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SidebarPro4
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What’s new80 new
BlocksSidebar

SidebarPro

App and docs sidebars: a folding rail, a workspace switcher, a mail shell, and a docs tree.

4 variants

InboxA mail sidebar whose Compose button grows into a composer and whose folders take dropped mail.

Live block · sample data

When to use

  • The shell of a mail or messaging app.
  • Inboxes where messages are dragged onto folders.
  • Mail clients with row quick actions and a compose window.

When not to use

  • Use inbox-triage for a focused one-at-a-time triage flow.
  • Use notification-center for app notifications.
  • Use workspace-sidebar for general app navigation.

Installation

Pro source and install commands unlock with a Pro plan.

Usage

Use this as the shell of a mail or messaging app. Load folders, labels, and messages from your mail API, persist moves and stars through it, and connect Send and drafts to your outbox; sending and saving in the preview are simulated.

example.tsx
1import { InboxSidebar } from "@/registry/blocks/inbox-sidebar/inbox-sidebar";2 3export default function MailPage() {4  return (5    <InboxSidebar6      onCollapsedChange={(collapsed) => localStorage.setItem("mail-rail", String(collapsed))}7    />8  );9}
Built fromAvatarAnimated counterTooltipButton

API reference

InboxSidebar

A mail shell with folders, labels, a message list you can drag onto folders, row quick actions, and a Compose button that grows into a composer. Folders, messages, and sending are simulated.

PropTypeDefaultDescription
defaultCollapsedbooleanfalseStart with the sidebar collapsed to its icon rail.
onCollapsedChange(collapsed: boolean) => void–Called when the sidebar collapses or expands, from the toggle or the [ shortcut.

Keyboard interactions

[
Toggles the icon rail when focus is not in a text field, menu, or dialog.
E
On a message row, archives or moves it with its quick action.
S
On a message row, toggles the star.
Cmd/Ctrl+Enter
Sends from the composer.
Escape
Closes the composer and saves a draft, or cancels a drag in progress.

Accessibility

  • The composer is a role="dialog" labelled by its title.
  • Moves, stars, and sends are announced through a polite status region, and rail icons have tooltips.
  • Every drag action has a keyboard or menu alternative.

Motion

  • Compose grows into the composer through a shared layoutId, and unread counts roll.
  • Dropped messages leave the list with layout animation while the target folder pulses.
  • Reduced motion makes the morph and list changes instant.

Responsive behavior

  • Below 720px container width the sidebar is locked to its 64px icon rail; below 420px row labels are hidden.
  • Dragging to folders works with a mouse only; touch uses the row menu and quick actions.

Performance

  • The shell is a fixed 660px tall and the message list is not virtualized; page long mailboxes.
  • Sidebar width springs through one motion value, and a ResizeObserver detects the narrow layout.

Notes for AI

Give your coding assistant the Markdown reference instead of screenshots.

  • Use as the shell of a mail or messaging app.
  • Load folders, labels, and messages from your mail API, persist moves and stars through it, and connect Send and drafts to your outbox.
  • Composes Arc avatar, animated-counter, tooltip, and button.
/components/blocks/sidebar/markdown

The full library index for assistants is at /llms.txt.

Related

Inbox triageProBlockProcess a focused inbox with archive, snooze, and restore actions.Sidebar: WorkspaceProBlockA product sidebar with a workspace switcher, live search, draggable favorites, and inline projects.Sidebar: App railProBlockAn app shell whose sidebar folds into an icon rail and slides in as a sheet on phones.Notification centerBlockA home for updates with read state, grouped information, and animated disclosure.Swipe actionsComponentReveal row actions with a swipe, or from the same actions in a menu.
PreviousAI composerNextSettings page
Arc · 75 block pagesllms.txt

On this page

  • Preview
  • When to use
  • When not to use
  • Installation
  • Usage
  • API reference
  • Keyboard
  • Accessibility
  • Motion
  • Responsive behavior
  • Performance
  • Notes for AI
  • Related
View as Markdown
Sofia Ramirezsofia@fieldnote.studio

Inbox

700123456789 messages, 400123456789 unread

Drag a message onto a folder, or use Move to

Drag a message onto a folder, or use Move to