How to Create a WordPress Functionality Plugin

WordPress plugins are crucial when designing any WordPress website. They are used to adding extra functionality to a WordPress website. Some functionalities are either too basic or too customized for there to be a plugin for it. <!--more--> Therefore, it may be challenging to find a plugin that meets your needs.

This article will walk you through WordPress functionality plugins and how to create one.

Table of contents #

• An overview of WordPress plugins
• How WordPress plugins work
• WordPress plugin development
• Step 1: Requirements definition
• Step 2: Navigate to WordPress plugins folder and create your plugin file
• Step 3: Create the main PHP file for your plugin
• Step 4: Set up your plugin to add functions
• Functionality plugin

Prerequisites #

To create and run a plugin on your WordPress website, you will need:

• A comprehensive understanding of WordPress, HTML, CSS, JavaScript, and PHP.
• A text editor.
• WordPress installed on your computer.

An overview of WordPress plugins #

Plugins are tools that you install to add features and functionality to your WordPress website. A default WordPress installation is like a computer with no applications.

With WordPress, plugins are like those extra applications you install to do different tasks.

Customizing a WordPress website may not be enough. You may need to add more functionality for it to meet your requirements. That is where plugins come in.

In this tutorial, we will create a functionality plugin that will display a link inside the footer of our website. The link will show up on every page.

The link will direct you to another page for a service that may satisfy your needs.

WordPress has plugins such as Yoast, which helps your site rank high in search engines, WooCommerce which helps you set up an online store, and others that allow you to improve your site's performance.

To use plugins, you can either build and import them, or install them directly on your website. Do not install plugins from sources you do not trust. You can trust plugins available on wordpress.org.

Also, make sure the plugin you install does an excellent job and matches your website's needs.

How WordPress plugins work #

A WordPress plugin works by integrating and running a set of functions on the WordPress software. WordPress is programmed in a way that allows developers to add their own code to it. In simpler terms, WordPress is written in a way that allows it to be extended using plugins.

Plugins add extra code to your WordPress website, thus making it more functional. As a result, it enables you to customize your website as per your need. Unfortunately, adding a plugin to your site is heavier than you may think.

Data in WordPress is stored in the WordPress database. Each plugin installed on a WordPress website is installed in your WordPress database. Therefore, you can activate and deactivate the plugins at any time.

Once you access the website, WordPress connects to the database, loads the main software, and loads the active plugins. After that, the code runs and gets processed on your server, and then sent to the browser.

WordPress plugin development #

WordPress' main files override when it is updated. Therefore, if a custom functionality is added to the original WordPress code directly, your changes are wiped out upon WordPress update.

That is why plugins are essential. Thus, adding any feature and functionality should be done using plugins.

Let us go through the steps of creating a WordPress functionality plugin.

Step 1: Requirements definition #

The first step of creating a functional WordPress plugin is to define the requirements. Make sure you have a clear idea of the objective of the plugin. Also, the issue the plugin will solve.

Consider what the features and functionalities of the plugin are.

When you gather all the requirements, you can move to the second step of plugin development. In our case, we will create a plugin that will display a fixed link on the footer of our website.

Step 2: Navigate to WordPress plugins folder and create your plugin file #

To create a WordPress plugin directory structure, first, navigate to the default WP directory for storing the plugin code. On your text editor, head to the wp-contents/plugins/ folder of your WordPress directory.

In our case, we will use Visual Studio Code editor. Create a new folder and name it using the plugin's name; separate the words using hyphens, such as functionality-plugin.

The next step is to create a PHP file inside the folder functionality-plugin.php as shown below:

Step 3: Create the main PHP file for your plugin #

Before adding code that adds functionality to your plugin file, it is vital to provide the information of the plugin you are developing. WordPress wants all the plugins to follow its standards.

The information below is about the plugin we are developing:

/*
* Plugin Name: Functionality Plugin
* Description: This plugin will display a fixed link on the footer of your website.
* Version: 1.0.0
* Author: Your Name or Your Company
* Author URI: http://yourdomain.com
* License: GPL2
*/

Save the PHP file, then navigate to your WP dashboard and click on Plugins; located on the left panel. You will see your plugin listed there.

Step 4: Set up your plugin to add functions #

Our plugin is empty. Therefore, it can not add any functionality to a website.

The next step is setting up the plugin code and adding functions. This is the step where you bring the idea to life.

We will use CSS to style the plugin and JavaScript to implement the functionality. JavaScript displays an alert if the code is well executed.

First, to make the button appear, we need a function. We also need to hook this function into an action hook. Action hooks add or override the core functionality of WordPress.

We will use the functionality-plugin.php file to add the plugin's functionality and the complete code will be as shown below:

//include CSS and JS
function dl_enqueue_assets () {
    wp_enqueue_style( 'functionality-styles', plugin_dir_url( __FILE__ ) . 'styling/style.css' );
    wp_enqueue_script( 'functionality-scripts', plugin_dir_url( __FILE__ ) . 'styling/script.js', array('jquery') );
}
add_action ("wp_enqueue_scripts", "dl_enqueue_assets");

// action fixed button
function dl_fixed_button (){
    ?>
    <a href="#" class="dl_fixed_button">Click Here!</a>
<?php
}
add_action ("wp_footer","dl_fixed_button");

In the code above, we have created a new folder inside functionality-plugin folder and named it styling. Inside styling folder, we have created the style.css and the script.js files that style and add functionality to the plugin, respectively.

In our main plugin code, we included the style.css and script.js files. Below is the CSS and JavaScript code you will include in your PHP file.

style.css

.dl_fixed_button {
	display: inline-block;
	background: #fd63dc;
	color: #fff;
	padding: 5px 10px;
	font-size: 12px;
	font-weight: bold;
	position: fixed;
	z-index: 100;
	bottom: 20px;
	left: 20px;
	text-decoration: none;
}

script.js

 jQuery (function($){
   $ ('.dl_fixed_button').click(function(){
       alert('A good click!');
   });
 });

This is how the plugin works in a WordPress website:

You can download the source code from here.

Functionality plugin #

Hopefully, if you have made it this far, we agree that developing a WordPress plugin is relatively easy. However, if you are creating a plugin, I suggest you familiarize yourself with how actions and filters work.

Coding WP plugins help you gain a more profound knowledge of how WordPress works. Furthermore, you can freely share your plugin with others via the WordPress plugin directory.

Conclusion #

Congratulations! You developed a WordPress plugin. We have created a plugin that displays a fixed link inside the website's footer and shows up on every page.

Following and putting this tutorial into practice enables you to build plugins, thus expanding your WordPress website's functionality.

Happy coding!

---

Peer Review Contributions by: Monica Masae