NSViewRepresentable overlaps scrollbar making it impossible to click

Question

When a NSViewRepresentable is embedded in a SwiftUI ScrollView AND the "show scroll bar" system setting is set to "When scrolling", it is impossible to drag or click the scrollbar.

I am trying to solve this for a while now, but I am running out of ideas. The only thing that worked is to use an AppKit NSScrollView and embed the SwiftUI views in that. But that opens up another can of worms.

• Has anyone seen this before?
• Any ideas how to fix this? Seems like a bug to me. But I wonder if anyone can think of a valid workaround?

Please check my minimal example: https://github.com/paxos/NSViewRepresentableScrollBug

Answer 1

I've encountered this too. It does seem to be a bug.

My workaround is to set an overlay with a very low (but non-zero) opacity on the NSViewRepresentable. Apparently this prevents mouse input from falling through the scrollbars, but still allows the expected interactions while being visually imperceptible. For example:

ScrollView {
    MyNSViewRepresentable()
        .overlay(Color.white.opacity(0.001))
}

This isn't perfect - in my case, I have a crosshair cursor set on the underlying NSView. It remains a crosshair instead of a pointer while using the scrollbars, but at least it grabs and moves them just fine.