[WASM][Desktop][ScrollViewer] Unable to Scroll Horizontally with Mouse Wheel

[erikvilima]

Current behavior

When using the ScrollViewer on a WASM or Desktop (tested on Windows only) platform, horizontal scrolling via the mouse wheel is not functioning as expected. It works on WinAppSdk.

Expected behavior

Horizontal scrolling should work when using the mouse wheel to navigate horizontally within the ScrollViewer (if the content overflows horizontally).

How to reproduce it (as minimally and precisely as possible)

Repro app: UnoApp5.zip

1. Add a ScrollViewer element with horizontal content (e.g., a horizontally scrolling ItemsRepeater or other horizontally overflowing content).
2. Use the mouse wheel to attempt horizontal scrolling.
3. Notice that the horizontal scroll does not occur, even though the vertical scroll works as intended.

Workaround

None

Works on UWP/WinUI

Yes

Environment

Uno.WinUI / Uno.WinUI.WebAssembly / Uno.WinUI.Skia

NuGet package version(s)

Uno.Sdk: 5.7.0-dev.120

Affected platforms

• WASM
• Desktop

IDE

Visual Studio 2022

IDE version

17.12.4

[ramezgerges]

@eriklimakc I've tested the repro and I'm not able to reproduce on either WASM or Skia. Just to clarify, you can't horizontally scroll with a mouse as far as I know, only with a touchpad (this is the same on WinUI too).

[erikvilima]

@eriklimakc I've tested the repro and I'm not able to reproduce on either WASM or Skia. Just to clarify, you can't horizontally scroll with a mouse as far as I know, only with a touchpad (this is the same on WinUI too).

@ramezgerges Actually, you can scroll horizontally with the mouse wheel on WinAppSdk. Just hover the mouse pointer over the list and scroll with the moouse wheel - it’ll move horizontally. If you move the pointer away from the list, then it scrolls vertically instead.

Recording.2025-02-13.073433.mp4