# Tree view

A React component in [Beamline](https://beamline.io/)'s [Navigation](https://beamline.io/components/navigation) category. Live demo: https://beamline.io/components/tree-view

Nested folders and records with the full tree keyboard model (arrows, Home/End, *, type to jump), depth guides, counts and animated opening.

## Use it for

- Nested hierarchies: files, folders, teams, categories.

## Not for

- Flat lists ([item](https://beamline.io/components/item) or [table](https://beamline.io/components/table)).

## Anatomy

- tree
- row: chevron, icon, label, badge
- depth guides
- group

## States

- collapsed
- expanded
- focused
- selected
- disabled

## Keyboard

- ↑ ↓ visible rows
- Inline-end arrow opens/enters (Right in LTR, Left in RTL)
- Inline-start arrow closes/returns to parent (Left in LTR, Right in RTL)
- Home / End
- * opens all siblings
- type to jump
- Enter / Space selects

## Motion

Groups open and close by height over 200 ms; the chevron turns. The selected row's tint and rule are one plate that travels to the next row chosen (ui/lib/contour.ts); expanding or collapsing a branch places it without travel; a selected row inside a closed branch has no plate.

## Props

| Prop | Type | Default | Description |
| --- | --- | --- | --- |
| `nodes` | `{ id, label, icon?, badge?, disabled?, children? }[]` | — |  |
| `expandedIds / defaultExpandedIds / onExpandedChange` | `string[]` | — |  |
| `selectedId / defaultSelectedId / onSelect` | `string / (node) => void` | — |  |
| `aria-label` | `string` | — |  |
| `classNames` | `typed part classes` | — | See visualContract.slots; existing handlers, accessibility and internal measurement refs are preserved. |
| `style` | `CSSProperties` | — | Visual root inline styles. |
| `ref` | `HTMLUListElement` | — | Native visual root/control reference, composed with internal refs when present. |

## Dependencies

`lucide-react`

## Import

```tsx
import { TreeView } from "@/components/tree-view/tree-view";
```

## Get it

Tree view is part of Beamline: 190 React components and screens your coding agent (Claude Code, Codex, Cursor or any MCP client) installs into your app through Beamline's MCP server, as a ready-built package or as plain React source you can change. $49 one payment (regular $200), no subscription, a year of updates, one licence for your whole team. [Get Beamline](https://beamline.io/checkout?pack=complete) · [Connect your agent](https://beamline.io/connect)

## More in Navigation

- [Breadcrumb](https://beamline.io/components/breadcrumb): Where a page sits and the way back up; long paths keep the first and last two levels and fold the middle into a menu.
- [Menu bar](https://beamline.io/components/menubar): A desktop-style File / Edit / View bar for editor-like apps; each menu takes the same rows as the dropdown menu, and pointing moves between open menus.
- [Navigation menu](https://beamline.io/components/navigation-menu): A site or docs header whose sections open into one panel that resizes and slides between them; NavigationMenuCard is the standard link row.
- [Pagination](https://beamline.io/components/pagination): Moves through pages of a known length: first, last and the current page's neighbours, with an optional “41–60 of 468”; a phone shows “Page 6 of 24”.
- [Sidebar](https://beamline.io/components/sidebar): The app's main navigation: sections, items with counts and one level of sub-pages, an icon rail with tooltips (⌘B, the trigger or the edge), and a sheet…
- [Stepper](https://beamline.io/components/stepper): Where someone is in a multi-step flow: done steps carry a check, the current one a ring, and the line between marks fills as steps complete.
- [Tabs](https://beamline.io/components/tabs): Switches between panels of one object; one indicator slides to the active tab, counts sit beside labels, and a long row scrolls instead of wrapping.
- [User menu](https://beamline.io/components/user-menu): The account menu behind the avatar: who is signed in, status, theme, account pages and sign out with progress; a bottom sheet on phones.