Module scrollbar 

An explicit scrollbar: a track, a thumb that reports the scroll position, and a thumb the user can drag.

A scroll indicator that only reports is half a scrollbar. On a desktop, and on any platform driven by a mouse, the bar is also a control: grabbing the thumb and pulling it is how a long document is crossed, and a bar that cannot be grabbed sends the user back to the wheel for every long jump.

The thumb geometry is crate::scrollbar, shared with the curved indicator a round watch draws, so both answer “how long is the thumb and where does it sit” the same way. The drag is Modifier::draggable, so pulling a thumb obeys the same touch slop and axis locking as scrolling the content itself.

Structs

ScrollbarColors

The colours a Scrollbar paints with.

ScrollbarSpec

How a Scrollbar is drawn and how short its thumb may get.

Constants

DEFAULT_MIN_THUMB_EXTENT

How short the thumb may get, in logical pixels.

DEFAULT_SCROLLBAR_THICKNESS

How wide a bar is across its short axis.

Functions

HorizontalScrollbar

A horizontal scrollbar for state.

Scrollbar

A scrollbar along axis, drawn and bounded by spec.

VerticalScrollbar

A vertical scrollbar for state, drawn down the space the modifier gives it.

draw_scrollbar

Draws a scrollbar into a scope whose bounds are the whole bar.