Intro to Custom Components

[00:00] It's time to talk about custom components. Here's the deal. React components are functions which accept an object and return something that is renderable. That's it. That's the entire definition of a custom component. There's nothing special about them at all. It's just a function, accepts an object to props,

[00:17] returns something that you can render. And typically those things that are renderable are other React elements, but you could even return a string, and that is technically a React component. You can create an element out of that. The idea behind a custom component is it's a thing that you can pass to the create element API.

[00:36] And there's a special syntax in JSX that allows you to represent that custom component in the JSX that we're going to be exploring in this exercise. So here's a very simple example of a custom component. It's a function called greeting. It takes the props objects,

[00:55] and those props can then be passed by whoever is trying to render that particular component. So that's what you're going to be doing in this exercise. We're going to be exploring custom components through an iterative process to get us closer and closer to the actual API.

[01:12] So you understand exactly how JSX is compiling into the calling of these functions, and how React ends up calling those functions. It's kind of interesting how all of that works together. And then finally, we'll see how this can be practically useful in the last exercise. So have a good time, we'll see you when you're done.

Learn everything you need to be effective with the fundamental building blocks of React applications. 

The path of this workshop takes you from the fundamental API of appending DOM nodes, through React's raw APIs, to how JSX compiles into React's methods.

Once you have a firm grasp of what React is doing with creating elements, you'll learn the other tools you need to build webpages like: styling, forms, and inputs. 

But, this isn't just a native web course. 

**You'll be building a strong foundation in React.** 

Learn how to: 

- build reusable components
- leverage TypeScript with React
- catch errors with Error Boundaries
- render arrays properly with the `key` prop. 

When you’re finished, you’ll be prepared to create and use React components to build excellent experiences for your app's users.

## Hello World in JS

You'll start your journey by learning some of the history of how we went from generating HTML on the server and adding JS on top to full-fledged frameworks. 

To learn React you'll be following a similar path and begin by learning how to manually append your own DOM nodes.

I call this "going down to level up." You'll find yourself much more efficient with React if you understand the fundamentals of the DOM and JavaScript!

## Raw React APIs

Before getting into JSX, you'll learn how to work with React and ReactDOM's raw APIs. 

You'll create React elements with `React.createElement` and learn how compose your elements with calls to this function. Then, you'll render the React elements you create using ReactDOM.

## Using JSX

Once you know what React is doing under the hood, you'll be prepared to learn JSX.

This section covers more than just how to write it, you'll also use babel to experiement with how JSX gets compiled to the raw React APIs!

## Custom Components

Just like in regular JavaScript, when you want to reuse code, you write functions. If you want to share JSX, you can do that as well. 

In this section you'll learn about how in React, we call these functions "components", the special properties of these functions, and how to 

## TypeScript

> TypeScript is not making your life terrible. It's just showing you how terrible your life already is. 
 
*- Kent C. Dodds*

Getting a solid hold of TypeScript from the get-go will set you up for success. Since React components are just functions, there aren't any special considerations when applying type annotations. 

So, you'll be working on two things:

1. Improving your TypeScript skills
2. Learning the React-specific types available

## Styling

In this section you'll learn about the two primary ways to style React components:

1. Inline styles with the `style` prop
2. Regular CSS with the `className` prop

You'll also learn why React uses a `className` prop instead of `class`. 👀

## Forms

In React, there actually aren't a ton of things you have to learn to interact with forms beyond what you can do with regular DOM APIs and JavaScript.

Here, you'll learn the form markup, build an onSubmit handler, and then create a form action. 

## Inputs

There's a ton of different input types and you're going to learn a lot about them here!

You'll learn about the different text inputs, check boxes, radios, hidden inputs, how to make sure everything is properly labeled and accessible, and setting default values and default checked boxes. 

## Error Boundaries

This is something you want to learn early on. Sometimes things go wrong and we need to handle errors and display useful information to the user. 

An ErrorBoundary component doesn't ship with React by default. So, you'll be importing one from react-error-boundry and then learning how to compose it, and then give the option to the user to reset. 

## Rendering Arrays

In React you can render arrays of elements. One of the tricky parts about it is the `key` prop. 

In this section, you'll learn in detail why React needs the `key` prop to keep track of elements and the nuances of the value that is used. 

Finally, you'll learn a cool trick where the `key` prop is used as a mechanism for resetting elements in the DOM!


Starting with an HTML file and a script, you'll learn React API to build components and manage forms. Learn the fundamentals of building on the web with React.

React Fundamentals

Kent C. Dodds

React Hooks

Advanced React APIs

React Suspense

Advanced React Patterns

React Performance

React Server Components

Interviews With Experts

Epic React Pro

React Fundamentals Intro

Intro

Hello World in JS

Generate the Root Node

Dad Joke Break

Intro to Raw React APIs

Create React Elements

Nesting Elements

Deep Nesting Elements

Dad Joke Break Raw React APIs

Raw React APIs

Intro to Using JSX

Compiling JSX

Interpolation

Spread props

Nesting JSX

Fragments

Dad Joke Break Using JSX

Using JSX

Simple Function

Raw API

JSX Components

Props

Dad Joke Break Custom Components

Custom Components

Intro to TypeScript

Narrow Types

Derive Types

Default Props

Reduce Duplication

Satisfies

Dad Joke Break TypeScript

TypeScript

Intro to Styling

Styling

Custom Component

Size Prop

Dad Joke Break Styling

Intro to Forms

Form

Form Action

Input Types

Submission

Form Actions

Dad Joke Break Forms

Forms

Intro to Inputs

Checkbox

Select

Radios

Hidden Inputs

Default Value

Dad Joke Break Inputs

Inputs

Intro to Error Boundaries

Composition

Other Errors

Reset

Dad Joke Break Error Boundaries

Error Boundaries

Intro to Rendering Arrays

Key prop

Focus State

Key Reset

Dad Joke Break Rendering Arrays

Rendering Arrays

Outro to React Fundamentals 

React Fundamentals

React Fundamentals

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Intro to Custom Components

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