How to Build an Image Gallery Plugin for WordPress
Posted on 18th June 2023
Building an image gallery plugin for WordPress is a great way to improve the functionality of your website. Not only will it allow you to display images in a more organized manner, but it will also provide your visitors with a way to navigate through your images more easily. In this article, we will show you how to build an image gallery plugin for WordPress.
Getting Started
The first thing you need to do is to create a new folder for your plugin. You can name it anything you want. For this example, we will name it “my-gallery”.
Next, you need to create a file inside this folder. The file should be named “my-gallery.php”. This file will contain the code for your plugin.
Once you have created the file, you need to open it in a text editor and add the following code:
This code defines the plugin and sets up a basic structure for it. Next, we need to write the code for displaying the gallery.
Displaying the Gallery
The gallery will be displayed in a grid. To do this, we will use the “columns” and “rows” CSS properties.
First, we need to add some CSS to our plugin. We will do this by adding the following code to our “my-gallery.php” file:
This code adds a new CSS file to our plugin. Next, we need to create this CSS file. We will name it “my-gallery.css” and save it in the “my-gallery” folder.
The CSS code for our gallery is as follows:
.my-gallery {
columns: 4;
rows: 2;
}
.my-gallery img {
width: 100%;
}
This code will create a grid with 4 columns and 2 rows. The images will be displayed in these columns and rows.
Next, we need to add the HTML code for our gallery. We will do this by adding the following code to our “my-gallery.php” file:
<?php
// Exit if accessed directly
if ( !defined( 'ABSPATH' ) ) exit;
// if ( !class_exists( 'My_Gallery' ) ):
// class My_Gallery {
// function my_gallery_css() {
// wp_enqueue_style( 'my-gallery', plugins_url( 'my-gallery/my-gallery.css' ) );
// }
// add_action( 'wp_enqueue_scripts', 'my_gallery_css' );
// function my_gallery_html() {
// echo '
// echo ‘
‘;// echo ‘
‘;// echo ‘
‘;// echo ‘
‘;// echo ‘
‘;// echo ‘
‘;// echo ‘
‘;
// }
// add_action( ‘wp_footer’, ‘my_gallery_html’ );
// }
// endif;
?>
This code will add the HTML code for our gallery to the “wp_footer” action hook. This hook is used to output code in the footer of the WordPress website.
The HTML code for our gallery is as follows:
This code will output a grid with 6 images. The images will be displayed in the order that they are added to the code.
Adding the Images
The images for our gallery can be added to the “my-gallery” folder. You can name the images anything you want.
Once you have added the images to the folder, you need to update the “src” attribute of the “” tags in the HTML code. The “src” attribute should point to the location of the image.
Conclusion
In this article, we have shown you how to build an image gallery plugin for WordPress. You can use this plugin to display images in a grid on your WordPress website.
Assuming you have a basic understanding of PHP and WordPress development, let’s look at how to build a simple image gallery plugin for WordPress.
First, you’ll need to create a new folder for your plugin. We’ll call ours “my-gallery”.
Next, inside your new “my-gallery” folder, create a new file called “my-gallery.php”. This will be the main plugin file.
Now, open “my-gallery.php” in your text editor and let’s get started.
The first thing we need to do is tell WordPress that this is a plugin. We do this by adding a PHP comment at the top of the file with some basic information about the plugin:
This information is used by WordPress to display your plugin in the “Plugins” admin screen.
Next, we need to actually write the code for our plugin. For this example, we’ll keep it simple and just create a shortcode that outputs a gallery of images.
First, we’ll register the shortcode with WordPress:
This tells WordPress that whenever it sees the [my_gallery] shortcode, it should run the my_gallery_shortcode() function. We’ll write that function next:
All we’ve done so far is register the shortcode and create an empty function for it. Now we need to actually write the code to output the gallery.
For this example, we’ll assume that the images are stored in a folder called “gallery” inside the plugin folder.
First, we need to get a list of all the images in the gallery folder. We can do this with the WordPress function scandir():
This gives us an array of all the files in the gallery folder. Note that we’re using the WordPress function plugin_dir_path() to get the path to the plugin folder. This is important because it ensures that the path will be correct even if the plugin is installed in a different location.
Next, we need to loop through the array of images and output the HTML for each one:
<?php
/**
* Plugin Name: My Gallery
* Plugin URI: https://example.com/my-gallery
* Description: A simple image gallery plugin for WordPress
* Version: 1.0
* Author: John Doe
* Author URI: https://example.com
* License: GPL2
*/
// Register the shortcode
add_shortcode( 'my_gallery', 'my_gallery_shortcode' );
// Shortcode function
function my_gallery_shortcode() {
// Get a list of all the images in the gallery folder
$images = scandir( plugin_dir_path( __FILE__ ) . 'gallery' );
// Loop through the images
foreach ( $images as $image ) {
// Ignore the . and .. folders
if ( $image != '.' && $image != '..' ) {
// Output the HTML for each image
echo '‘;
}
}
}
// This is where we’ll write the rest of our plugin code
?>
This code loops through the array of images and outputs the HTML for each one. Note that we’re using the WordPress function plugins_url() to get the URL for each image. This is important because it ensures that the URL will be correct even if the plugin is installed in a different location.
That’s all there is to it! This is a very basic example, but it should give you a good starting point for building your own image gallery plugin.
