React Fundamentals

React Course

My React Course

Support

Find the Content Useful? You can always buy me a coffee

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 />);

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

• Javascript Nuggets - Map

• refactor

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

• render component
• pass entire object
• Destructuring (object) JS Nuggets - Destructuring (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

• utilize spread operator (...) - copy values
• Spread Operator
• JS Nuggets - Spread Operator

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