Widget On Demand

The Widget On Demand module provides widgets for form elements which should be loaded on demand.
It also ships with a trait to act as a framework for easy transforming any widget to a widget on demand.

When you edit a content entity all the entity's fields have widgets assigned which generate the form elements for each field. But there are use cases where the user simply wants to only edit a single element or add a new element and does not need all the form elements on the page loaded. Having that in mind and having complex widget form elements like text_format widgets which after render are replaced by an editor e.g. ckeditor makes the page really heavy and full of form elements which might not even be touched by the user but slow down the initial page load. That is the use case where Widget On Demand might be used. Now instead of loading e.g. all the form elements for the text editors and shipping at the initial request all the libraries for the editor replace to happen we only ship the view of the elements, but transformed in such a way that on submission it acts as it was just normally loaded form element. Multiple elements could still be rearranged without the need to load their form elements.

The magic happens when the user click on a single form element. In this moment an ajax callback will be executed to load the real form element inclusive all the libraries needed for it.

At the moment this module provides widget on demand implementations of the following widgets:
-Core
--Number field
--Textfield - Text (plain)
--Text area (multiple rows) - Text (plain, long)
-Text module
--Text field - Text (formatted)
--Text area (multiple rows) - Text (formatted, long)
--Text area with a summary - Text (formatted, long, with summary)