Implement WinUI 3 scrolling for scrollviews.

[J0nathan550]

I wish to have smooth accelerated scrolling from WinUI 3 in WPF.

Here is the comparing of the scrolling in WPF / WinUI 3

2025-08-02.11-13-39.mp4

[miloush]

ScrollViewer.CanContentScroll="False"

Edit: VirtualizingPanel.ScrollUnit="Pixel" is better in this case as it keeps virtualization enabled

[J0nathan550]

ScrollViewer.CanContentScroll="False"

This doesn't implement the smooth scrolling. Of WinUI 3, in WPF.

Is there "inertia"?

[miloush]

It does let you scroll not by items, but by pixels, so grabbing the scrollbar thumb should behave similarly. With wheel events though, even then the VirtualizationStackPanel uses predefined amounts per rotation:

wpf/src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Controls/ScrollViewer.cs

Lines 2866 to 2867 in 4bd6464

	internal const double _scrollLineDelta = 16.0; // Default physical amount to scroll with one Up/Down/Left/Right key
	internal const double _mouseWheelDelta = 48.0; // Default physical amount to scroll with one MouseWheel.

wpf/src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Controls/VirtualizingStackPanel.cs

Lines 299 to 303 in 4bd6464

	int lines = SystemParameters.WheelScrollLines;
	bool isHorizontal = (Orientation == Orientation.Horizontal);
	double newOffset = (IsPixelBased || isHorizontal)
	? VerticalOffset - lines * ScrollViewer._scrollLineDelta
	: NewItemOffset(isHorizontal, (double)-lines, fromFirst:true);

There doesn't seem to be a way to configure the step amount.

As for inertia, it is implemented for touch, but not for wheel scrolling.

[J0nathan550]

is there a way to simulate the actual WinUI 3 scrolling?