ScrollBar

ScrollBar is the abstract base for standalone scroll bars.

Use VScrollBar (vertical) or HScrollBar (horizontal).

ScrollBar

Basic usage

Scrollbars are typically used through ScrollViewer, but can be used directly:

new VScrollBar()
    .Minimum(0)
    .Maximum(100)
    .Value(30);

In most apps you should prefer ScrollViewer + IScrollable, because it keeps viewport/extent synchronized and avoids manual offset math.

Behavior and interaction

Clicking the track pages up/down (or left/right).
Dragging the thumb sets the value proportionally.
Scrollbars can be focused to enable keyboard interaction (arrow keys/page keys).

Binding to a scroll model

When used inside ScrollViewer, scrollbars are automatically bound to the target ScrollModel:

ScrollModel.OffsetX/OffsetY maps to scrollbar value,
ScrollModel.ViewportWidth/ViewportHeight maps to thumb size,
ScrollModel.ExtentWidth/ExtentHeight maps to range.

If you host a scrollbar directly, you are responsible for keeping its range/value consistent with the content.

Defaults

VScrollBar: HorizontalAlignment = Align.Start, VerticalAlignment = Align.Stretch
HScrollBar: HorizontalAlignment = Align.Stretch, VerticalAlignment = Align.Start

Styling

ScrollBarStyle controls track/thumb rendering and colors.