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Introduction to React

Sparking the REACTion of User Interface and Experience

dog

Decomposing the HTML User Interface

Complete code 
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<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css"
        integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous" />
    <link rel="stylesheet" href="style.css" />
    <title>My Home Page - Frinze Lapuz</title>
</head>

<body>
    <nav class="navbar sticky-top navbar-dark bg-dark">
        <div class="container nav">
            <a class="navbar-brand" href="#">Royal Homepage</a>
        </div>
    </nav>
    <div class="container">
        <div class="row">
            <div class="col">Here Some Dog For You. Cool Stuff right?</div>
            <div class="col">
                <!-- <img class="img-fluid img-thumbnail" src="dog.jpg" alt="dog" /> -->
                <div class="carouselWrapper">
                    <div id="carouselDoggo" class="carousel slide" data-ride="carousel">
                        <ol class="carousel-indicators">
                            <li data-target="#carouselDoggo" data-slide-to="0" class="active"></li>
                            <li data-target="#carouselDoggo" data-slide-to="1"></li>
                            <li data-target="#carouselDoggo" data-slide-to="2"></li>
                        </ol>
                        <div class="carousel-inner">
                            <div class="carousel-item active">
                                <img src="dog.jpg" class="d-block w-100" alt="..." />
                                <div class="carousel-caption d-none d-md-block">
                                    <h5>First Dog</h5>
                                    <p>Cutie :)</p>
                                </div>
                            </div>
                            <div class="carousel-item">
                                <img src="dog2.jpg" class="d-block w-100" alt="..." />
                                <div class="carousel-caption d-none d-md-block">
                                    <h5>Second Dog</h5>
                                    <p>Good Doggo!</p>
                                </div>
                            </div>
                            <div class="carousel-item">
                                <img src="dog3.jpg" class="d-block w-100" alt="..." />
                                <div class="carousel-caption d-none d-md-block">
                                    <h5>Third Dog</h5>
                                    <p>Walkie Barkie Cutie!</p>
                                </div>
                            </div>
                        </div>
                        <a class="carousel-control-prev" href="#carouselDoggo" data-slide="prev">
                            <span class="carousel-control-prev-icon"></span>
                            <span class="sr-only">Previous</span>
                        </a>
                        <a class="carousel-control-next" href="#carouselDoggo" data-slide="next">
                            <span class="carousel-control-next-icon"></span>
                            <span class="sr-only">Next</span>
                        </a>
                    </div>
                </div>
            </div>
        </div>
    </div>
    <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"
        integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo"
        crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js"
        integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1"
        crossorigin="anonymous"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"
        integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM"
        crossorigin="anonymous"></script>
</body>

</html>
Relevant Code for Discussion 
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<nav class="navbar sticky-top navbar-dark bg-dark"> <!--(1)-->
    <div class="container nav">
        <a class="navbar-brand" href="#">Royal Homepage</a>  
    </div>
</nav>
<div class="container">
    <div class="row">
        <div class="col">Here Some Dog For You. Cool Stuff right?</div> <!--(2)-->
        <div class="col">
            <div class="carouselWrapper"> <!--(3)-->
                <div id="carouselDoggo" class="carousel slide" data-ride="carousel">
                    <ol class="carousel-indicators">
                        <li data-target="#carouselDoggo" data-slide-to="0" class="active"></li>
                        <li data-target="#carouselDoggo" data-slide-to="1"></li>
                        <li data-target="#carouselDoggo" data-slide-to="2"></li>
                    </ol>
                    <div class="carousel-inner">
                        <div class="carousel-item active">
                            <img src="dog.jpg" class="d-block w-100" alt="..." />
                            <div class="carousel-caption d-none d-md-block">
                                <h5>First Dog</h5>
                                <p>Cutie :)</p>
                            </div>
                        </div>
                        <div class="carousel-item">
                            <img src="dog2.jpg" class="d-block w-100" alt="..." />
                            <div class="carousel-caption d-none d-md-block">
                                <h5>Second Dog</h5>
                                <p>Good Doggo!</p>
                            </div>
                        </div>
                        <div class="carousel-item">
                            <img src="dog3.jpg" class="d-block w-100" alt="..." />
                            <div class="carousel-caption d-none d-md-block">
                                <h5>Third Dog</h5>
                                <p>Walkie Barkie Cutie!</p>
                            </div>
                        </div>
                    </div>
                    <a class="carousel-control-prev" href="#carouselDoggo" data-slide="prev">
                        <span class="carousel-control-prev-icon"></span>
                        <span class="sr-only">Previous</span>
                    </a>
                    <a class="carousel-control-next" href="#carouselDoggo" data-slide="next">
                        <span class="carousel-control-next-icon"></span>
                        <span class="sr-only">Next</span>
                    </a>
                </div>
            </div>
        </div>
    </div>
</div>
  1. Navigation Bar
  2. Some Text
  3. Carousel

HTML Stored in Variables

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const Nav = 
    `<nav class="navbar sticky-top navbar-dark bg-dark"> 
        <div class="container nav">
            <a class="navbar-brand" href="#">Royal Homepage</a>  
        </div>
    </nav>
    `

HTML Stored in Functions

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const Nav = (title) => 
    `
    <nav class="navbar sticky-top navbar-dark bg-dark"> 
        <div class="container nav">
            <a class="navbar-brand" href="#">${title}</a>  
        </div>
    </nav>
    `
Carousel Decomposition

The highlighted ones are the key-distinct data driven elements. 

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<div class="carouselWrapper">
    <div id="carouselDoggo" class="carousel slide" data-ride="carousel">
        <ol class="carousel-indicators">  <!--(1)-->
            <li data-target="#carouselDoggo" data-slide-to="0" class="active"></li>
            <li data-target="#carouselDoggo" data-slide-to="1"></li>
            <li data-target="#carouselDoggo" data-slide-to="2"></li>
        </ol>
        <div class="carousel-inner">
            <div class="carousel-item active"> <!--(2)-->
                <img src="dog.jpg" class="d-block w-100" alt="..." />
                <div class="carousel-caption d-none d-md-block">
                    <h5>First Dog</h5>
                    <p>Cutie :)</p>
                </div>
            </div>
            <div class="carousel-item">
                <img src="dog2.jpg" class="d-block w-100" alt="..." />
                <div class="carousel-caption d-none d-md-block">
                    <h5>Second Dog</h5>
                    <p>Good Doggo!</p>
                </div>
            </div>
            <div class="carousel-item">
                <img src="dog3.jpg" class="d-block w-100" alt="..." />
                <div class="carousel-caption d-none d-md-block">
                    <h5>Third Dog</h5>
                    <p>Walkie Barkie Cutie!</p>
                </div>
            </div>
        </div>
        <a class="carousel-control-prev" href="#carouselDoggo" data-slide="prev">
            <span class="carousel-control-prev-icon"></span>
            <span class="sr-only">Previous</span>
        </a>
        <a class="carousel-control-next" href="#carouselDoggo" data-slide="next">
            <span class="carousel-control-next-icon"></span>
            <span class="sr-only">Next</span>
        </a>
    </div>
</div>

  1. Carousel Indicators
  2. Carousel Items

Now, what if we have a variable called dogsData an array of objects (may come from fetch). 

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dogsData = [
    ...
    {
        imgSrc: "dog.jpg",
        title: "First Dog",
        caption: "Cutie :)"
    }
    ...
]


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const Carousel = (dogsData) =>
    `
    <div class="carouselWrapper"> <!--(1)-->
        <div id="carouselDoggo" class="carousel slide" data-ride="carousel">
            <ol class="carousel-indicators">
                ${dogsData.map((dog, index) => `<li data-target="#carouselDoggo" data-slide-to="${index}" class="${index === 0 ? 'active' : ''}"></li>`).join('')}
            </ol>
            <div class="carousel-inner">
                ${dogsData.map((dog, index) => `
                    <div class="carousel-item ${index === 0 ? 'active' : ''}">
                        <img src="${dog.imgSrc}" class="d-block w-100" alt="..." />
                        <div class="carousel-caption d-none d-md-block">
                            <h5>${dog.title}</h5>
                            <p>${dog.caption}</p>
                        </div>
                    </div>
                `).join('')}
            </div>
            <a class="carousel-control-prev" href="#carouselDoggo" data-slide="prev">
                <span class="carousel-control-prev-icon"></span>
                <span class="sr-only">Previous</span>
            </a>
            <a class="carousel-control-next" href="#carouselDoggo" data-slide="next">
                <span class="carousel-control-next-icon"></span>
                <span class="sr-only">Next</span>
            </a>
        </div>
    </div>
    `

Assemble the Components

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{Nav("Royal Homepage")}
<div class="container">
    <div class="row">
        <div class="col-md-12">
            {Carousel(dogsData)}
        </div>
    </div>
or with JSX

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<Nav title="Royal Homepage"></Nav>
<div class="container">
    <div class="row">
        <div class="col-md-12">
            <Carousel dogsData={dogsData}></Carousel>
        </div>
    </div>

Intro to React

Complete Modularised Code 
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const Nav = () => <nav class="navbar sticky-top navbar-dark bg-dark"> 
    <div class="container nav">
        <a class="navbar-brand" href="#">Royal Homepage</a>  
    </div>
</nav>

const Carousel = (dogsData) =>
    <div class="carouselWrapper">
        <div id="carouselDoggo" class="carousel slide" data-ride="carousel">
            <ol class="carousel-indicators">
                ${dogsData.map((dog, index) => `<li data-target="#carouselDoggo" data-slide-to="${index}" class="${index === 0 ? 'active' : ''}"></li>`).join('')}
            </ol>
            <div class="carousel-inner">
                ${dogsData.map((dog, index) => `
                    <div class="carousel-item ${index === 0 ? 'active' : ''}">
                        <img src="${dog.imgSrc}" class="d-block w-100" alt="..." />
                        <div class="carousel-caption d-none d-md-block">
                            <h5>${dog.title}</h5>
                            <p>${dog.caption}</p>
                        </div>
                    </div>
                `).join('')}
            </div>
            <a class="carousel-control-prev" href="#carouselDoggo" data-slide="prev">
                <span class="carousel-control-prev-icon"></span>
                <span class="sr-only">Previous</span>
            </a>
            <a class="carousel-control-next" href="#carouselDoggo" data-slide="next">
                <span class="carousel-control-next-icon"></span>
                <span class="sr-only">Next</span>
            </a>
        </div>
    </div>

const Homepage = () =>{
    const dogsData = fetch(...) // Get data from API
    return (
        <>
            <Nav title="Royal Homepage"></Nav>
            <div class="container">
                <div class="row">
                    <div class="col-md-12">
                        <Carousel dogsData={dogsData}></Carousel>
                    </div>
            </div>
        </>
    )
}

Getting Started with React

Getting Started with the app

To get started with react, use the following commands

npx create-react-app my-app where my-app is the name of the folder for where the react app is going to be.

cd my-app

Notice that it created a couple of folders. In a couple of sentences:

src/index.js - injects the user interface in the public/index.html (the front part of the build)

public - folder containing the static assets as well as the index.html

package.json - dependencies and scripts for the app

type yarn start to run the development version of React (it will run react-scripts start within the node_modules … so running react-scripts start will not exactly be the same). This will serve up React in a port

To be left as a live coding exercise. Live coding demonstration:

Demo

  • Passing Array props
  • show “rafce”
  • useState when adding new item