# How do I use Libgdx viewport for UI?

I am using LibGDX to make a game for Android and I am using 2 Viewports. One for UI and one for the actual game content. My problem is I can't find a good way to scale my UI using a Viewport.

This is a picture of my UI using a FitViewport:

As you can see it adds space on the top and bottom to fit the screen, but I want my pause button to stay on the top of the screen. I tried using a StretchViewport and that worked well for the pause button, but then the joysticks were no longer circle because they were distorted.

Is there a way to make a StretchViewport that only stretches the middle? (since nothing will be in the middle I don't care about that. Should I make a custom Viewport? And if so, how would I go about that? Thank you for any help!

What I ended up doing was having one Viewport that was an ExtendsViewport for just the joysticks. Then I added the pause button to the screen without using a table and manually set its size to a fraction of the physical screen resolution.
This isn't a great solution because it required another Stage that didn't use a Viewport and since I had another Stage I had to use an InputMultiplexor. Please let me know if you find a better solution that uses only one Stage.
I currently use a ScreenViewport on the GUI scene2d Stage, and set the size of the UI elements as inches, then just multiply it by Gdx.graphics.getPpix().