Develop Custom WordPress Widgets

Posted in WordPress by Erin Myers

Last updated on February 1st, 2022

You’ve likely used widgets in WordPress, as handy ways to customize certain areas on your website. Sometimes they do exactly what you need, but occasionally you might want them to have a slightly different appearance or functionality.

Fortunately, developing custom widgets for WordPress is possible. These PHP objects can be created from scratch and implemented on your site, or collected into a plugin for use in multiple themes. Either way, creating your own widgets is not as hard as you might expect.

In this article, we’ll go over how to develop your own custom widgets, and walk through determining what your widget will be used for and what you’ll need first. Let’s get started!

Determine What Your Widget Is For

There are a few things you’ll need to think about before you start putting together your first custom widget. Planning ahead will help you create your niche piece of coding more effectively.

Widgets can only be placed in widget-ready areas of a WordPress website. So you’ll want to make sure you know exactly where your widget will be implemented, and what its purpose will be. You should be able to pinpoint what will make your widget unique, as this will help you to better plan out its design.

Depending on the theme you are using, widgets can usually be placed in sidebars, headers, and footers:

Sometimes there are multiple options for one or more of these areas (such as a “Sidebar 1” and “Sidebar 2”, for example). No matter where it’s placed, a widget essentially uses PHP object programming to produce a piece of HTML for front-end display and back-end administration.

As you will be adjusting the WP_Widget class on your site in order to make custom changes, you’ll want to finalize the plan for your widget prior to diving in. If there are other elements to your widget, such as a contact form function or a feed of data, make sure you have all the extra information you require before starting.

What Will I Need? Start With the Base Code for a Widget

There are two main ways to approach developing your custom widget. You can create a plugin that your widget will be located in, or you can paste your widget code directly into your functions.php file.

When you choose the latter option, your widget will only be functional with your current theme. Therefore, in most cases the best choice is to use a custom plugin, which will enable you to use the widget with any theme.

You will also need a WordPress widget’s base code, a text editor for editing your code, access to your WordPress admin dashboard, and a Secure File Transfer Protocol (SFTP) client for accessing your site’s files directly. Once you have all the necessary ingredients in place, you’re ready to make a widget.

How to Start Building Your Custom WordPress Widget (In 3 Steps)

Once you decide what the purpose and function of your widget is going to be, you can begin to develop the code. You’ll want to be familiar with the basics of classes and objects in PHP5, as well as the anatomy of a widget.

To get started, you’ll want to set up a new folder to hold your widget files. Place your new folder in your wp-content/plugins/ directory, and name it:

Now you have a staging area for your new widget’s code files.

Step 1: Use a Base Code to Format Your Widget

While you can work from scratch if you’d like, the easiest way to get started is to use a well-written base code. You can find the WP_Widget class in your WordPress site’s file directory, located in wp-includes/class-wp-widget.php.

To create your custom widget, you’ll be extending the existing class to execute new functions. You can also find widget base codes on GitHub. While there are many programmers out there willing to share their code, be sure to review what you’re using and make sure it meets the WordPress coding standards.

Once you have your base code, you’ll need to insert it into the file you just created, so that WordPress will register your widget:

// register My_Widget
add_action( 'widgets_init', function(){
 register_widget( 'My_Widget' );
});

The registration code is simple, and should be copied directly into your widget’s file.

Step 2: Customize Your Widget

At this point, you can start customizing your widget to do whatever you’d like. Naturally, the way you do this will vary depending on your goals. However, there are a few basics you will need to familiarize yourself with first, especially if you’re new to development.

One concept you’ll want to understand are WordPress hooks. These enable you to ‘hook in’ to WordPress’ core code, and enact a certain function at a specific point in time.

There are four main elements in the widget class that you’ll need to work with. They include:

Construct: This sets up what your widget will look like in the administration panel.
Widget: This will process your functions and display the HTML code on the front end of your site.
Form: This is where you set up form fields, for retrieving option values from your widget’s database in the administration panel.
Update: This is how your widget options get saved to the database.

Even if your widget doesn’t use form fields or have options that need to be updated to the database, it’s still good programming practice to include the placeholder code for each element in your widget’s structure.

Step 3: Turn Your Widget into a Custom Plugin

Once you have crafted the specifics of your widget, you’ll want to make sure you can use it like a plugin. To do that, you’ll need to include a header code that tells WordPress how to treat this new piece of code.

At the very top of your widget’s file, you can place the following code:

<?php
/*
Plugin Name: New-Widget
Plugin URI: http://wordpress.org/extend/plugins/#
Description: This is an example plugin 
Author: Your Name
Version: 1.0
Author URI: http://example.com/
*/

After you add this code, save the file and upload the changes to your site. You’ll now be able to go into your WordPress dashboard and find your plugin in the Plugins menu:

At this point, you can activate the plugin. Then, you’ll be able to access its settings in the Appearance > Widgets menu in WordPress. All that’s left is to start using your newly-modified widget!

Build Customized Digital Experiences on WP Engine

When you encounter a widget that’s almost perfect, and you wish you could change it, you can use steps we’ve covered here to customize your own WordPress widgets. Plus, you can employ this method to create new widgets with unique functionality quickly.

Here at WP Engine, we have the resources to help you build top-notch WordPress plugins and widgets. We also have lots of options when it comes to fast WordPress hosting and secure hosting plans, so you never have to worry about your site’s performance!