core-components

Frontend & Expérience UX

Core component library and design system patterns. Use when building UI, using design tokens, or working with the component library.

Documentation

Core Components

Design System Overview

Use components from your core library instead of raw platform components. This ensures consistent styling and behavior.

Design Tokens

NEVER hard-code values. Always use design tokens.

Spacing Tokens

// CORRECT - Use tokens
<Box padding="$4" marginBottom="$2" />

// WRONG - Hard-coded values
<Box padding={16} marginBottom={8} />

| Token | Value |

|-------|-------|

| $1 | 4px |

| $2 | 8px |

| $3 | 12px |

| $4 | 16px |

| $6 | 24px |

| $8 | 32px |

Color Tokens

// CORRECT - Semantic tokens
<Text color="$textPrimary" />
<Box backgroundColor="$backgroundSecondary" />

// WRONG - Hard-coded colors
<Text color="#333333" />
<Box backgroundColor="rgb(245, 245, 245)" />

| Semantic Token | Use For |

|----------------|---------|

| $textPrimary | Main text |

| $textSecondary | Supporting text |

| $textTertiary | Disabled/hint text |

| $primary500 | Brand/accent color |

| $statusError | Error states |

| $statusSuccess | Success states |

Typography Tokens

<Text fontSize="$lg" fontWeight="$semibold" />

| Token | Size |

|-------|------|

| $xs | 12px |

| $sm | 14px |

| $md | 16px |

| $lg | 18px |

| $xl | 20px |

| $2xl | 24px |

Core Components

Box

Base layout component with token support:

<Box
  padding="$4"
  backgroundColor="$backgroundPrimary"
  borderRadius="$lg"
>
  {children}
</Box>

HStack / VStack

Horizontal and vertical flex layouts:

<HStack gap="$3" alignItems="center">
  <Icon name="user" />
  <Text>Username</Text>
</HStack>

<VStack gap="$4" padding="$4">
  <Heading>Title</Heading>
  <Text>Content</Text>
</VStack>

Text

Typography with token support:

<Text
  fontSize="$lg"
  fontWeight="$semibold"
  color="$textPrimary"
>
  Hello World
</Text>

Button

Interactive button with variants:

<Button
  onPress={handlePress}
  variant="solid"
  size="md"
  isLoading={loading}
  isDisabled={disabled}
>
  Click Me
</Button>

| Variant | Use For |

|---------|---------|

| solid | Primary actions |

| outline | Secondary actions |

| ghost | Tertiary/subtle actions |

| link | Inline actions |

Input

Form input with validation:

<Input
  value={value}
  onChangeText={setValue}
  placeholder="Enter text"
  error={touched ? errors.field : undefined}
  label="Field Name"
/>

Card

Content container:

<Card padding="$4" gap="$3">
  <CardHeader>
    <Heading size="sm">Card Title</Heading>
  </CardHeader>
  <CardBody>
    <Text>Card content</Text>
  </CardBody>
</Card>

Layout Patterns

Screen Layout

const MyScreen = () => (
  <Screen>
    <ScreenHeader title="Page Title" />
    <ScreenContent padding="$4">
      {/* Content */}
    </ScreenContent>
  </Screen>
);

Form Layout

<VStack gap="$4" padding="$4">
  <Input label="Name" {...nameProps} />
  <Input label="Email" {...emailProps} />
  <Button isLoading={loading}>Submit</Button>
</VStack>

List Item Layout

<HStack
  padding="$4"
  gap="$3"
  alignItems="center"
  borderBottomWidth={1}
  borderColor="$borderLight"
>
  <Avatar source={{ uri: imageUrl }} size="md" />
  <VStack flex={1}>
    <Text fontWeight="$semibold">{title}</Text>
    <Text color="$textSecondary" fontSize="$sm">{subtitle}</Text>
  </VStack>
  <Icon name="chevron-right" color="$textTertiary" />
</HStack>

Anti-Patterns

// WRONG - Hard-coded values
<View style={{ padding: 16, backgroundColor: '#fff' }}>

// CORRECT - Design tokens
<Box padding="$4" backgroundColor="$backgroundPrimary">


// WRONG - Raw platform components
import { View, Text } from 'react-native';

// CORRECT - Core components
import { Box, Text } from 'components/core';


// WRONG - Inline styles
<Text style={{ fontSize: 18, fontWeight: '600' }}>

// CORRECT - Token props
<Text fontSize="$lg" fontWeight="$semibold">

Component Props Pattern

When creating components, use token-based props:

interface CardProps {
  padding?: '$2' | '$4' | '$6';
  variant?: 'elevated' | 'outlined' | 'filled';
  children: React.ReactNode;
}

const Card = ({ padding = '$4', variant = 'elevated', children }: CardProps) => (
  <Box
    padding={padding}
    backgroundColor="$backgroundPrimary"
    borderRadius="$lg"
    {...variantStyles[variant]}
  >
    {children}
  </Box>
);

Integration with Other Skills

react-ui-patterns: Use core components for UI states
testing-patterns: Mock core components in tests
storybook: Document component variants
Utiliser l'Agent core-components - Outil & Compétence IA | Skills Catalogue | Skills Catalogue