AurumBannerHost

Aurum's banner host — a thin slot that renders the single currently visible AurumBanner from hostState with a slide-from-top expand/collapse animation.

family	Feedback
platform	iOS 17+ · SwiftUI
source	`Sources/Aurum/Component/Feedback/AurumBannerHost.swift`

Aurum's banner host — a thin slot that renders the single currently visible AurumBanner from hostState with a slide-from-top expand/collapse animation.

Place at the top of the screen (above the header / content). Placed in the layout flow (first child of the root VStack), the animation smoothly pushes the content underneath down and releases it back — the structural-band behaviour. Placed in an .overlay(alignment: .top) it floats over content instead. Banners are persistent — there is no queue or timer; the caller owns the lifecycle.

This is codebase-only — there is no Figma node yet. It is proposal-grade orchestration glue, pending design; reconcile when design produces the spec. The visual is AurumBanner.

Intended use

Host slot for persistent, top-anchored, app- or page-level status: offline / no-connection, scheduled downtime, degraded service, account warnings. One host per screen, placed top-anchored. When the host touches the top screen edge the banner's tone colour bleeds under the status bar automatically while content stays clear.

Place the host top-anchored, above the header / content, so the strip reads as a structural band at the top edge.
Place the host in the layout flow (first child of the root VStack) when the banner should push content down rather than float over it.
Drive show(...) / dismiss() from the source of truth for the condition (e.g. a connectivity observer), so the banner mirrors live state.

Don’t

Use this for transient confirmations — that's AurumToastHost + showToast(...).
Mount more than one AurumBannerHost per screen — concurrent hosts fight for the top slot.
Give the host a fixed height — it occupies only the banner's natural height; anchor it with layout position, not frames.