You can create a custom meta box under any post types by class AddMetaBox()
Files need to add:
classes/class-meta-box.php classes/class-form-fields-generator.php
Use on the theme:
Copy these file under “includes” directory and you can add in your theme directory as follows under “functions.php” file
require get_template_directory() . '/includes/class-form-fields-generator.php'; require get_template_directory() . '/includes/class-meta-box.php';
Main CSS & Js file need to add
css/pickplugins-options-framework.css js/pickplugins-options-framework.js
3rd Party CSS and JS file as need
css/codemirror.css css/fontawesome.min.css css/jquery-ui.css css/select2.min.css js/select2.min.js js/codemirror.min.js js/form-field-dependency.js
Example:
Please see the following file is providing a demo input field under the category
example/functions-meta-box.php