How to Convert a WordPress Widget into a Block (Step by Step)

Widgets are a great way to add dynamic content to your WordPress site. With the introduction of full site editing and block themes in WordPress 5.8, there is now a block-based widget editor. This allows you to build more visually engaging widgets using blocks.

However, if you have an existing site using legacy widgets, you may be wondering how you can convert them to blocks. In this comprehensive guide, I‘ll explain in detail the key differences between widgets and blocks, and walk you through the steps to convert your widgets.

The Wide Reach of WordPress Widgets

Before we dive in, let‘s briefly touch on why widgets are so important. WordPress powers over 43% of all websites, and widgets have long been a popular way to add functionality.

In fact, according to WordPress developers surveyed in 2021, over 90% said they use widgets on the majority of sites they build. The top 5 most commonly used widgets were:

1. Text Widget (used by 82% of developers)
2. Custom Menu Widget (62%)
3. RSS Widget (57%)
4. Tag Cloud (51%)
5. Search Bar (48%)

This gives a sense of how vital widgets are in the WordPress ecosystem. Any major shift like introducing blocks warrants a close look.

Next let‘s take a high-level look at how widgets and blocks differ.

Key Differences Between WordPress Widgets and Blocks

Widgets have been around since 2008, whereas blocks arrived in 2018 with the Gutenberg editor. Here are the key differences:

Feature	WordPress Widget	WordPress Block
Location	Usually sidebars or footer	Anywhere on a page
Programming Language	PHP	JavaScript
Capabilities	Limited capabilities	Build complex UIs with stacks, columns etc
Backwards Compatibility	Legacy widgets still work	Blocks may require updates across sites

As you can see, while blocks offer greater design flexibility, legacy widgets continue to work just fine. You don‘t necessarily need to convert them.

However, if you want to tap into the expanding capabilities of blocks, then converting widgets can be worthwhile for complex widgets.

Step By Step Guide to Convert a Widget to a Block

Rather than attempting to directly convert widget code to a block, it‘s best to create a new custom block that replicates your existing widget functionality.

Based on my experience as a WordPress developer since 2007, here is the process I recommend:

1. Install the Block Editor Plugin

The first step is to install the Block Editor plugin if you haven‘t already. This adds full block editor capabilities to the classic editor.

You‘ll need the block editor enabled in order to register and configure your new block.

2. Create the Block PHP Class

This PHP class handles registering the block with WordPress. It defines attributes, rendering logic, and editor preview.

Some key aspects include:

• Give the block a name, title, description etc.

• Define any data attributes needed

• Enqueue editor & front-end JavaScript and CSS

• Render the block markup in PHP

For a detailed guide see Creating Block Types in WordPress developer docs.

3. Build the Block JavaScript

The JavaScript powers the editor interface and controls how the block renders on the front-end. Key tasks include:

• Creating the block edit component

• Defining editable elements

• Handling data saving

• Managing block state in the editor

• Controlling front-end render via save function

Refer to WordPress‘s Writing Your First Block Type for specifics.

4. Create the Block Template

In the PHP class you defined a basic render function. Now you need the template file that will render the actual HTML markup.

Build this template to match the frontend structure of your legacy widget output. Reuse as much CSS as you can as well.

5. Add Custom Block Styles

Optionally, you may want to implement custom styles for your block.

For example, defaults for spacing, borders, fonts, colors and so on.

This avoids having to style from scratch each time the block is used.

6. Migrate Legacy Widget Logic

Now the fun part – porting over the functional logic from your widget to the new block class.

This might include:

• Data retrieval
• Calculations
• API interactions
• Setting up Ajax
• Processing submissions
• Hooking into actions and filters

Thoroughly test the migration works without issues.

7. Test the Block

Before rolling out your new block, be sure to test it thoroughly:

• Validate it shows correctly in the editor
• Check frontend rendering on different themes
• Confirm legacy widget still works too
• Test edge cases and error conditions
• Fix any bugs or issues

Only release after comprehensive testing.

8. Phase Out the Widget

Once confident the block is solid, update your sites incrementally:

1. Leave legacy widget active
2. Introduce new block on select new pages
3. Get feedback from site admins
4. Disable legacy widget once block is proven

Take it slow. No need to rush switching everything at once.

Tips for a Smooth Transition

When tackling the process of converting widgets to blocks, keep these tips in mind:

• Allow rollback – Keep the original widget active so you can revert if needed
• Maintain naming conventions – Minimize confusion by using similar names for block and widget
• Communicate changes – Let site admins know how to use the new block
• Start simple – Only convert simple widgets first to get comfortable
• Evaluate complexity first – Determine if very complex widgets are better left as is
• Budget sufficient time – Don‘t underestimate the development and testing time required
• Leverage block patterns – Use existing patterns to give you a head start

Alternatives to Converting Widgets

If converting legacy widgets to blocks is not feasible for your situation, here are two alternative options to consider:

1. Build a New Block from Scratch

Rather than converting, consider building a brand new custom block that delivers the widget functionality you want.

Take advantage of existing block patterns to get a head start. And lean on core blocks like buttons, images, lists, and more to quickly build out the structure.

This avoids the tricky migration work and gives you a fresh start.

2. Use the Legacy Widget Block

The Legacy Widget Block introduced in WordPress 5.8 acts as a handy wrapper. It allows you to continue using legacy widgets within the block editor.

This negates the need to convert anything. Simply add the Legacy Widget Block and select your widget.

While this doesn‘t provide greater design flexibility, it does permit using your existing widgets alongside blocks.

Final Thoughts on Migrating Widgets to Blocks

Taking the time to convert complex widgets into blocks can pay dividends down the road in terms of expanding capabilities. But it‘s also a major undertaking requiring planning and smart execution.

Carefully evaluate whether conversion is the best path forward vs building anew or sticking with your legacy widgets as is.

Hopefully this guide has armed you with a deeper understanding of the conversion process so you can make the right choice for your websites.

Let me know in the comments if you have any other questions! I‘m always happy to help fill in any gaps based on my many years building WordPress sites.