UMG Slider Not Responding To Touch Input

I have a slider in my HUD widget and it works fine with mouse input, however, if I launch in Mobile Preview or change the Input in Project Settings to interpret mouse events as touch events, the bar does not respond or update when it is clicked.

I have verified this by creating a completely blank project with nothing but a slider control in the HUD. If I set up the project as a Windows/Console project, the slider works properly. As soon as I change it to a Mobile/Tablet project or change the input settings to interpret mouse clicks as touch events, it does not change when clicked.

There is nothing bound to the value of the slider.

Do I have to create a custom SSlider class that handles OnTouchBegin, OnTouchMove and OnTouchEnd? Regular buttons work fine without having to do any custom touch event handling.

I actually have this same issue on the 4.9 r4 preview. For whatever reason, as soon as I turn off “enable mouse click for touch” the sliders begin to work just fine.

This was resolved in 4.9.2

Has this issue returned in 4.15? I noticed this issue today after updating and was able to reproduce the issue in the exact same way as described above.

Ok, the problem doesn’t happen on device, it is only a side effect of using mouse to mimic touch interactions. I assume when you click and drag it begins simulating a touch and drag action, rather than simulating an HMD.