Transfer List

Dual-listbox for moving items between an available and a selected pane, ideal for permissions and settings UIs.

Components

Transfer List

input

interactive

beta

<arc-transfer-list>

Overview

TransferList presents the full universe of options split across two panes — everything not yet chosen on the left ("Available") and the current value on the right ("Selected"). Users mark items with a checkbox-style highlight, then move them across with the center controls, or move a single item instantly with a double-click or the Enter key. Pane titles are customisable via `sourceLabel` and `targetLabel`, and each pane header shows a live "checked of total" count. Options are supplied as an array of `{ value, label, disabled? }` objects and the component's `value` is the array of values currently in the Selected pane, kept in options order. With the `searchable` flag each pane gains its own case-insensitive filter input that narrows only that pane, and the move-all buttons respect the active filter. Disabled options render dimmed and can never be moved. The component is form-associated: give it a `name` and it submits one form entry per selected value, participates in `form.reset()`, and honours `<fieldset disabled>`. Both listboxes follow the WAI-ARIA multi-select listbox pattern — one tab stop each with a roving tabindex, arrow-key navigation, Space to toggle, and Ctrl+A to check every visible item — and moves are announced through a polite live region.

Guidelines

When to use

Use for medium-sized sets (roughly 5-100 items) where users assign a subset, such as role permissions or report columns
Enable `searchable` whenever a pane can hold more than a dozen items
Keep option labels short — one line each — so they do not truncate in narrow panes
Override `sourceLabel`/`targetLabel` with domain terms ("All permissions" / "Granted") for clearer context
Listen to `arc-change` to persist the selection; the detail carries the full value array after every move

When not to use

Do not use for a handful of options — a checkbox group or multi-select is lighter
Do not use for thousands of items without server-side narrowing; all options render in the panes
Do not repurpose the checked highlight as the selection itself — only items in the right pane are the value
Do not disable options without conveying elsewhere why they cannot be moved
Avoid placing two transfer lists side by side; each already spans two panes and needs the width

Features

Two labeled panes with live "checked of total" counts and customisable titles
Checkbox-style multi-highlight: mark any number of items, then transfer them in one action
Center controls to move checked items or all (filtered) items in either direction, auto-disabled when inapplicable
Double-click or Enter moves a single item across instantly
Optional per-pane case-insensitive filtering via the `searchable` flag
Full APG listbox keyboard support: roving tabindex, ArrowUp/Down, Home/End, Space to check, Ctrl+A to check all visible items
Focus stays in the same pane on the nearest remaining item after a move; moves are announced via a polite live region
Form-associated: submits one entry per selected value under `name` and supports form reset
Disabled options render dimmed and are excluded from every move operation
Responsive: panes stack vertically and controls rotate horizontal below ~560px container width

Preview

Usage

This component requires JavaScript. No pure HTML/CSS version is available — use the Web Component directly or a framework wrapper.

<arc-transfer-list
  id="permissions"
  name="permissions"
  searchable
  source-label="Available"
  target-label="Granted"
></arc-transfer-list>

<script>
  const tl = document.getElementById('permissions');
  tl.options = [
    { value: 'read', label: 'Read content' },
    { value: 'write', label: 'Write content' },
    { value: 'admin', label: 'Administer', disabled: true },
  ];
  tl.value = ['read'];
  tl.addEventListener('arc-change', (e) => {
    console.log(e.detail.value);
  });
</script>

import { TransferList } from '@arclux/arc-ui-react';

const options = [
  { value: 'read', label: 'Read content' },
  { value: 'write', label: 'Write content' },
  { value: 'admin', label: 'Administer', disabled: true },
];

<TransferList
  options={options}
  value={['read']}
  searchable
  sourceLabel="Available"
  targetLabel="Granted"
  onArcChange={(e) => console.log(e.detail.value)}
/>

<script setup>
import { TransferList } from '@arclux/arc-ui-vue';

const options = [
  { value: 'read', label: 'Read content' },
  { value: 'write', label: 'Write content' },
];
</script>

<template>
  <TransferList
    :options="options"
    :value="['read']"
    searchable
    source-label="Available"
    target-label="Granted"
    @arc-change="(e) => console.log(e.detail.value)"
  />
</template>

<script>
  import { TransferList } from '@arclux/arc-ui-svelte';

  const options = [
    { value: 'read', label: 'Read content' },
    { value: 'write', label: 'Write content' },
  ];
</script>

<TransferList
  {options}
  value={['read']}
  searchable
  source-label="Available"
  target-label="Granted"
  on:arc-change={(e) => console.log(e.detail.value)}
/>

import { Component } from '@angular/core';
import { TransferList } from '@arclux/arc-ui-angular';

@Component({
  imports: [TransferList],
  template: `
    <arc-transfer-list
      [options]="options"
      [value]="['read']"
      searchable
      sourceLabel="Available"
      targetLabel="Granted"
      (arcChange)="onChange($event)"
    ></arc-transfer-list>
  `,
})
export class PermissionsComponent {
  options = [
    { value: 'read', label: 'Read content' },
    { value: 'write', label: 'Write content' },
  ];

  onChange(e: CustomEvent) {
    console.log(e.detail.value);
  }
}

API

name string ='': Form field name. When set, the component submits one form entry per selected value.
disabled boolean =false: Disables the whole control, preventing interaction and reducing opacity.
source-label string ='Available': Heading for the left (available) pane. Attribute: source-label.
target-label string ='Selected': Heading for the right (selected) pane. Attribute: target-label.
options Array<{value:string,label:string,disabled?:boolean}> =[]: The full universe of items. Items whose value is in value render in the Selected pane; the rest render in Available.
value string[] =[]: Values currently in the Selected pane, kept in options order. Updated after every move and emitted via arc-change.
searchable boolean =false: Adds a filter input to each pane that narrows that pane only, case-insensitively. Move-all respects the filter.
readonly boolean =false: Prevents moving items between panes while the lists stay focusable and filterable; the selected values still submit with the form.
size 'sm' | 'md' | 'lg' ='md': Control size. md is the default; sm and lg scale the row height and list panels.
formAssociated boolean =true
properties object ={ // flag(), unlike `disabled`. The exclusion in props.js is specifically // about form-associated *platform* semantics: a `disabled` content // attribute that is merely present makes the element actually disabled // per the HTML spec, and formDisabledCallback assigns the property back, // so no converter can win. Neither of these is platform-mapped — // `required` is enforced by _computeValidity() below and `readonly` by // each component's own interaction handlers — so the stock converter buys // nothing here and costs the usual bug: `required="false"` read as true, // blocking submission of a form the author meant to leave optional. // Finding #48's shape, across all 26 form controls at once. required: flag(false), readonly: flag(false), }: Lit merges static properties up the prototype chain, so every consumer gets these without declaring them. required participates in constraint validation below; readonly reflects for styling and is enforced by each component's interaction handlers (the mixin can't know which gestures mutate state).
autoValidates boolean =true: Components that run their own constraint-validation logic (pattern checks, range checks) opt out of the automatic required sync by overriding this to false, and own the whole validity flag set instead.
form
validity
validationMessage
required boolean =false

Methods

checkValidity() →boolean: Whether the control currently satisfies its constraints, per the native constraint-validation API. Fires invalid on the element when it does not, and reports nothing to the user.
reportValidity() →boolean: As checkValidity(), but also shows the browser's validation message against the control when it fails.

Events

arc-change detail: { value: string[] }: Fired after every move with { value } -- the current array of selected values.

Transfer List

Overview

Guidelines

When to use

When not to use

Features

Preview

Usage

API

Methods

Events

See Also

Docs

Project

Arclight