How to Bundle Meta Box into Another Plugin to Create Custom Fields

If you want to use Meta Box to create custom fields or a settings page without installing it, there is another way that is bundling it into another plugin.

You may wonder why we need to do it. It’s because when you create a website for clients, it may be a good idea to hide information such as the used plugins. This time, bundling Meta Box into another plugin will be an effective way.

Let's see how to do it.

Bundle Meta Box into a Plugin

Create a New Plugin

In the wp-content folder > plugin, create a new folder named project-demo with a project-demo.php file inside. The php file has the following content:

<?php
/**
 * Plugin Name: Project Demo 
 * Plugin URI: https://metabox.io 
 * Version: 1.0
 * Author: Meta Box
 * Author URI: https://metabox.io
 */

Go to the plugins listing page in the Admin Dashboard, you’ll see a new plugin named Project Demo. Let's activate it.

Bundle Meta Box with Composer

We must download the necessary libraries of Meta Box into the plugin that you’ve created.

In the project-demo folder, we create a file named composer.json with the following content:

{
    "repositories":[
        {
            "type": "composer",
            "url": "https://wpackagist.org"
        }
    ],
    "require": {
        "wpackagist-plugin/meta-box": "^5",
    },
    "extra": {
        "installer-paths": {
            "vendor/meta-box/meta-box": ["wpackagist-plugin/meta-box"],
        }
    },
    "autoload": {
        "files": [
            "vendor/meta-box/meta-box/meta-box.php",
        ]
    }
}

Note: By this code, I just bundle the Meta Box plugin (free version) into the plugin I’ve created. If you want to add other Meta Box’s extensions to create advanced custom fields or settings pages, check out this file.

When bundling other extensions, especially the premium ones, you must enter the license key of the product (details in this file).

Back to the above code, there are some points that we should pay attention:

• "require": this is the declaration of the libraries that you need to download. In this example, I declare the Meta Box library only. You can refer to other code to declare the libraries of the extensions here.
• "extra": this is declaring a path of where we want to store the libraries.
• "autoload": require to load the libraries automatically when we activate the plugin.

Next, run the composer install command in the project-demo folder (make sure that you installed Composer).

After that, the project-demo folder will include these folders and files as follows:

Finally, you must run the following code in the project-demo.php file to download the libraries that you’ve declared:

require 'vendor/autoload.php';

If you are not familiar with using Composer to install Meta Box, you can learn about it here.

Now, you’ve finished bundling Meta Box into another plugin already. So you can try creating custom fields using this new plugin from now on.

Create Custom Post Types and Custom Fields

I’m going to use the created plugin which includes Meta Box to create a new custom post type named Project. Then, I will create a custom field for this post type.

Actually, this process is quite similar to when you install Meta Box directly on the website. The only difference is that if you don’t bundle extensions providing UI (such as Meta Box Builder, MB Custom Post Type & Custom Taxonomy) into the plugin as I did, you have to code manually. At the same time, instead of writing code to the function.php file, you must do it in the .php file of the created plugin (project-demo.php).

Follow the below steps and compare to the article “How to Create a Product Page using Meta Box Plugin”, you’ll see that.

Create the Project Post Type

Add the following code into the project-demo.php file:

// Create a new post type
function prefix_register_post_type_project(){
    $label = [
        'name'          => 'Projects',
        'singular_name' => 'Project',
    ];

    $args = [
        'labels'      => $label,
        'supports'    => ['title', 'editor', 'author', 'thumbnail', 'excerpt', 'comments'],
        'rewrite'     => [
            'slug'       => 'project',
            'with_front' => false,
            'feeds'      => true,
            'pages'      => true,
        ],
        'public'            => true,
        'show_ui'           => true,
        'menu_position'     => 20,
        'capability_type'   => 'page',
        'map_meta_cap'      => true,
        'has_archive'       => true,
        'query_var'         => 'project',
        'show_in_rest'      => true,
        'show_in_menu'      => true,
        'show_in_nav_menus' => true,
    ];
    register_post_type( 'project', $args );
}
add_action( 'init', 'prefix_register_post_type_project' );

Back to the Admin Dashboard, you’ll see a new menu named Projects. It’s the custom post type that you’ve created.

Create Custom Fields for Projects

To create custom fields, there are 2 options for you: manually code or generate code using Online Generator. Then, copy and paste this code (as the example below) into the project-demo.php file:

// Add custom fields for the Project post type
function prefix_add_fields_project( $meta_boxes) {
    $meta_boxes[] = [
        'title'      => 'Information project',
        'post_types' => 'project',
        'fields'     => [
            [
                'id'   => 'investors',
                'name' => 'Investors',
            ],
            [
                'id'   => 'customer',
                'name' => 'Customer',
            ],
            [
                'id'   => 'description',
                'name' => 'Description',
                'type' => 'textarea',
            ],
            [
                'id'   => 'image',
                'name' => 'Images',
                'type' => 'image_advanced',
            ],
        ],
    ];
    return  $meta_boxes;
}
add_filter( 'rwmb_meta_boxes', 'prefix_add_fields_project' );

Right now, try creating/editing an article in the Project post type, the fields will appear as follows:

Display the Project Fields

Create a Template for Single Page of the Project Post Type

Add the following code to the project-demo.php file:

// Register a new template for the single page of Project post type
function prefix_project_template( $template ) {
    if ( is_singular( 'project' ) ) {
        $template = plugin_dir_path( __FILE__ ) . 'project-template.php';
    }
    return $template;
}
add_filter( 'template_include', 'prefix_project_template', 99 );

Next, create a new file in the project-demo folder that named project-template.php (it must have the name as we’ve declared above) with the following content:

<?php get_header(); ?>
<div class="content">
    <h3><a href="<?php the_permalink() ?>"><?php the_title(); ?></a></h3>
    <p><?= get_the_date('d.m.Y'); ?></p>
</div>
<?php get_footer(); ?>

Get Custom Fields' Values

Add the following code to the content of the template file (project-template.php):

<div class="img-post">
    <?php 
    $images = rwmb_meta( 'image', ['size' => 'full'] );
    foreach ( $images as $image ) {
        echo '<img src="'. $image['url']. '">';
    }
    ?>
</div>
<div class="infomation">
    <?php
    $investors = rwmb_meta( 'investors' );
    $customer = rwmb_meta( 'customer' );
    $description = rwmb_meta( 'description' );
    ?>
    <table>
        <tr>
            <td class="col-1">Investors</td>
            <td><?php echo $investors; ?></td>
        </tr>
        <tr>
            <td class="col-1">Customer</td>
            <td><?php echo $customer; ?></td>
        </tr>
        <tr>
            <td class="col-1">Description</td>
            <td><?php echo $description; ?></td>
        </tr>
    </table>
</div>

At this time, in the single post page of the Project post type, the content will be displayed as follows:

Fields and their values are not displayed well, so we need to style them a bit.

Styling Fields

I create one more file named style.css in the project-demo folder. Then, I enqueue it into the project-demo.php file as following:

function prefix_project_styles() {
    wp_enqueue_style( 'prefix_main-style', plugin_dir_url( __FILE__ ) . '/style.css' );
}
add_action( 'wp_enqueue_scripts', 'prefix_project_styles' );

The structure of the project-demo folder is like this:

Depending on how you want to display the custom fields, you add the corresponding code to the style.css file. For example:

.information table, td {
    border: 1px solid black;
}

img {
    display: inline-block!important;
    height: auto;
    max-width: 200px!important;
    margin-right: 15px!important;
    margin-bottom: 20px;
}

.content {
    width: 800px;
    margin: 0 auto;
}

.col-1 {
    width: 30%;
}

After that, the fields’ values will be displayed as follows:

So you’ve finished creating a new custom post type and custom fields, then displaying them into the frontend by the new plugin that includes Meta Box.

You can refer to the entire source code which I used in this article here.

Last Words

Hopefully, you’ve had an additional way to use Meta Box for your WordPress theme or on the clients’ site that you don’t have to install or display the Meta Box menu in the Admin Dashboard. If you’re wondering anything, leave a comment. Finally, remember to follow our upcoming articles to dig in advanced techniques in development.