JavaScript Image Gallery with Thumbnails

JavaScript Image Gallery with Thumbnails
Code Snippet:JS Thumbnail Gallery
Author: Donal Donohoe
Published: April 8, 2024
Last Updated: April 8, 2024
Downloads: 65
License: MIT
Edit Code online: View on CodePen
Read More

This JavaScript code snippet helps you to create an image gallery with thumbnails. It allows you to view and navigate through multiple images easily. By clicking on thumbnails or using arrow keys, you can switch between images. This code simplifies showcasing images in a visually appealing manner.

You can use this code on your website to showcase image collections attractively. It enhances user experience by providing a convenient way to navigate through images. This gallery with thumbnails improves engagement and helps display visuals effectively.

How to Create JavaScript Image Gallery with Thumbnails

1. Begin by setting up your HTML file. Inside the <body> tag, create a <div> with the class “gallery” where your image gallery will be placed.

<div class="gallery">
  <img src="https://source.unsplash.com/640x360/?girl" />
  <img src="https://source.unsplash.com/640x360/?mountain" />
  <img src="https://source.unsplash.com/640x360/?rose" />
  <img src="https://source.unsplash.com/640x360/?bee" />
  <img src="https://source.unsplash.com/640x360/?forest" />
  <img src="https://source.unsplash.com/640x360/?beauty" />
  <img src="https://source.unsplash.com/640x360/?rose" />
  <img src="https://source.unsplash.com/640x360/?car" />
  <img src="https://source.unsplash.com/640x360/?cute" />
  <img src="https://source.unsplash.com/640x360/?butterfly" />
</div>

2. Add the CSS code to style your image gallery. This code provides the layout and appearance for your gallery, including the main image display and thumbnail navigation.

body {
background: #eee;
}
.gallery {
	position: absolute;
	top: 50%;
	left: 50%;
	padding: 20px;
	max-width: 90%;
	-webkit-transform: translateX(-50%) translateY(-50%);
	-moz-transform: translateX(-50%) translateY(-50%);
	transform: translateX(-50%) translateY(-50%);
	border: 1px solid #777;
	overflow: hidden;
}
.gallery .inner {
	position: relative;
	overflow: hidden;
	display: block;
	width: auto;
	max-width: 800px;
}
.gallery img {
	display: none;
}
.main {
	position: relative;
	width: 100%;
	height: 500px;
	overflow: hidden;
	background: #ccc;
	background-repeat: no-repeat;
	background-position: center center;
	background-size: cover;
	overflow: hidden;
	margin-bottom: 20px;
}
.main:before {
content: "";
position: absolute;
left: 0;
bottom: 0;
width: 100%;
height: 100px;

background: -moz-linear-gradient(top,  rgba(0,0,0,0) 0%, rgba(0,0,0,0.7) 100%);
background: -webkit-linear-gradient(top,  rgba(0,0,0,0) 0%,rgba(0,0,0,0.7) 100%);
background: linear-gradient(to bottom,  rgba(0,0,0,0) 0%,rgba(0,0,0,0.7) 100%);
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#00000000', endColorstr='#a6000000',GradientType=0 );
}
.main-selected {
	animation: crossfade 0.5s ease;
	-webkit-animation: crossfade 0.5s ease;
	-moz-animation: crossfade 0.5s ease;
}
@keyframes crossfade {
	0% { opacity: 0.7; }
	100% { opacity: 1; }
}

@-webkit-keyframes crossfade {
	0% { opacity: 0.7; }
	100% { opacity: 1; }
}

@-moz-keyframes crossfade {
	0% { opacity: 0.7; }
	100% { opacity: 1; }
}
.main span {
	position: absolute;
	display: block;
	text-align: center;
	font-size: 16px;
	font-family: sans-serif;
	color: #fff;
	bottom: 10px;
	left: 0;
	right: 0;
}
.thumb-roll {
position: relative;
width: auto;
overflow-x: auto;
overflow-y: hidden;	

white-space: nowrap;
}
.thumb {
	display: inline-block;
	position: relative;
	width: 100px;
	height: 100px;
	margin-right: 20px;
	background: #ccc;
	overflow: hidden;
	background-repeat: no-repeat;
	background-position: center center;
	background-size: cover;
	overflow: hidden;
	cursor: pointer;
}
.thumb:last-of-type {
	margin-right: 0px;
}
.thumb:after {
	content: "";
	position: absolute;
	width: 100%;
	height: 100%;
	box-shadow: inset 5px 5px 0px rgba(51, 204, 255, 0), inset -5px -5px 0px rgba(51, 204, 255, 0);
}
.thumb.current:after {
	box-shadow: inset 5px 5px 0px rgba(51, 204, 255, 1), inset -5px -5px 0px rgba(51, 204, 255, 1);
	background: rgba(255,255,255,0.4);
	cursor: default;
}
.thumb:hover:after {
	box-shadow: inset 5px 5px 0px rgba(51, 204, 255, 1), inset -5px -5px 0px rgba(51, 204, 255, 1);
}

3. Now, make sure to include the necessary CDN link for jQuery.

<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js'></script>

4. Finally, add the JavaScript code that will create the image gallery functionality. This code dynamically generates the gallery, including thumbnails and navigation features.

// Fit inner div to gallery
$('<div />', { 'class': 'inner'  }).appendTo('.gallery');

// Create main image block and apply first img to it
var imageSrc1 = $('.gallery').children('img').eq(0).attr('src');
$('<div />', { 'class': 'main'  }).appendTo('.gallery .inner').css('background-image', 'url(' + imageSrc1 + ')');

// Create image number label
var noOfImages = $('.gallery').children('img').length;
$('<span />').appendTo('.gallery .inner .main').html('Image 1 of ' + noOfImages);

// Create thumb roll
$('<div />', { 'class': 'thumb-roll'  }).appendTo('.gallery .inner');

// Create thumbail block for each image inside thumb-roll
$('.gallery').children('img').each( function() {
	var imageSrc = $(this).attr('src');
	$('<div />', { 'class': 'thumb'  }).appendTo('.gallery .inner .thumb-roll').css('background-image', 'url(' + imageSrc + ')');
});

// Make first thumbnail selected by default
$('.thumb').eq(0).addClass('current');

// Select thumbnail function
$('.thumb').click(function() {
	
	// Make clicked thumbnail selected
	$('.thumb').removeClass('current');
	$(this).addClass('current');
	
	// Apply chosen image to main
	var imageSrc = $(this).css('background-image');
	$('.main').css('background-image', imageSrc);
	$('.main').addClass('main-selected');
	setTimeout(function() {
		$('.main').removeClass('main-selected');
	}, 500);
	
	// Change text to show current image number
	var imageIndex = $(this).index();
	$('.gallery .inner .main span').html('Image ' + (imageIndex + 1) + ' of ' + noOfImages);
});

// Arrow key control function
$(document).keyup(function(e) {

  // If right arrow
  if (e.keyCode === 39) {

	// Mark current thumbnail
	var currentThumb = $('.thumb.current');
	var currentThumbIndex = currentThumb.index();
	if ( (currentThumbIndex+1) >= noOfImages) { // if on last image
		nextThumbIndex = 0; // ...loop back to first image
	} else {
		nextThumbIndex = currentThumbIndex+1;
	}
	var nextThumb = $('.thumb').eq(nextThumbIndex);
	currentThumb.removeClass('current');
	nextThumb.addClass('current');
	
	// Switch main image
	var imageSrc = nextThumb.css('background-image');
	$('.main').css('background-image', imageSrc);
	$('.main').addClass('main-selected');
	setTimeout(function() {
		$('.main').removeClass('main-selected');
	}, 500);
	
	// Change text to show current image number
	$('.gallery .inner .main span').html('Image ' + (nextThumbIndex+1) + ' of ' + noOfImages);
	
  }
  
  // If left arrow
  if (e.keyCode === 37) { 

	// Mark current thumbnail
	var currentThumb = $('.thumb.current');
	var currentThumbIndex = currentThumb.index();
	if ( currentThumbIndex == 0) { // if on first image
		prevThumbIndex = noOfImages-1; // ...loop back to last image
	} else {
		prevThumbIndex = currentThumbIndex-1;
	}
	var prevThumb = $('.thumb').eq(prevThumbIndex);
	currentThumb.removeClass('current');
	prevThumb.addClass('current');
	
	// Switch main image
	var imageSrc = prevThumb.css('background-image');
	$('.main').css('background-image', imageSrc);
	$('.main').addClass('main-selected');
	setTimeout(function() {
		$('.main').removeClass('main-selected');
	}, 500);
	
	// Change text to show current image number
	$('.gallery .inner .main span').html('Image ' + (prevThumbIndex+1) + ' of ' + noOfImages);
	
  }
    
});

That’s all! hopefully, you have successfully created image gallery with thumbnails on your website. If you have any questions or suggestions, feel free to comment below.

Leave a Comment