You can use the APIs to add custom connections to the field connections menu in order to connect any kind of data you want.
Adds a connection related to posts.
Adds a connection related to archives.
Adds a connection related to the site.
Use these methods to add your connections within the fl_page_data_add_properties action. Each method accepts a key for your connection and a config array.
Note: Be sure to namespace the key for your connection in order to avoid possible collisions with other custom connections. For example, if your connection is called Post Title, the key should be my_namespace_post_title, where my_namespace is your custom namespace.
The following code example shows the method FLPageData::add_post_property() used within the fl_page_data_add_properties action.
The label for your connection that will show in the menu.
See the section below to add custom groups.
The type of connection. Use this when you connect a field to indicate what type of connections are available. For example, when you add a text field to a settings form, you can indicate that all of the string and HTML-based connections are available.
A reference to a function or class method that is used to retrieve the data for your connection.
The slug of a settings form that has been registered for this connection. A connection doesn't require a settings form, so this property is optional.
Adds settings to a post connection.
Adds settings to a archive connection.
Adds settings to a site connection.
Each method accepts a key for your form and a config array.
The following code example shows the use of the method that adds settings to a post connection.
See also the Beaver Builder Plugin article about customizing settings forms.
You can a group to field connections under. In the following screenshot, General and Author are groups that organize the field connections.