Skip to content

romashka-dev/react-fundamentals

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

18 Commits
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

React Fundamentals

Netlify Status

React Course: Complete React, Next.js & TypeScript Projects Course 2024 (Created by John Smilga)

Link

Folder Structure

  • node_modules Contains all dependencies required by the app. Main dependencies also listed in package.json

  • public Contains static assets including index.html (page template)

    • index.html
      • title
      • fonts
      • css
      • favicon
      • id="root" - our entire app
  • src In simplest form it's the brain of our app. This is where we will do all of our work. src/index.js is the JavaScript entry point.

  • .gitignore Specifies which files source control (Git) should ignore

  • package.json Every Node.js project has a package.json and it contains info about our project, for example list of dependencies and scripts

  • package-lock.json A snapshot of the entire dependency tree

  • README The markdown file where you can share more info about the project for example build instructions and summary

  • zoom 175%

Remove Boilerplate

  • remove src folder

  • create src folder

    • create index.js inside src
  • toggle sidebar CMD + B

  • shortcuts settings/keyboard shortcuts

First Component

function Greeting() {
  return <h2>My First Component</h2>
}

// arrow function also works

const Greeting = () => {
  return <h2>My First Component</h2>
}
  • starts with capital letter
  • must return JSX (html)
  • always close tag
Typical Component
// imports or logic

const Greeting = () => {
  return <h2>My First Component</h2>
}
export default Greeting
Root Component (only one)

index.js

import React from 'react'
import ReactDOM from 'react-dom/client'

function Greeting() {
  return <h2>My First Component</h2>
}

const root = ReactDOM.createRoot(document.getElementById('root'))

root.render(<Greeting />)

Possible Bug

If for some reason you still have this error in the terminal

Module not found: Error: Can't resolve 'path/index.js'

Just restart the server

  • CTRL + C (stop the server)
  • "npm start" (start the dev server)

Extensions and settings.json

  • Auto Rename Tag
  • Highlight Matching Tag
    • customize in settings.json
  • Prettier
    • format on save
    • format on paste
    • Default Formatter (Prettier - Code formatter)

settings.json

  "editor.formatOnPaste": true,
  "editor.formatOnSave": true,
  "editor.defaultFormatter": "esbenp.prettier-vscode",
    "prettier.singleQuote": true,
    "prettier.semi": false,
  • Emmet

settings.json

"emmet.includeLanguages": {
    "javascript": "javascriptreact"
  },
  • ES7 Snippets
    • rafce (arrow func with export)
    • rfce (regular func with export )
    • same as the file name
    • react auto import
      • uncheck
      • React Snippets › Settings: Import React On Top

First Component in Detail

  • capital letter
  • must return something
  • JSX syntax (return html)
    • to make our lives easier
    • calling function under the hood

index.js

const Greeting = () => {
  return React.createElement('h2', {}, 'hello world')
}
function Greeting() {
  return (
    <div>
      <h2>hello world</h2>
    </div>
  )
}

const Greeting = () => {
  return React.createElement(
    'div',
    {},
    React.createElement('h2', {}, 'hello world')
  )
}

JSX Rules

  • return single element (one parent element)

    • semantics section/article
    • Fragment - let's us group elements without adding extra nodes
return <React.Fragment>...rest of the return</React.Fragment>

// shorthand

return <>...rest of the return</>
  • camelCase property naming convention
return (
  <div tabIndex={1}>
    <button onClick={myFunction}>click me</button>
    <label htmlFor='name'>Name</label>
    <input readOnly={true} id='name' />
  </div>
)
// in html
<div tabindex="1">
    <button onclick="myFunction()">click me</button>
    <label for='name'>Name</label>
    <input readonly id='name' />
</div>
  • className instead of class
return <div className="someValue">hello</div>
  • close every element
return <img />
// or
return <input />
  • formatting
    • opening tag in the same line as return or ()
function Greeting() {
  return (
    <>
      <div className="someValue">
        <h3>hello people</h3>
        <ul>
          <li>
            <a href="#">hello world</a>
          </li>
        </ul>
      </div>
      <h2>hello world</h2>
      <input type="text" name="" id="" />
    </>
  )
}

Nest Components

function Greeting() {
  return (
    <div>
      <Person />
      <Message />
    </div>
  )
}

const Person = () => <h2>john doe</h2>
const Message = () => {
  return <p>this is my message</p>
}

React Developer Tools

  • top right corner
  • more tools/extensions
  • open chrome web store

Book List

  • setup structure
import React from 'react'
import ReactDOM from 'react-dom/client'

function BookList() {
  return (
    <section>
      <Book />
      <Book />
      <Book />
      <Book />
    </section>
  )
}

const Book = () => {
  return (
    <article>
      <Image />
      <Title />
      <Author />
    </article>
  )
}

const Image = () => <h2>image placeholder</h2>
const Title = () => {
  return <h2>Book Title</h2>
}
const Author = () => <h4>Author</h4>

const root = ReactDOM.createRoot(document.getElementById('root'))

root.render(<BookList />)
  • in search engine type - 'amazon best selling books' Amazon Best Sellers
  • DON'T NEED TO BUY ANYTHING !!!
  • NOT AN AFFILIATE LINK !!!!
  • choose a book
  • copy image, title and author
import React from 'react'
import ReactDOM from 'react-dom/client'

function BookList() {
  return (
    <section>
      <Book />
      <Book />
      <Book />
      <Book />
    </section>
  )
}

const Book = () => {
  return (
    <article className="book">
      <Image />
      <Title />
      <Author />
    </article>
  )
}

const Image = () => (
  <img
    src="https://images-na.ssl-images-amazon.com/images/I/71m+Qtq+HrL._AC_UL900_SR900,600_.jpg"
    alt="Interesting Facts For Curious Minds"
  />
)
const Title = () => {
  return <h2>Interesting Facts For Curious Minds</h2>
}
const Author = () => <h4>Jordan Moore </h4>

const root = ReactDOM.createRoot(document.getElementById('root'))

root.render(<BookList />)

CSS

  • create index.css in src
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
    Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
  background: #f1f5f8;
  color: #222;
}
  • import file and add classes
import './index.css'

function BookList() {
  return (
    <section className="booklist">
      <Book />
      <Book />
      <Book />
      <Book />
    </section>
  )
}

const Book = () => {
  return (
    <article className="book">
      <Image />
      <Title />
      <Author />
    </article>
  )
}
  • complete css
.booklist {
  width: 90vw;
  max-width: 1170px;
  margin: 5rem auto;
  display: grid;
  gap: 2rem;
}

@media screen and (min-width: 768px) {
  .booklist {
    grid-template-columns: repeat(3, 1fr);
  }
}
.book {
  background: #fff;
  border-radius: 1rem;
  padding: 2rem;
  text-align: center;
}
.book img {
  width: 100%;
  object-fit: cover;
}
.book h2 {
  margin-top: 1rem;
  font-size: 1rem;
}

Local Images (Public Folder)

  • Optional Video !!!

  • external images (hosted on different server) - just need an url

  • local images (public folder) - less performant

  • local images (src folder) - better solution for assets, since under the hood they get optimized.

  • save image (Save Image As....)

  • create images folder in public

  • copy/paste image

  • rename (optional)

  • replace url in the src - './images/imageName.extension'

  • './' because assets are on the same server

const Image = () => (
  <img src="./images/book-1.jpg" alt="Interesting Facts For Curious Minds" />
)
  • whatever assets we place in public - instantly available
  • domain(localhost)/asset

JSX - CSS (inline styles)

  • style prop
  • {} in JSX means going back to JS Land
  • value is an object with key/value pairs - capitalized and with ''
const Author = () => (
  <h4 style={{ color: '#617d98', fontSize: '0.75rem', marginTop: '0.5rem' }}>
    Jordan Moore
  </h4>
)
  • css rules still apply (inline vs external css)
.book h4 {
  /* won't work */
  color: red;
  /* will work */
  letter-spacing: 2px;
}
  • external libraries use inline css, so if you want to make some changes, reference the library docs and elements tab

  • alternative option

const Author = () => {
  const inlineHeadingStyles = {
    color: '#617d98',
    fontSize: '0.75rem',
    marginTop: '0.5rem',
  }
  return <h4 style={inlineHeadingStyles}>Jordan Moore </h4>
}
  • FOR THE MOST PART, MULTIPLE APPROACHES AVAILABLE !!!
  • AS LONG AS THE RESULT IS THE SAME, REALLY COMES DOWN TO PREFERENCE !!!!

JSX - Javascript

  • refactor to single book component (personal preference)
  • remove inline css
const Book = () => {
  return (
    <article className="book">
      <img
        src="./images/book-1.jpg"
        alt="Interesting Facts For Curious Minds"
      />
      <h2>Interesting Facts For Curious Minds</h2>
      <h4>Jordan Moore </h4>
    </article>
  )
}
.book h4 {
  color: #617d98;
  font-size: 0.75rem;
  margin-top: 0.5rem;
  letter-spacing: 2px;
}
  • {} in JSX means going back to JS Land
  • value inside must be an expression (return value), can't be a statement
const author = 'Jordan Moore'
const Book = () => {
  const title = 'Interesting Facts For Curious Mindssssss'
  return (
    <article className="book">
      <img
        src="./images/book-1.jpg"
        alt="Interesting Facts For Curious Minds"
      />
      <h2>{title}</h2>

      <h4>{author.toUpperCase()} </h4>
      {/* <p>{let x = 6}</p> */}
      <p>{6 + 6}</p>
    </article>
  )
}
  • toggle line comment Edit/Toggle Line Comment

Props - Initial Setup

  • refactor/clean up
const author = 'Jordan Moore'
const title = 'Interesting Facts For Curious Minds'
const img = './images/book-1.jpg'

function BookList() {
  return (
    <section className="booklist">
      <Book />
      <Book />
    </section>
  )
}
const Book = () => {
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
    </article>
  )
}
// parameters
const someFunc = (param1, param2) => {
  console.log(param1, param2)
}
// arguments
someFunc('job', 'developer')
const Book = (props) => {
  console.log(props)
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
      {console.log(props)}
    </article>
  )
}
  • props object, convention to call props, 'shakeAndBake' is an excellent alternative

  • pass as key/value pairs

  • if the prop exists it will return value, otherwise no value

function BookList() {
  return (
    <section className="booklist">
      <Book job="developer" />
      <Book title="random title" number={22} />
    </section>
  )
}
const Book = (props) => {
  console.log(props)
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
      <p>{props.job}</p>
      <p>{props.title}</p>
      <p>{props.number}</p>
    </article>
  )
}
function BookList() {
  return (
    <section className="booklist">
      <Book author={author} title={title} img={img} />
      <Book title={title} img={img} />
    </section>
  )
}
const Book = (props) => {
  console.log(props)
  return (
    <article className="book">
      <img src={props.img} alt={props.title} />
      <h2>{props.title}</h2>
      <h4>{props.author} </h4>
    </article>
  )
}

Props - Somewhat Dynamic Setup

  • setup an object
  • refactor vars to properties
  • copy/paste and rename
  • get values for second book
  • setup props
const firstBook = {
  author: 'Jordan Moore',
  title: 'Interesting Facts For Curious Minds',
  img: './images/book-1.jpg',
}
const secondBook = {
  author: 'James Clear',
  title: 'Atomic Habits',
  img: 'https://images-na.ssl-images-amazon.com/images/I/81wgcld4wxL._AC_UL900_SR900,600_.jpg',
}

function BookList() {
  return (
    <section className="booklist">
      <Book
        author={firstBook.author}
        title={firstBook.title}
        img={firstBook.img}
      />
      <Book
        author={secondBook.author}
        title={secondBook.title}
        img={secondBook.img}
      />
    </section>
  )
}
const Book = (props) => {
  console.log(props)
  return (
    <article className="book">
      <img src={props.img} alt={props.title} />
      <h2>{props.title}</h2>
      <h4>{props.author} </h4>
    </article>
  )
}

Access Props - Multiple Approaches

  • there is no right or wrong - again preference !!!

  • Destructuring (object) JS Nuggets - Destructuring (object)

  • destructuring in Vanilla JS

  • saves time/typing

  • pull out the properties

  • don't need to reference object anymore

const someObject = {
  name: 'john',
  job: 'developer',
  location: 'florida',
}

console.log(someObject.name)
const { name, job } = someObject
console.log(job)
  • no need for all the props.propName
  • destructure inside component
const Book = (props) => {
  const { img, title, author } = props
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
    </article>
  )
}
  • destructure in function parameters (in our case props)
  • if you have console.log(props) - it won't be defined
const Book = ({ img, title, author }) => {
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
    </article>
  )
}

Children Prop

  • everything we render between component tags
  • during the course we will mostly use it Context API
  • special prop, has to be "children"
  • can place anywhere in JSX
function BookList() {
  return (
    <section className="booklist">
      <Book
        author={firstBook.author}
        title={firstBook.title}
        img={firstBook.img}
      >
        <p>
          Lorem ipsum dolor, sit amet consectetur adipisicing elit. Itaque
          repudiandae inventore eos qui animi sed iusto alias eius ea sapiente.
        </p>
        <button>click me</button>
      </Book>
      <Book
        author={secondBook.author}
        title={secondBook.title}
        img={secondBook.img}
      />
    </section>
  )
}

const Book = ({ img, title, author, children }) => {
  // rest of the logic
}
const Book = (props) => {
  const { img, title, author, children } = props
  console.log(props)
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
      {children}
    </article>
  )
}
  • optional
@media screen and (min-width: 768px) {
  .booklist {
    grid-template-columns: repeat(3, 1fr);
    align-items: start;
  }
}
.book p {
  margin: 1rem 0 0.5rem;
}

Simple List

const books = [
  {
    author: 'Jordan Moore',
    title: 'Interesting Facts For Curious Minds',
    img: './images/book-1.jpg',
  },
  {
    author: 'James Clear',
    title: 'Atomic Habits',
    img: 'https://images-na.ssl-images-amazon.com/images/I/81wgcld4wxL._AC_UL900_SR900,600_.jpg',
  },
]

function BookList() {
  return <section className="booklist"></section>
}

const Book = (props) => {
  const { img, title, author } = props

  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
    </article>
  )
}
  • can't render objects in React
function BookList() {
  return <section className="booklist">{books}</section>
}
  • map - creates a new array from calling a function for every array element.
const names = ['john', 'peter', 'susan']
const newNames = names.map((name) => {
  console.log(name)
  return <h1>{name}</h1>
})

function BookList() {
  return <section className="booklist">{newNames}</section>
}

Proper List

  • remove names and newNames
function BookList() {
  return (
    <section className="booklist">
      {books.map((book) => {
        console.log(book)

        // return 'hello';
        return (
          <div>
            <h2>{book.title}</h2>
          </div>
        )
      })}
    </section>
  )
}
  • render component
  • pass properties one by one
function BookList() {
  return (
    <section className="booklist">
      {books.map((book) => {
        console.log(book)
        const { img, title, author } = book
        return <Book img={img} title={title} author={author} />
      })}
    </section>
  )
}

Key Prop

  • typically it's going to be id
const books = [
  {
    author: 'Jordan Moore',
    title: 'Interesting Facts For Curious Minds',
    img: './images/book-1.jpg',
    id: 1,
  },
  {
    author: 'James Clear',
    title: 'Atomic Habits',
    img: 'https://images-na.ssl-images-amazon.com/images/I/81wgcld4wxL._AC_UL900_SR900,600_.jpg',
    id: 2,
  },
]

function BookList() {
  return (
    <section className="booklist">
      {books.map((book) => {
        console.log(book)
        const { img, title, author, id } = book
        return <Book book={book} key={id} />
      })}
    </section>
  )
}
  • you will see index,but it's not advised if the list is changing
function BookList() {
  return (
    <section className="booklist">
      {books.map((book, index) => {
        console.log(book)
        const { img, title, author, id } = book
        return <Book book={book} key={index} />
      })}
    </section>
  )
}

Pass The Entire Object

function BookList() {
  return (
    <section className="booklist">
      {books.map((book) => {
        console.log(book)
        const { img, title, author } = book
        return <Book book={book} />
      })}
    </section>
  )
}

const Book = (props) => {
  const { img, title, author } = props.book

  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
    </article>
  )
}
  • alternative
const Book = ({ book: { img, title, author } }) => {
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
    </article>
  )
}

My Personal Preference

const friends = ['john', 'peter', 'anna']
const newFriends = [...friends, 'susan']
console.log(friends)
console.log(newFriends)
const someObject = {
  name: 'john',
  job: 'developer',
}
// COPY NOT A REFERENCE !!!!
const newObject = { ...someObject, location: 'florida' }
console.log(someObject)
console.log(newObject)
function BookList() {
  return (
    <section className="booklist">
      {books.map((book) => {
        return <Book {...book} key={book.id} />
      })}
    </section>
  )
}

const Book = (props) => {
  const { img, title, author } = props
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <h4>{author} </h4>
    </article>
  )
}
const Book = ({ img, title, author }) => {
  // rest of the code
}

Events - Fundamentals

  • Vanilla JS
const btn = document.getElementById('btn')

btn.addEventListener('click', function (e) {
  // access event object
  // do something when event fires
})
  • similar approach
  • element, event, function
  • again camelCase
const EventExamples = () => {
  const handleButtonClick = () => {
    alert('handle button click')
  }
  return (
    <section>
      <button onClick={handleButtonClick}>click me</button>
    </section>
  )
}
  • React Events
  • no need to memorize them(idea is the same)
  • most common
    • onClick (click events)
    • onSubmit (submit form )
    • onChange (input change )
function BookList() {
  return (
    <section className="booklist">
      <EventExamples />
      {books.map((book) => {
        return <Book {...book} key={book.id} />
      })}
    </section>
  )
}

const EventExamples = () => {
  const handleFormInput = () => {
    console.log('handle form input')
  }
  const handleButtonClick = () => {
    alert('handle button click')
  }
  return (
    <section>
      <form>
        <h2>Typical Form</h2>
        <input
          type="text"
          name="example"
          onChange={handleFormInput}
          style={{ margin: '1rem 0' }}
        />
      </form>
      <button onClick={handleButtonClick}>click me</button>
    </section>
  )
}

Event Object and Form Submission

const EventExamples = () => {
  const handleFormInput = (e) => {
    console.log(e)
    // e.target - element
    console.log(`Input Name : ${e.target.name}`)
    console.log(`Input Value : ${e.target.value}`)
    // console.log('handle form input');
  }
  const handleButtonClick = () => {
    alert('handle button click')
  }
  const handleFormSubmission = (e) => {
    e.preventDefault()
    console.log('form submitted')
  }
  return (
    <section>
      {/* add onSubmit Event Handler */}
      <form onSubmit={handleFormSubmission}>
        <h2>Typical Form</h2>
        <input
          type="text"
          name="example"
          onChange={handleFormInput}
          style={{ margin: '1rem 0' }}
        />
        {/* add button with type='submit' */}
        <button type="submit">submit form</button>
      </form>
      <button onClick={handleButtonClick}>click me</button>
    </section>
  )
}
  • alternative approach
<button type="submit" onClick={handleFormSubmission}>
  submit form
</button>

Mind Grenade

  • alternative approach
  • pass anonymous function (in this case arrow function)
  • one liner - less code
const EventExamples = () => {
  return (
    <section>
      <button onClick={() => console.log('hello there')}>click me</button>
    </section>
  )
}
  • also can access event object
const EventExamples = () => {
  return (
    <section>
      <form>
        <h2>Typical Form</h2>
        <input
          type="text"
          name="example"
          onChange={(e) => console.log(e.target.value)}
          style={{ margin: '1rem 0' }}
        />
      </form>
      <button onClick={() => console.log('you clicked me')}>click me</button>
    </section>
  )
}

Mind Grenade #2

  • remove EventsExamples
  • components are independent by default
function BookList() {
  return (
    <section className="booklist">
      {books.map((book) => {
        return <Book {...book} key={book.id} />
      })}
    </section>
  )
}

const Book = (props) => {
  const { img, title, author } = props
  const displayTitle = () => {
    console.log(title)
  }

  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <button onClick={displayTitle}>display title</button>
      <h4>{author} </h4>
    </article>
  )
}
  • remove button

Prop Drilling

  • react data flow - can only pass props down
  • alternatives Context API, redux, other state libraries
function BookList() {
  const someValue = 'shakeAndBake'
  const displayValue = () => {
    console.log(someValue)
  }
  return (
    <section className="booklist">
      {books.map((book) => {
        return <Book {...book} key={book.id} displayValue={displayValue} />
      })}
    </section>
  )
}

const Book = (props) => {
  const { img, title, author, displayValue } = props

  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <button onClick={displayValue}>click me</button>
      <h4>{author} </h4>
    </article>
  )
}

More Complex Example

  • initial setup
  • create getBook function in booklist
  • accepts id as an argument and finds the book
  • Javascript Nuggets - Filter and Find
  • pass the function down to Book Component and invoke on the button click
  • in the Book Component destructure id and function
  • invoke the function when user clicks the button, pass the id
  • the goal : you should see the same book in the console
const BookList = () => {
  const getBook = (id) => {
    const book = books.find((book) => book.id === id)
    console.log(book)
  }

  return (
    <section className="booklist">
      {books.map((book) => {
        return <Book {...book} key={book.id} getBook={getBook} />
      })}
    </section>
  )
}

const Book = (props) => {
  const { img, title, author, getBook, id } = props
  // console.log(props);

  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      {/* this is not going to work */}
      <button onClick={getBook(id)}>display title</button>
      <h4>{author}</h4>
    </article>
  )
}
  • two fixes
  • first option - setup wrapper
const Book = (props) => {
  const { img, title, author, getBook, id } = props
  // console.log(props);
  const getSingleBook = () => {
    getBook(id)
  }
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>
      <button onClick={getSingleBook}>display title</button>
      <h4>{author}</h4>
    </article>
  )
}
  • two fixes
  • second option - wrap in the anonymous arrow function
const Book = (props) => {
  const { img, title, author, getBook, id } = props
  // console.log(props);
  const getSingleBook = () => {
    getBook(id)
  }
  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>

      <button onClick={() => getBook(id)}>display title</button>
      <h4>{author}</h4>
    </article>
  )
}

Import and Export Statements

  • remove all getBook code
function BookList() {
  return (
    <section className="booklist">
      {books.map((book) => {
        return <Book {...book} key={book.id} />
      })}
    </section>
  )
}

const Book = (props) => {
  const { img, title, author } = props

  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>

      <h4>{author} </h4>
    </article>
  )
}
  • setup two files in src books.js and Book.js
  • cut books array from index.js
  • add to books.js

books.js

const books = [
  {
    author: 'Jordan Moore',
    title: 'Interesting Facts For Curious Minds',
    img: './images/book-1.jpg',
    id: 1,
  },
  {
    author: 'James Clear',
    title: 'Atomic Habits',
    img: 'https://images-na.ssl-images-amazon.com/images/I/81wgcld4wxL._AC_UL900_SR900,600_.jpg',
    id: 2,
  },
]
  • two flavors named and default exports

    • with named exports names MUST match
    • with default exports,can rename but only one per file
  • named export

export const books = [
  {
    author: 'Jordan Moore',
    title: 'Interesting Facts For Curious Minds',
    img: './images/book-1.jpg',
    id: 1,
  },
  {
    author: 'James Clear',
    title: 'Atomic Habits',
    img: 'https://images-na.ssl-images-amazon.com/images/I/81wgcld4wxL._AC_UL900_SR900,600_.jpg',
    id: 2,
  },
]

index.js

import { books } from './books'
  • default export
const Book = (props) => {
  const { img, title, author } = props

  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>

      <h4>{author} </h4>
    </article>
  )
}

export default Book

index.js

import Book from './Book'

Local Images (src folder)

  • better performance because optimized
  • add one more book to array
  • download all three images (rename)
  • setup images folder in the src
  • import all three images in the books.js
  • set image property equal to import
  • and yes each image requires new import
import img1 from './images/book-1.jpg'
import img2 from './images/book-2.jpg'
import img3 from './images/book-3.jpg'

export const books = [
  {
    author: 'Jordan Moore',
    title: 'Interesting Facts For Curious Minds',
    img: img1,
    id: 1,
  },
  {
    author: 'James Clear',
    title: 'Atomic Habits',
    img: img2,
    id: 2,
  },
  {
    author: 'Stephen King',
    title: 'Fairy Tale',
    img: img3,
    id: 3,
  },
]

Challenges

  • setup numbers
  • don't worry about css
  • hint - index (second parameter in map)

index.js

const BookList = () => {
  return (
    <section className="booklist">
      {books.map((book, index) => {
        return <Book {...book} key={book.id} number={index} />
      })}
    </section>
  )
}

const Book = (props) => {
  const { img, title, author, number } = props

  return (
    <article className="book">
      <img src={img} alt={title} />
      <h2>{title}</h2>

      <h4>{author}</h4>
      <span className="number">{`# ${number + 1}`}</span>
    </article>
  )
}

index.css

.book {
  background: #fff;
  border-radius: 1rem;
  padding: 2rem;
  text-align: center;
  /* set relative */
  position: relative;
}

.number {
  position: absolute;
  top: 0;
  left: 0;
  font-size: 1rem;
  padding: 0.75rem;
  border-top-left-radius: 1rem;
  border-bottom-right-radius: 1rem;
  background: #c35600;
  color: #fff;
}

Add Title

  • add a title to our app (css optional)
  • change page title

index.js

function BookList() {
  return (
    <>
      <h1>amazon best sellers</h1>
      <section className="booklist">
        {books.map((book) => {
          return <Book {...book} key={book.id} />
        })}
      </section>
    </>
  )
}

index.css

h1 {
  text-align: center;
  margin-top: 4rem;
  text-transform: capitalize;
}

public/index.html

<title>Best Sellers</title>

Build Production Application

  • stop the dev server "ctrl + c"
  • run "npm run build"
  • build folder gets created

Netlify

  • sign up
  • add new site/deploy manually
  • choose build folder
  • rename site - site settings/change site name