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<h1>The advantages of the template element</h1>
<section>
<h2>Using <code>document.createElement</code></h2>
<div id="container1" class="grid"></div>
</section>
<section>
<h2>Using <code><template></code></h2>
<div id="container2" class="grid"></div>
</section>
<!--
This template won't be rendered at first
It waits here until we clone it from our JS and append a copy to the page
-->
<template id="articleTemplate">
<article class="card">
<img alt="" class="card__image">
<div class="card__body">
<h3 class="card__title"></h3>
<p></p>
</div>
</article>
</template>
* {
box-sizing: border-box;
}
body {
max-width: 80rem;
margin: 0 auto; /* center the 80rem wide container within the page */
padding: 2rem;
font-family: system-ui;
}
section {
margin-top: 4rem;
}
.grid {
display: grid;
/* create an automatic grid that fits as many columns that are at least 14rem wide as possible */
grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
grid-gap: 2rem;
}
.card {
border-radius: 8px;
/* two layered box shadows give a more natural floaty effect */
box-shadow:
0 2px 2px hsla(180, 10%, 20%, 0.2),
0 8px 20px hsla(180, 10%, 20%, 0.3);
overflow: hidden; /* stop the image poking out of the top at the rounded corners */
}
.card__image {
width: 100%;
object-fit: cover; /* stops the image getting squished as the card's size changes */
}
.card__body {
padding: 1rem;
}
.card__title {
margin: 0;
line-height: 1;
text-transform: capitalize; /* make the first letter of each word uppercase */
}
// an array of data we want to render to the DOM
const articles = [
{
title: "my nice article",
summary:
"Lorem ipsum dolor sit amet consectetur adipisicing elit. Voluptatibus, omnis!",
image: "https://source.unsplash.com/400x300?0",
},
{
title: "another article",
summary:
"Lorem ipsum dolor sit amet consectetur adipisicing elit. Voluptatibus, omnis!",
image: "https://source.unsplash.com/400x300?1",
},
{
title: "so many articles",
summary:
"Lorem ipsum dolor sit amet consectetur adipisicing elit. Voluptatibus, omnis!",
image: "https://source.unsplash.com/400x300?2",
},
{
title: "my nice article",
summary:
"Lorem ipsum dolor sit amet consectetur adipisicing elit. Voluptatibus, omnis!",
image: "https://source.unsplash.com/400x300?3",
},
];
const containerElement1 = document.querySelector("#container1");
// this function uses standard createElement to do DOM manipulation
// it'll only get longer as we add more stuff to the card element 🙃
function createCard(article) {
const { title, summary, image } = article;
// create all the elements we need and set their properties based on the data passed in to this function
const articleElement = document.createElement("article");
articleElement.classList.add("card");
const bodyElement = document.createElement("div");
bodyElement.classList.add("card__body");
const titleElement = document.createElement("h2");
titleElement.textContent = title;
titleElement.classList.add("card__title");
const imageElement = document.createElement("img");
imageElement.src = image;
imageElement.alt = "";
imageElement.classList.add("card__image")
const summaryElement = document.createElement("p");
summaryElement.textContent = summary;
// put each child element into the parent <article>
articleElement.appendChild(imageElement);
bodyElement.appendChild(titleElement);
bodyElement.appendChild(summaryElement);
articleElement.appendChild(bodyElement);
// put the <article> onto the page
containerElement1.appendChild(articleElement);
}
const containerElement2 = document.querySelector("#container2");
// this function uses the <template> defined in the HTML
// it'll only get longer if we need to add more dynamic properties
function createCardUsingTemplate(article) {
const { title, summary, image } = article;
// get the template for articles (from the HTML)
const template = document.querySelector("#articleTemplate");
// clone the content of the template (returns a DocumentFragment)
const domFragment = template.content.cloneNode(true);
// we only need to add the dynamic properties inside the fragment
// since all the static ones (e.g. styling classNames) are set in the template
domFragment.querySelector("h3").textContent = title;
domFragment.querySelector("img").src = image;
domFragment.querySelector("p").textContent = summary;
// put the fragment onto the page
containerElement2.appendChild(domFragment);
}
articles.forEach(createCard);
articles.forEach(createCardUsingTemplate);
Also see: Tab Triggers