anchor

Summary

Positions a floating element against a target and tracks geometry, scroll, and resize changes.

Updates inline positioning and size constraints, and records the chosen side in data-anchor-placement. Call the returned cleanup function when the surface closes or unmounts. Cleanup stops tracking but leaves the last applied styles and placement attribute in place.

Signature

function anchor(
  floating: HTMLElement,
  anchorTarget: AnchorTarget,
  options: AnchorOptions,
): () => void

Parameters

floating

Element to position.

anchorTarget

Anchor element or viewport coordinates.

options

Placement, alignment, and offsets.

Returns

Cleanup function that stops polling and removes scroll and resize listeners.