Enqueuing styles and scripts in Wordpress - Mini Project: Build & Apply

Enqueuing Styles and Scripts in WordPress

📖 Scenario: You are building a WordPress theme. To make your theme look good and work well, you need to add CSS styles and JavaScript scripts properly.WordPress has a special way to add these files called enqueueing. This helps avoid conflicts and loads files in the right order.

🎯 Goal: Learn how to enqueue a CSS style and a JavaScript script in your WordPress theme using the correct WordPress functions.

📋 What You'll Learn

Create a function to enqueue styles and scripts

Use wp_enqueue_style to add a CSS file

Use wp_enqueue_script to add a JavaScript file

Hook the function to wp_enqueue_scripts action

💡 Why This Matters

🌍 Real World

Properly adding CSS and JavaScript files is essential for WordPress themes and plugins to work well and avoid conflicts.

💼 Career

WordPress developers must know how to enqueue assets correctly to build professional, maintainable themes and plugins.

1

Create the enqueue function

Create a function called mytheme_enqueue_assets that will hold the code to add styles and scripts.

Wordpress

# Create a function called mytheme_enqueue_assets
# Your code here

Hint

Use the function keyword followed by the function name mytheme_enqueue_assets and parentheses.

2

Enqueue the main stylesheet

Inside the mytheme_enqueue_assets function, use wp_enqueue_style to add a CSS file named style.css located in your theme folder. Use the handle mytheme-style.

Wordpress

function mytheme_enqueue_assets() {
    # Use wp_enqueue_style to add style.css with handle mytheme-style
    # Your code here
}

Hint

Use get_stylesheet_uri() to get the URL of style.css in your theme.

3

Enqueue a JavaScript file

Still inside the mytheme_enqueue_assets function, use wp_enqueue_script to add a JavaScript file named script.js located in the js folder of your theme. Use the handle mytheme-script. Make sure to load the script in the footer by setting the last parameter to true.

Wordpress

function mytheme_enqueue_assets() {
    wp_enqueue_style('mytheme-style', get_stylesheet_uri());
    # Use wp_enqueue_script to add js/script.js with handle mytheme-script and load in footer
    # Your code here
}

Hint

Use get_template_directory_uri() to get the theme folder URL and add /js/script.js to it.

Set dependencies to an empty array array(), version to false, and load in footer true.

4

Hook the function to enqueue scripts and styles

Add an action hook to call mytheme_enqueue_assets on the wp_enqueue_scripts action.

Wordpress

function mytheme_enqueue_assets() {
    wp_enqueue_style('mytheme-style', get_stylesheet_uri());
    wp_enqueue_script('mytheme-script', get_template_directory_uri() . '/js/script.js', array(), false, true);
}

# Hook the function to wp_enqueue_scripts
# Your code here

Hint

Use add_action with the first argument 'wp_enqueue_scripts' and the second argument 'mytheme_enqueue_assets'.

Practice

1. What is the main purpose of using wp_enqueue_style and wp_enqueue_script in WordPress?

easy

A. To remove styles and scripts from WordPress pages

B. To directly print CSS and JavaScript code inside HTML files

C. To safely add CSS and JavaScript files to a WordPress theme or plugin

D. To create new CSS and JavaScript files automatically

Solution

1. Step 1: Understand the function purpose

   wp_enqueue_style and wp_enqueue_script are designed to add CSS and JS files safely to WordPress pages.

2. Step 2: Compare options

   Options B, C, and D describe incorrect uses: printing code directly, removing files, or creating files automatically, which these functions do not do.

3. Final Answer:

   To safely add CSS and JavaScript files to a WordPress theme or plugin -> Option C

4. Quick Check:

   Enqueuing = Safe adding of styles/scripts [OK]

Hint: Enqueue means safely add files, not print or remove [OK]

Common Mistakes:

• Thinking enqueue prints code directly
• Confusing enqueue with file creation
• Using enqueue to remove scripts

2. Which of the following is the correct way to enqueue a CSS file named style.css located in your theme folder?

easy

A. wp_enqueue_script('my-style', get_stylesheet_directory() . '/style.css');

B. wp_enqueue_style('my-style', get_template_directory_uri() . '/style.css');

C. enqueue_style('my-style', '/style.css');

D. wp_add_style('my-style', get_template_directory_uri() . '/style.css');

Solution

1. Step 1: Identify correct function and parameters

   The correct function to enqueue CSS is wp_enqueue_style. The URL should be built with get_template_directory_uri() plus the file path.

2. Step 2: Check each option

   wp_enqueue_style('my-style', get_template_directory_uri() . '/style.css'); uses the correct function and URL. enqueue_style('my-style', '/style.css'); uses a wrong function name. wp_enqueue_script('my-style', get_stylesheet_directory() . '/style.css'); uses wp_enqueue_script which is for JS, not CSS. wp_add_style('my-style', get_template_directory_uri() . '/style.css'); uses a non-existent function wp_add_style.

3. Final Answer:

   wp_enqueue_style('my-style', get_template_directory_uri() . '/style.css'); -> Option B

4. Quick Check:

   Correct function and URL = wp_enqueue_style('my-style', get_template_directory_uri() . '/style.css'); [OK]

Hint: Use wp_enqueue_style with get_template_directory_uri() for theme CSS [OK]

Common Mistakes:

• Using wp_enqueue_script for CSS files
• Wrong function names like enqueue_style
• Using get_stylesheet_directory() without URI

3. What will happen if you run this code in your theme's functions.php?

function load_custom_scripts() {
  wp_enqueue_script('custom-js', get_template_directory_uri() . '/js/custom.js', array('jquery'), '1.0', true);
}
add_action('wp_enqueue_scripts', 'load_custom_scripts');

medium

A. The custom.js script will be loaded in the footer after jQuery

B. The custom.js script will load in the header before jQuery

C. The script will not load because of a missing hook

D. The script will load but without jQuery dependency

Solution

1. Step 1: Analyze the enqueue parameters

   The function enqueues 'custom-js' with dependency on 'jquery', version '1.0', and last parameter true means load in footer.

2. Step 2: Understand the hook and dependencies

   The function is hooked to 'wp_enqueue_scripts', so it runs properly. jQuery will load before custom.js because of the dependency.

3. Final Answer:

   The custom.js script will be loaded in the footer after jQuery -> Option A

4. Quick Check:

   Dependency + footer true = load after jQuery in footer [OK]

Hint: Footer loading = last parameter true; dependencies load first [OK]

Common Mistakes:

• Confusing footer true with header loading
• Forgetting to hook function to wp_enqueue_scripts
• Ignoring script dependencies

4. Identify the error in this code snippet that tries to enqueue a JavaScript file:

function add_my_script() {
  wp_enqueue_script('my-script', get_template_directory() . '/js/script.js');
}
add_action('wp_enqueue_scripts', 'add_my_script');

medium

A. Using wrong function name add_action instead of add_script

B. Missing the version parameter in wp_enqueue_script

C. Not hooking to wp_head action

D. Using get_template_directory() instead of get_template_directory_uri() for URL

Solution

1. Step 1: Check the URL function used

   get_template_directory() returns a server path, not a URL. For enqueuing scripts, a URL is needed, so get_template_directory_uri() should be used.

2. Step 2: Verify other parts

   The version parameter is optional, so missing it is not an error. Hooking to wp_enqueue_scripts is correct. add_action is the right function to hook.

3. Final Answer:

   Using get_template_directory() instead of get_template_directory_uri() for URL -> Option D

4. Quick Check:

   Use URI function for URLs, not directory path [OK]

Hint: Use get_template_directory_uri() for URLs, not get_template_directory() [OK]

Common Mistakes:

• Using server path instead of URL for script source
• Confusing hooks like wp_head vs wp_enqueue_scripts
• Thinking version parameter is mandatory

5. You want to enqueue two CSS files: main.css and theme.css. theme.css depends on main.css. Which code correctly enqueues both with dependency and versioning?

hard

A. wp_enqueue_style('main-style', get_template_directory_uri() . '/main.css', array(), '1.0');
wp_enqueue_style('theme-style', get_template_directory_uri() . '/theme.css', array('main-style'), '1.1');

B. wp_enqueue_style('theme-style', get_template_directory_uri() . '/theme.css', array(), '1.1');
wp_enqueue_style('main-style', get_template_directory_uri() . '/main.css', array('theme-style'), '1.0');

C. wp_enqueue_style('main-style', get_template_directory_uri() . '/main.css', array('theme-style'), '1.0');
wp_enqueue_style('theme-style', get_template_directory_uri() . '/theme.css', array(), '1.1');

D. wp_enqueue_style('main-style', get_template_directory_uri() . '/main.css');
wp_enqueue_style('theme-style', get_template_directory_uri() . '/theme.css');

Solution

1. Step 1: Understand dependency order

   theme.css depends on main.css, so theme-style must list main-style as a dependency.

2. Step 2: Check versioning and parameters

   wp_enqueue_style('main-style', get_template_directory_uri() . '/main.css', array(), '1.0'); wp_enqueue_style('theme-style', get_template_directory_uri() . '/theme.css', array('main-style'), '1.1'); correctly enqueues main-style first with no dependencies, then theme-style with main-style as dependency and proper versions. Other options reverse dependencies or omit them.

3. Final Answer:

   wp_enqueue_style('main-style', get_template_directory_uri() . '/main.css', array(), '1.0'); wp_enqueue_style('theme-style', get_template_directory_uri() . '/theme.css', array('main-style'), '1.1'); -> Option A

4. Quick Check:

   Dependency array lists main-style for theme-style [OK]

Hint: List dependencies in array for dependent styles [OK]

Common Mistakes:

• Reversing dependency order
• Omitting dependency array
• Not specifying versions when needed