving useRef
• useRef examples
• Questions and answers
• Appendix