This is an example plugin for the Fictioneer WordPress theme to work off. It works exactly as any other plugin, just with some ready-made functions to properly link it to the theme. Do not forget to change any names, prefixes, constants, and the text domain.
Hooked into is_protected_meta, this function prevents meta fields from being changed in the editor. The interface is disabled in Fictioneer by default, but that does not mean a tech-savvy user cannot get around it. The function checks whether a meta key starts with a certain prefix (fcnbp_ for the example) and protects it from such manipulation. Alternatively, you can start your meta keys with an underscore (e.g. _my_meta_field) to achieve the same without the need for this function.
Hooked into after_setup_theme, this function checks whether Fictioneer or a child theme is active. If not, the plugin is deactivated to prevent errors.
Displays an admin notice if the theme is forcefully deactivated by fcnbp_check_theme().
Hooked into fictioneer_admin_settings_plugins, this function adds a card to the Fictioneer settings plugins page. Any options and configurations should be done here, unless you add a completely new admin menu page. The look is mostly left to you.
An example on how to add frontend styles and scripts for the plugin.
An example on how to add admin styles and scripts for the plugin.