In Mac OS X Lion, let's say I have 3 apps running with windows visible (apps A, B, C). C is focused. I hit Command+H and C hides, revealing B. I hit Command+H again, hiding B and revealing A.
Now when I hit Command+H, A hides, revealing B.
How can I hide all windows using this, or a similar, method in macOS?
You can hide all of the applications that are running except for Finder.
If you have no Finder window open you can hide all open windows, but the Finder application will be in focus with no window visible.
It is not possible to hide Finder as it is like Explorer in Windows, it basically is the macOS environment.
As far as I know, the main way is just to "push" all of the windows off the desktop with the F11 key leaving only the desktop visible.
As per the Apple Support pages here there are three possibilities:
Show the desktop (hide all open windows) via F11.
Use Command + Option + M to minimize all open windows [to the dock].
Use Command + Option + H to hide all open windows except the one in focus.
As others have said, you can't hide the Finder environment (without modification).
As far as I know it's not possible. Mac OS must have at least ONE application with focus, even it must have ONE application running.
As a test, you can enable "Quit" menu option in Finder (http://osxdaily.com/2010/02/12/how-to-quit-the-finder/). Just login in "safe mode" (pressing SHIFT just after login in. In this way none application will be running except Finder. After quitting Finder, it will re-born automatically. It's the same concept to hide all applications. At least one (Finder at least) will be the focus application.
/System/Library/LaunchAgents/com.apple.Finder.plist.
Command + Option + H + M will do the trick, it will hide all applications. The effect is as same as show desktop in microsoft windows.
Another useful hotkey you may interested in:
Command + Option + H hide all applications except current
