Preloader for js files. How to show loading animation until js files are loaded?

Question

JavaScript

In my threejs, models in js format are loaded.
I need to hide the scene until the models are fully loaded

Answer 1

The script tag has an onload event.
In the simplest version, it is enough to make a counter, in which to place the number of requested resources, and hang a handler on onload, with the decrement of the counter. If it reaches zero, everything is loaded.

Answer 2

Alternatively, load the main JS files. After the event onload / $(document).ready - load large files with models via AJAX.
Thus, you will kill several birds with one stone: the user does not have to wait for the page to fully load, he sees the preloader and understands that he needs to wait more; you will be able to control the download state, "if loaded and connected - then".