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<header class="sticky">
<label for="drawer-checkbox" class="button drawer-toggle"></label>
<span href="#" class="logo">Mock App</span>
</header>
<input type="checkbox" id="drawer-checkbox">
<div class="drawer">
<label for="drawer-checkbox" class="button drawer-toggle hide"></label>
<img src="https://unsplash.it/800/800?image=201"/>
<label for="drawer-checkbox" class="button" id="posts-view-button">Posts</label>
<label for="drawer-checkbox" class="button" id="users-view-button">Users</label>
<a href="https://medium.com/@chalarangelo/a-begginners-guide-to-progressive-web-apps-the-frontend-web-424b6d697e35" class="button" target="_blank">Tutorial</a>
</div>
<div class="container">
<div class="row cols-sm-12 cols-md-10 cols-lg-8" id="content-area"></div>
</div>
<footer>
<div class="row cols-sm-12 cols-md-10 cols-lg-8">
<div class="col-md-offset-1 col-lg-offset-2">
<p>This mock app was created as part of <a href="https://medium.com/@chalarangelo/a-begginners-guide-to-progressive-web-apps-the-frontend-web-424b6d697e35" target="_blank">this article</a>.</p>
</div>
</div>
</footer>
.container {
min-height: calc(100vh - 15rem);
}
h4.user-name, .user-location {
text-transform: capitalize;
}
h4.user-name small {
text-transform: lowercase;
}
svg {
vertical-align: middle;
}
.user-image {
min-width: 2.25rem;
margin-top: 0.5rem;
}
header .logo {
line-height: 1.625;
padding-left: 0.75rem;
}
.drawer {
overflow: visible;
}
.drawer label.drawer-toggle.hide{
height: 2.125rem;
width: 292px;
background: #283593;
border: 1px solid #283593;
color: #fafafa;
margin-left: -1px;
}
.drawer label.drawer-toggle.hide:hover, .drawer label.drawer-toggle.hide:focus{
background: #303f9f;
}
.drawer label.drawer-toggle.hide::before {
content: '\00a0\00a0\00a0menu';
font-size: 0.875rem;
}
p.post-text::first-letter{
text-transform: uppercase;
}
.posted-by {
color: #424242;
font-size: 0.875rem;
}
.posted-by svg {
vertical-align: bottom;
}
// Send a 'GET' request to the specified url and run the callback function when it completes.
function httpGetAsync(url, callback) {
var xmlHttp = new XMLHttpRequest();
xmlHttp.onreadystatechange = function() {
if (xmlHttp.readyState == 4 && xmlHttp.status == 200)
callback(xmlHttp.responseText);
};
xmlHttp.open('GET', url, true);
xmlHttp.send(null);
}
// Get page scroll percentage.
function getScrollPercent() {
return ((document.documentElement.scrollTop||document.body.scrollTop) / ((document.documentElement.scrollHeight||document.body.scrollHeight) - document.documentElement.clientHeight) * 100);
}
/*
Store users in an array to make things easier.
Store posts in an array to make things easier.
Store a reference to #content-area in a variable for quick access.
Store a reference to #users-view-button in a variable for quick access.
Store a reference to #posts-view-button in a variable for quick access.
Store the Random User Generator URI we're using in a variable.
Store the JSON Placeholder URI we're using in a function that auto-increments.
Store the Unsplash it URI we're using in a variable.
*/
var users = [];
var posts = [];
var contentArea = null;
var usersViewButton = null;
var postsViewButton = null;
var usersEndpoint = 'https://randomuser.me/api?seed=%22ph%27nglui%20mglw%27nafh%20Cthulhu%20R%27lyeh%20wgah%27nagl%20fhtagn%22&results=25&nat=US';
var postsEndpointCounter = 1;
function postsEndpoint(){
postsEndpointCounter++;
return 'https://jsonplaceholder.typicode.com/comments?postId='+postsEndpointCounter;
}
var imagesEndpoint = 'https://unsplash.it/800/800?image=';
// Mode variables to help with state management.
var POSTS_VIEW = 0;
var USERS_VIEW = 1;
var currentView = POSTS_VIEW;
// Function closure, used to get the next post id.
var nextPostId = (function(){
var postCounter = 0;
return function () {return postCounter++;}
})();
// Generate a valid random id for an image from the Unsplash It API.
function randomImageId(){
var invalidIds = [86, 97, 105, 138, 148, 150, 205, 207, 224, 226, 245, 246, 262, 285, 286, 298, 303, 332, 333, 346, 359, 394, 414, 422, 438, 462, 470, 489, 561, 578, 589, 595, 597, 624, 632, 636, 644, 647, 673, 697, 706, 707, 708, 709, 710, 711, 712, 713, 714, 725, 734, 745, 746, 747, 748, 749, 750, 751, 752, 753, 754, 759, 761, 762, 763, 771, 801, 812, 843, 850, 854, 895, 897, 917, 920, 956, 963];
var newId = Math.floor(Math.random() * 1000);
while(invalidIds.indexOf(newId) !== -1)
newId = Math.floor(Math.random() * 1000);
return newId;
}
/*
Application entry point / document has been loaded.
Get the #content area stored in its respective variable.
Send a request to the API, process data once the response is received.
*/
document.addEventListener('DOMContentLoaded', function(event) {
contentArea = document.getElementById('content-area');
usersViewButton = document.getElementById('users-view-button');
postsViewButton = document.getElementById('posts-view-button');
usersViewButton.addEventListener('click', function(e){
if (currentView == USERS_VIEW)
return;
currentView = USERS_VIEW;
httpGetAsync(usersEndpoint, getUsers);
});
postsViewButton.addEventListener('click', function(e){
if (currentView == POSTS_VIEW)
return;
currentView = POSTS_VIEW;
posts = [];
httpGetAsync(postsEndpoint(),getPosts);
});
httpGetAsync(usersEndpoint,function(e){
getUsers(e);
httpGetAsync(postsEndpoint(),getPosts);
});
window.addEventListener('scroll', function(e) {
if (getScrollPercent() >= 80 && currentView == POSTS_VIEW) httpGetAsync(postsEndpoint(),getPosts);
});
window.addEventListener('resize', function(e) {
if (getScrollPercent() >= 80 && currentView == POSTS_VIEW) httpGetAsync(postsEndpoint(),getPosts);
});
});
// Store the parsed results to the respective variable and render the users.
function getUsers(data){
users = JSON.parse(data).results;
if(currentView == USERS_VIEW)
renderUsers();
}
// Store the parsed results to the respective variable and render the posts.
function getPosts(data){
var newPosts = JSON.parse(data);
for (var key in newPosts){
posts.push(newPosts[key].body);
}
renderPosts();
}
// Functional component for the mail icon.
function SvgMail(props){
return <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="#424242" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round"><path d="M4 4h16c1.1 0 2 .9 2 2v12c0 1.1-.9 2-2 2H4c-1.1 0-2-.9-2-2V6c0-1.1.9-2 2-2z"></path><polyline points="22,6 12,13 2,6"></polyline></svg>;
}
// Functional component for the calendar icon.
function SvgCalendar(props){
return <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="#424242" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round"><rect x="3" y="4" width="18" height="18" rx="2" ry="2"></rect><line x1="16" y1="2" x2="16" y2="6"></line><line x1="8" y1="2" x2="8" y2="6"></line><line x1="3" y1="10" x2="21" y2="10"></line></svg>;
}
// Functional component for the map pin icon.
function SvgMapPin(props){
return <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="#424242" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round"><path d="M21 10c0 7-9 13-9 13s-9-6-9-13a9 9 0 0 1 18 0z"></path><circle cx="12" cy="10" r="3"></circle></svg>;
}
// Functional component for the user icon.
function SvgUser(props){
return <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="#636363" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round"><path d="M20 21v-2a4 4 0 0 0-4-4H8a4 4 0 0 0-4 4v2"></path><circle cx="12" cy="7" r="4"></circle></svg>;
}
// Functional component for the user card.
function UserCard(props){
var user = props.user;
return <div className="col-md-offset-1 col-lg-offset-2">
<div className="card fluid" id={"user_"+user.login.username}>
<div className="section row">
<div className="col-sm-2 col-md-1">
<img src={user.picture.medium} alt={user.login.username} className="user-image" />
</div>
<div className="col-sm">
<h4 className="user-name">{user.name.title} {user.name.first} {user.name.last}
<small>{user.login.username}</small>
</h4>
</div>
</div>
<div className="section">
<p className="user-email"> <SvgMail /> {user.email}</p>
</div>
<div className="section">
<p className="user-birth"> <SvgCalendar /> {user.dob.split(" ")[0].split("-").reverse().join("/")}</p>
</div>
<div className="section">
<p className="user-location"> <SvgMapPin /> {user.location.city}, {user.location.state}</p>
</div>
</div>
</div>;
}
// Functional component for the post card.
function PostCard(props){
return <div className="col-md-offset-1 col-lg-offset-2">
<div className="card fluid" id={"post_"+nextPostId()}>
<img className="section media" src={props.image} alt="post image"/>
<div className="section">
<p className="post-text">{props.text+'.'}</p>
</div>
<div className="section">
<p className="posted-by"> <SvgUser /> Posted by {users[props.userId].login.username}</p>
</div>
</div>
</div>;
}
// Renders a list of users as cards.
function renderUsers(){
var userCards = users.map(
function(user, key){
return <UserCard user={user} key={key}/>;
}
);
ReactDOM.render(
<div>{userCards}</div>
,contentArea);
}
// Render a list of posts as cards.
function renderPosts(){
var postCards = posts.map(
function(post, key){
return <PostCard text={post} userId={Math.floor(Math.random() * 25)} image={imagesEndpoint+randomImageId()} key={key}/>;
}
);
ReactDOM.render(
<div>{postCards}</div>
,contentArea);
}
Also see: Tab Triggers