I’ve been searching for this a while and it led me here. Echoing the disappointment. There is nothing obvious in CommonUI or in Lyra. The guy doing the video made it sound like this is an uncommon use, but keyboard menu navigation is exceptionally common and for a lot of games it’s really not sufficient to not have it in a production-ready game.
Unlike the guy who made this video, I’ll actually come back and reply if I find the answer. Or maybe he never found it. You’d think with access to Epic’s staff and the plugin developer that shouldn’t be an issue.
I went and sifted through the CommonUI event handlers until I found one that triggered every time I changed the current menu item with a gamepad (and confirmed keyboard doesn’t trigger it). Had to build Debug Editor (source engine only) to debug it adequately.
If I set the input mode to Game or Game and Menu the input events trigger correctly, but to have mouse showing I have to set it to not capture.
Therefore, the correct option is “Game and Menu” with mouse “Not Capture” or “Capture During Mouse Down”, if you want keyboard input events to be detected.
Now I’m getting events for key presses but they’re still not navigating, because it’s using the mouse cursor for focus.
Changing Common Input Settings DefaultInputType to Gamepad and disabling SupportsMouseAndKeyboard allowed the keyboard to be detected as gamepad input. But this is no good if we want to have the option to use the mouse. It also means gamepad icons displayed for actions instead of keyboard keys which is also no good. Probably has more issues too if you proceed.
Every time the mouse/keyboard is reactivated, the UI gets it’s focus from what’s under the mouse cursor. This is the source of the issue, we need to tell it if the last input device was a navigable key press, to NOT get focus from mouse, if we could do that, we would not have any more issues.
I’ve been at it for a while and I’m now too brain fried to continue. If I come back to this I’m sure I will find the correct solution, but my game doesn’t need to have it, but it should have it, as should most games I think.
Hopefully if someone else finds the solution they will post it here too.
TLDR: Set input mode to “Game and Menu”, set mouse to “Not Capture”. Now you get navigation key events for the keyboard. The remaining issue is that when the keyboard and mouse is active the focus is taken from what’s under the mouse cursor which overrides the key events (I do believe it’s probable that they change it, but in the same frame it is just changed back, or more likely rejected because mouse is currently used for focus).
One place worth looking may be void UCommonInputSubsystem::SetCurrentInputType(ECommonInputType NewInputType) where it calls SlateApplication.UsePlatformCursorForCursorUser(true); every time you reactivate the mouse.
