How do I set a different icon for a particular file type that has specific content?
Specifically, I'm trying to set a custom icon for an in-house XML file (similar to how the IDEA plugin icon is different than a regular XML file icon).
The file typically is located at a known place in the directory structure and has a known name, but ideally Id like to be able to check for the existence of an in-house XML element (so any *.xml file with the right contents will have the custom icon)
After a Google search, it looks like IconProvider has something to do with it, but I didnt find anything about how to register this new IconProvider with IDEA and I didnt see anything about checking the contents of the file.
What are the specifics for the icon (size, format and number of colors)?