Hook Function

[00:00] Okay, so we want to have a useSearchParams hook. We'll make it right here, useSearchParams, and we're going to take everything that has to do with the search params. So we've got our state right here, our initializer, lazy initializer. We've got our useEffect and our setSearchParams. All of that stuff is going to come up here into useSearchParams and then we'll

[00:19] return the search params and setSearchParams. We're going to add this as const to the end of it, and that's going to change the type information. So if I don't have the as const, then the return type of this is going to be an array of, let's see, where does the return type start?

[00:38] It's basically, it sees it as an array of search params or a setSearchParams function, whereas this, by adding as const, it says, oh, okay, so this is literally an array that has the first item being the search params and the second item being a function that allows you to set the search params.

[00:57] So it's not an array of any number of items that's one or the other. It's literally a read-only array of two items. The first is this, the second is that. So that as const is definitely needed on hooks like this. Okay, great. So with useSearchParams implemented now,

[01:13] we can grab our search params and setSearchParams from useSearchParams. And like I said, not a lot of lines of code changed. If you look at the diff, there's really not a whole lot there. And it does still work. So this is functioning the way that it should. We're in a good place.

[01:33] We can initialize in the right place and everything is working just fine. We literally just moved all of the code from the app into useSearchParams. And what's cool, what I think is cool about this is this is just like normal JavaScript stuff here. There's nothing really React specific that we did here.

[01:53] We're just refactoring, moving some code. Now, it does come with some funniness of when you're starting to think about, oh, I wanna make this more generic and make it work in more places, which we're gonna talk about next. But the value of it being just JavaScript,

[02:11] I think is a really beneficial aspect of the way that hooks work. So, all right, well done.

[00:00] So, your job is to make a reusable useSearchParams hook so that we can have the search params and setSearchParams. There's going to be a problem with what things look like when you're done. It actually is going to be pretty quick. There's not a whole lot of lines of code you need to change.

[00:18] But it's not going to be perfect, so if you spot any bugs, just know that that is not perfect. We're going to perfect it in the next step. So, just create the useSearchParams hook, use that useSearchParams hook in the app, and then we'll move on from there.

Advanced React APIs covers many of the React APIs that you might not see on a day-to-day basis but you will need these in your toolbelt for certain scenarios that pop up.

We'll take a tour of several advanced hooks and React API, their use-cases, and when to use them. 

These will include:

- useReducer
- use
- createContext
- useLayoutEffect
- useImperativeHandle
- useSyncExternalStore
- flushSync
- createPortal


## Complex State Management

First we'll dive into the deep-end of state management with `useReducer`. This hook comes in really handy when you feel the logic in your components is a sprawling mess and you'd like to consolidate that into a single place with a nice API to interact with. 

We'll get into some state optimizations as well as how to make your logic easily sharable throughout your application with custom hooks.

## Context

While context is often times something you will leave up to library authors, there are some cases where you want to expose values you need throughout your application. We'll build a context provider that will expose search params to our components on a blog search page with `use` (previously `useContext`) and `createContext`.

You'll also refactor this code to expose the context you create in a custom hook that will give us nice error handling when context isn't set up correctly.

## Portals

React gives us `createPortal` to render UI outside of the DOM tree structure that a component might sit in. This is useful for UI elements like modals or tooltips. We'll explore how to attach a tooltip to the `document.body` to ensure it's positioned where it needs to go.

## Layout Computations

If the logic that you are working with in a `useEffect` affects the how the UI looks, especially on first render, you'll want to `useLayoutEffect`. You'll work through an exercise where the client makes calculations on where to place a tooltip before rendering and see the difference when this is in a `useLayoutEffect`.

## Imperative Handles

`useImperativeHandle` is an escape hatch in React that lets you imperatively tell React what to do. This hook is typically paired with a ref (from `useRef`) where we want to expose imperative methods to developers who pass a ref prop to our components.

## Focus Management

`flushSync` is technically a 'de-optimization' because it forces React to re-render whenever you call it. This means you need to be very careful and know what you're doing when you use it.

The primary use-case for this API is focus management. When you have conditional UI that gets rendered based on various state conditions, you can `flushSync` to ensure elements are in the DOM to properly focus.

## Sync Exernal Store

There are some cases where we want to synce our React code with the external world and display different UI based on the state of the external world. This is where `useSyncExternalStore` is useful and lets you subscribe to external stores. We'll also touch on server rendering as this hook supports that use-case.

Learn the hooks and API that React has to offer for complex state management, sharing context throughout your app, focus management and more.

Advanced React APIs

Kent C. Dodds

React Fundamentals

React Hooks

React Suspense

Advanced React Patterns

React Performance

React Server Components

Epic React Pro

Advanced React APIs Intro

Intro to Advanced State Management

New State

Previous State

State Object

Action Function

Traditional Reducer

Real World

Dad Joke Break Advanced State Management

Advanced State Management

Intro to State Optimization

Optimize state updates

Dad Joke Break State Optimization

State Optimization

Intro to Custom Hooks

useCallback

Dad Joke Break Custom Hooks 

Custom Hooks

Intro to Shared Context 

Context Provider

Context Hook

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Shared Context

Intro to Portals

createPortal

Dad Joke Break Portals 

Portals

Intro to Layout Computation 

useLayoutEffect

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Layout Computation

Intro to Imperative Handles

useImperativeHandle

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Imperative Handles 

Intro to Focus Management 

flushSync

Dad Joke Break Focus Management 

Focus Management

Intro to Sync External State 

useSyncExternalStore

Make Store Utility

Handling Server Rendering

Dad Joke Break Sync External State

Sync External State

Outro to Advanced React APIs

Advanced React APIs

Advanced React APIs

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Hook Function

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