Suboptimal loading indicator for loading classes

[jvendetti]

In the master branch we have a "Loading Class..." indicator that displays in the center of the screen while BioPortal fetches class data. To reproduce:

1. Navigate to an ontology, e.g., SNOMEDCT
2. Select the Classes tab and type a class name in the "Jump to:" box
3. Select any class from the list of results

Notice that BioPortal immediately displays a "Loading Class..." indicator in the center of the screen that makes it clear and obvious to a user that BioPortal is retrieving / preparing to display the class data. I acknowledge that this indicator is kind of dated looking, but we have a lot of classes in the system that take > 5 seconds to load, so I consider it important.

The first time I selected a result from "Jump to:" in the sync-agroportal branch it looked like nothing happened and I thought the code was broken. Then about 7 seconds later the class I selected rendered, and I thought our loading indicator had simply been removed. It wasn't until I tested the functionality in AgroPortal that I realized there's a new loading indicator in the form of a thin blue line that appears at the very top of the page. I noticed the line on their site because they have a medium green header. In BioPortal I had no idea it was there - I think because it gets lost next to our dark blue header.

Screen.Recording.2024-11-15.at.4.08.01.PM.mov

[jvendetti]

As a first pass I might suggest changing the color of the loading indicator to... white maybe? However, I'm not certain if that would be sufficient. If we get complaints from end users I think we should revert to something more obvious like what we have now.

[mdorf]

Would this suffice as a first pass?
https://github.com/user-attachments/assets/dd27d17f-0290-4666-9bd5-6564b6c3aae3

[jvendetti]

That's definitely more obvious than the blue line. I think the appearance could do with more refining, but it you want to release it as-is I don't object.