Composable Svelte Components

This skill covers the UI component library for Composable Svelte applications, focusing on shadcn-svelte components and integration patterns.

For Specialized Components: See dedicated skills for graphics (3D), code (editors/media), charts (data viz), and maps (geospatial).

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COMPONENT LIBRARY OVERVIEW

Composable Svelte includes 73+ shadcn-svelte components for building modern UIs. All components integrate with the Composable Architecture via props and state management.

Integration Pattern:

• Props for configuration (labels, variants, styles)
• State from $store for reactive data
• Dispatch actions for user interactions

Package Organization:

• @composable-svelte/core - UI components (this skill)
• @composable-svelte/graphics - 3D graphics (see composable-svelte-graphics skill)
• @composable-svelte/code - Code editors, media players (see composable-svelte-code skill)
• @composable-svelte/charts - Data visualization (see composable-svelte-charts skill)
• @composable-svelte/maps - Interactive maps (see composable-svelte-maps skill)

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NAVIGATION COMPONENTS

Purpose: Overlay-based UI elements for state-driven navigation.

Integration Pattern: State-driven open/close via store, dismiss via PresentationAction.

See composable-svelte-navigation skill for implementation details. This section provides REFERENCE only.

Modal

Full-screen overlay with backdrop, centered content.

When to use: Primary actions, form submissions, important warnings.

Props:

• open: boolean - Whether modal is open
• onOpenChange: (open: boolean) => void - Callback when open state changes

import { Modal } from '@composable-svelte/core/components';

{#if modalStore}
  <Modal
    open={true}
    onOpenChange={(open) => !open && modalStore.dismiss()}
  >
    <ModalContent store={modalStore} />
  </Modal>
{/if}

Sheet

Bottom drawer that slides up (mobile-first).

When to use: Mobile-first UIs, filters, settings panels.

Props:

• open: boolean
• onOpenChange: (open: boolean) => void

Drawer

Side panel that slides from left or right.

When to use: Navigation menus, sidebars, settings.

Props:

• side: 'left' | 'right' - Which side to slide from
• open: boolean
• onOpenChange: (open: boolean) => void

Alert

Confirmation dialog, centered, smaller than Modal.

When to use: Destructive actions, confirmations, yes/no decisions.

Props:

• open: boolean
• onOpenChange: (open: boolean) => void

Popover

Contextual menu positioned near trigger element.

When to use: Dropdown menus, tooltips, context menus.

Props:

• open: boolean
• onOpenChange: (open: boolean) => void

---

FORM COMPONENTS

Purpose: User input elements that integrate with Composable Architecture.

Integration Pattern: Value from $store.state, dispatch on change, validation state from store.

See composable-svelte-forms skill for full patterns.

Input

Text input field with variants.

Types: text, email, password, number, tel, url, search, date, time.

Props:

• type: string - Input type
• value: string - Current value
• oninput: (e: Event) => void - Change handler
• placeholder: string - Placeholder text
• disabled: boolean - Disabled state

import { Input } from '@composable-svelte/core/components';

<Input
  type="text"
  value={$store.name}
  oninput={(e) => store.dispatch({ type: 'nameChanged', name: e.currentTarget.value })}
  placeholder="Enter name"
  disabled={$store.isSubmitting}
/>

{#if $store.nameError}
  <span class="error">{$store.nameError}</span>
{/if}

Select

Dropdown selector.

Props:

• value: string - Selected value
• onValueChange: (value: string) => void - Selection handler

import { Select, SelectTrigger, SelectContent, SelectItem } from '@composable-svelte/core/components';

<Select
  value={$store.category}
  onValueChange={(value) => store.dispatch({ type: 'categoryChanged', category: value })}
>
  <SelectTrigger>
    <SelectValue placeholder="Select category" />
  </SelectTrigger>
  <SelectContent>
    <SelectItem value="electronics">Electronics</SelectItem>
    <SelectItem value="clothing">Clothing</SelectItem>
    <SelectItem value="food">Food</SelectItem>
  </SelectContent>
</Select>

Checkbox

Boolean toggle with label.

Props:

• checked: boolean - Checked state
• onCheckedChange: (checked: boolean) => void - Toggle handler

import { Checkbox } from '@composable-svelte/core/components';

<Checkbox
  checked={$store.agreeToTerms}
  onCheckedChange={(checked) => store.dispatch({ type: 'toggleTerms', checked })}
>
  I agree to the terms and conditions
</Checkbox>

RadioGroup

Mutually exclusive options.

Props:

• value: string - Selected value
• onValueChange: (value: string) => void - Selection handler

import { RadioGroup, RadioGroupItem } from '@composable-svelte/core/components';

<RadioGroup
  value={$store.plan}
  onValueChange={(value) => store.dispatch({ type: 'planChanged', plan: value })}
>
  <RadioGroupItem value="free">Free</RadioGroupItem>
  <RadioGroupItem value="pro">Pro ($9/mo)</RadioGroupItem>
  <RadioGroupItem value="enterprise">Enterprise ($99/mo)</RadioGroupItem>
</RadioGroup>

Switch

Toggle switch.

Props:

• checked: boolean
• onCheckedChange: (checked: boolean) => void

Textarea

Multi-line text input.

Props:

• value: string
• oninput: (e: Event) => void
• rows: number - Number of visible rows
• placeholder: string

Combobox

Autocomplete dropdown.

Props:

• value: string - Selected value
• options: Array<{ label: string; value: string }> - Available options
• onValueChange: (value: string) => void - Selection handler
• onSearchChange: (query: string) => void - Search handler

---

DATA DISPLAY COMPONENTS

Purpose: Display data from store.state, often derived/computed.

Integration Pattern: Map from store.state arrays, use $derived for filtering/sorting.

Table

Tabular data display with sorting/filtering.

When to use: Lists of structured data, data grids.

import { Table, TableHeader, TableRow, TableHead, TableBody, TableCell } from '@composable-svelte/core/components';

<Table>
  <TableHeader>
    <TableRow>
      <TableHead>Name</TableHead>
      <TableHead>Email</TableHead>
      <TableHead>Status</TableHead>
    </TableRow>
  </TableHeader>
  <TableBody>
    {#each $store.users as user (user.id)}
      <TableRow>
        <TableCell>{user.name}</TableCell>
        <TableCell>{user.email}</TableCell>
        <TableCell>{user.status}</TableCell>
      </TableRow>
    {/each}
  </TableBody>
</Table>

Card

Container for related content with header/footer.

When to use: Product cards, user profiles, content previews.

import { Card, CardHeader, CardTitle, CardDescription, CardContent } from '@composable-svelte/core/components';

{#each $store.products as product (product.id)}
  <Card>
    <CardHeader>
      <CardTitle>{product.name}</CardTitle>
      <CardDescription>{product.category}</CardDescription>
    </CardHeader>
    <CardContent>
      <p>${product.price}</p>
      <Button onclick={() => store.dispatch({ type: 'addToCart', productId: product.id })}>
        Add to Cart
      </Button>
    </CardContent>
  </Card>
{/each}

Badge

Small label/tag.

Variants: default, success, secondary, destructive, outline.

import { Badge } from '@composable-svelte/core/components';

<Badge variant={$store.status === 'active' ? 'success' : 'secondary'}>
  {$store.status}
</Badge>

Avatar

User profile image with fallback.

import { Avatar, AvatarImage, AvatarFallback } from '@composable-svelte/core/components';

<Avatar>
  <AvatarImage src={$store.user?.avatarUrl} alt={$store.user?.name} />
  <AvatarFallback>{$store.user?.initials}</AvatarFallback>
</Avatar>

---

FEEDBACK COMPONENTS

Purpose: Communicate loading states, errors, and notifications.

Integration Pattern: Render based on loading/error/success state from store.

Toast

Temporary notification.

When to use: Success messages, errors, notifications.

import { toast } from '@composable-svelte/core/components';

// In reducer
case 'itemAdded':
  return [
    { ...state, items: [...state.items, action.item] },
    Effect.fireAndForget(async () => {
      toast.success('Item added successfully');
    })
  ];

case 'itemDeleteFailed':
  return [
    { ...state, error: action.error },
    Effect.fireAndForget(async () => {
      toast.error('Failed to delete item');
    })
  ];

Progress

Linear progress indicator.

When to use: Upload progress, loading progress.

import { Progress } from '@composable-svelte/core/components';

{#if $store.uploadProgress !== null}
  <Progress value={$store.uploadProgress} max={100} />
  <p>{$store.uploadProgress}% uploaded</p>
{/if}

Skeleton

Loading placeholder with shimmer effect.

When to use: Content placeholders during loading.

import { Skeleton } from '@composable-svelte/core/components';

{#if $store.isLoading}
  <Skeleton class="h-4 w-full mb-2" />
  <Skeleton class="h-4 w-3/4 mb-2" />
  <Skeleton class="h-4 w-1/2" />
{:else}
  <p>{$store.content}</p>
{/if}

Spinner

Loading spinner.

Props:

• size: 'small' | 'medium' | 'large'

import { Spinner } from '@composable-svelte/core/components';

{#if $store.isLoading}
  <Spinner size="large" />
{/if}

---

LAYOUT COMPONENTS

Purpose: Organize UI with expand/collapse, tabs, resizable panels.

Integration Pattern: Expanded/active state lives in store, dispatch on user interaction.

Accordion

Expandable/collapsible sections.

When to use: FAQs, collapsible content sections.

import { Accordion, AccordionItem, AccordionTrigger, AccordionContent } from '@composable-svelte/core/components';

// State
interface FAQState {
  expandedItems: string[]; // Array of expanded item IDs
}

// Reducer
case 'toggleItem':
  return [
    {
      ...state,
      expandedItems: state.expandedItems.includes(action.itemId)
        ? state.expandedItems.filter(id => id !== action.itemId)
        : [...state.expandedItems, action.itemId]
    },
    Effect.none()
  ];

// Component
<Accordion>
  {#each $store.faqItems as item (item.id)}
    <AccordionItem value={item.id}>
      <AccordionTrigger
        onclick={() => store.dispatch({ type: 'toggleItem', itemId: item.id })}
        expanded={$store.expandedItems.includes(item.id)}
      >
        {item.question}
      </AccordionTrigger>
      <AccordionContent>
        {item.answer}
      </AccordionContent>
    </AccordionItem>
  {/each}
</Accordion>

Tabs

Tab navigation.

When to use: Multiple views of related content.

import { Tabs, TabsList, TabsTrigger, TabsContent } from '@composable-svelte/core/components';

// State
interface DashboardState {
  activeTab: 'overview' | 'analytics' | 'reports';
}

// Component
<Tabs value={$store.activeTab} onValueChange={(tab) => store.dispatch({ type: 'tabChanged', tab })}>
  <TabsList>
    <TabsTrigger value="overview">Overview</TabsTrigger>
    <TabsTrigger value="analytics">Analytics</TabsTrigger>
    <TabsTrigger value="reports">Reports</TabsTrigger>
  </TabsList>
  <TabsContent value="overview">
    <OverviewPanel store={store} />
  </TabsContent>
  <TabsContent value="analytics">
    <AnalyticsPanel store={store} />
  </TabsContent>
  <TabsContent value="reports">
    <ReportsPanel store={store} />
  </TabsContent>
</Tabs>

Collapsible

Single collapsible section.

When to use: Sidebar toggles, advanced settings.

import { Collapsible, CollapsibleTrigger, CollapsibleContent } from '@composable-svelte/core/components';

<Collapsible
  open={$store.sidebarExpanded}
  onOpenChange={(open) => store.dispatch({ type: 'toggleSidebar', open })}
>
  <CollapsibleTrigger>
    <Button>Toggle Sidebar</Button>
  </CollapsibleTrigger>
  <CollapsibleContent>
    <nav>
      <a href="/dashboard">Dashboard</a>
      <a href="/settings">Settings</a>
    </nav>
  </CollapsibleContent>
</Collapsible>

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SPECIALIZED COMPONENT PACKAGES

For specialized components beyond standard UI, see dedicated skills:

3D Graphics

Skill: composable-svelte-graphics Package: @composable-svelte/graphics Components: Scene, Camera, Light, Mesh Use cases: 3D visualizations, WebGPU/WebGL rendering, geometry (box, sphere, cylinder, torus, plane)

Code & Media

Skill: composable-svelte-code Package: @composable-svelte/code Components: CodeEditor, CodeHighlight, AudioPlayer, VideoEmbed, VoiceInput, NodeCanvas, StreamingChat Use cases: Code editing, syntax highlighting, media playback, voice recognition, visual programming, chat interfaces

Charts & Data Visualization

Skill: composable-svelte-charts Package: @composable-svelte/charts Components: Chart, ChartPrimitive, ChartTooltip Use cases: Data visualization, interactive charts, statistical plots

Maps & Geospatial

Skill: composable-svelte-maps Package: @composable-svelte/maps Components: Map, MapPrimitive, GeoJSONLayer, HeatmapLayer, Popup, TileProviderControl Use cases: Interactive maps, geospatial data, location-based features

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COMPONENT SELECTION DECISION TREE

Navigation Components

What kind of overlay?
│
├─ Full-screen important action → Modal
├─ Bottom panel (mobile-first) → Sheet
├─ Side panel (navigation/settings) → Drawer
├─ Quick confirmation (yes/no) → Alert
└─ Contextual menu (dropdown) → Popover

Form Components

What kind of input?
│
├─ Single line text → Input
├─ Multi-line text → Textarea
├─ Boolean toggle → Checkbox or Switch
├─ One from many options → RadioGroup or Select
├─ Autocomplete/search → Combobox
└─ Date/time → Input type="date" or Input type="time"

Data Display

What kind of data?
│
├─ Tabular data → Table
├─ List of items → Cards or List
├─ Status/label → Badge
├─ User profile → Avatar
└─ Metrics/stats → Card with metrics

Feedback

What kind of feedback?
│
├─ Loading state → Spinner or Skeleton
├─ Progress indicator → Progress
├─ Success/error notification → Toast
└─ Confirmation needed → Alert

---

CUSTOM COMPONENT GUIDELINES

Principles for Building Custom Components:

1. No $state for Application State: All state that affects behavior or can be tested must be in the store
2. Dispatch Actions: User interactions dispatch actions to the store
3. Read from Store: Render based on $store.state
4. Use $derived: For computed values derived from store state
5. Props for Configuration: Static configuration (labels, styles) can be props

Example Custom Component:

<script lang="ts">
  import type { Store } from '@composable-svelte/core';

  export let store: Store<State, Action>;
  export let label: string; // Static config
  export let variant: 'primary' | 'secondary' = 'primary'; // Static config

  // Derived from store
  const isDisabled = $derived($store.isLoading || $store.hasErrors);
  const displayText = $derived($store.count > 0 ? `${label} (${$store.count})` : label);
</script>

<button
  class={variant}
  disabled={isDisabled}
  onclick={() => store.dispatch({ type: 'buttonClicked' })}
>
  {displayText}
</button>

---

ACCESSIBILITY PATTERNS

Keyboard Navigation

All interactive components support keyboard navigation:

• Tab: Move focus between elements
• Enter/Space: Activate buttons, toggles
• Escape: Close modals, popovers, dropdowns
• Arrow keys: Navigate lists, select options

Screen Reader Support

Components include ARIA attributes:

• aria-label: Descriptive labels
• aria-expanded: Expanded/collapsed state
• aria-selected: Selected state
• role: Semantic roles

Focus Management

Components manage focus:

• Modal traps focus inside dialog
• Popover returns focus to trigger on close
• Forms focus first invalid field on submit

---

STYLING PATTERNS

Tailwind Integration

All components use Tailwind CSS classes:

<Button class="bg-primary text-primary-foreground hover:bg-primary/90">
  Click me
</Button>

Custom Styles

Override with custom CSS:

<Card class="custom-card">
  <CardContent>
    ...
  </CardContent>
</Card>

<style>
  .custom-card {
    background: linear-gradient(to right, #667eea 0%, #764ba2 100%);
  }
</style>

---

SUMMARY

This skill covers the component library for Composable Svelte:

1. Navigation Components: Modal, Sheet, Drawer, Alert, Popover
2. Form Components: Input, Select, Checkbox, RadioGroup, Switch, Textarea, Combobox
3. Data Display: Table, Card, Badge, Avatar
4. Feedback: Toast, Progress, Skeleton, Spinner
5. Layout: Accordion, Tabs, Collapsible
6. 3D Graphics: Scene, Camera, Light, Mesh (box, sphere, cylinder, torus, plane)
7. Component Selection: Decision trees for choosing components
8. Custom Components: Guidelines for building custom components
9. Accessibility: Keyboard, screen reader, focus management
10. Styling: Tailwind integration, custom styles

Remember: Props for config, state in store, dispatch for interactions. Use the right component for each use case.

For navigation implementation, see composable-svelte-navigation skill. For form integration, see composable-svelte-forms skill. For core architecture, see composable-svelte-core skill. For testing components, see composable-svelte-testing skill.