[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"skill:01M6G233P6F2CSFQ9D9D7PE6DQ":3,"skill-same:01M6G233P6F2CSFQ9D9D7PE6DQ":76},{"skillNo":4,"name":5,"nameZh":6,"description":7,"descriptionZh":6,"repositoryFullName":8,"ownerLogin":9,"ownerAvatarUrl":10,"ownerAccountNo":11,"ownerDisplayName":12,"repositoryNo":13,"starsCount":14,"licenseSpdxId":15,"licenseFileUrl":6,"sourceHtmlUrl":16,"categories":17,"keywords":23,"publishedAt":41,"linkOnly":42,"markdownContent":43,"markdownBody":44,"frontMatter":45,"refName":47,"commitSha":48,"skillDirectory":49,"forksCount":50,"repositoryHtmlUrl":51,"repositoryHomepageUrl":6,"ownerHtmlUrl":52,"ownerBlogUrl":53,"ownerDescription":54,"updatedAt":55,"install":56,"resources":69},"01M6G233P6F2CSFQ9D9D7PE6DQ","frontend-patterns",null,"Frontend development patterns for React, Next.js, state management, performance optimization, and UI best practices.","oabdelmaksoud\u002FAgention","oabdelmaksoud","https:\u002F\u002Favatars.githubusercontent.com\u002Fu\u002F50699149?v=4","01M6D5CVVN778ZCDP1WHS816SP","Omar Abdelmaksoud","01M6D8A4TE76V3DCSH3D94VG1V",2,"MIT","https:\u002F\u002Fgithub.com\u002Foabdelmaksoud\u002FAgention\u002Fblob\u002Fmain\u002Fupstream-sync\u002Fwork\u002Fecc\u002F.agents\u002Fskills\u002Ffrontend-patterns\u002FSKILL.md",[18],{"categoryNo":19,"categoryName":20,"taxonomyType":21,"taxonomyTypeDesc":22},"01JBSEEDCAT000000000000009","前端开发","SCENARIO","使用场景",[24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40],"patterns","frontend patterns","frontend","Optimization","next","frontend development","management","performance optimization","js","Next.js","ui","state","best practices","state management","development","react","performance","2026-11-10 10:12:30",false,"---\nname: frontend-patterns\ndescription: Frontend development patterns for React, Next.js, state management, performance optimization, and UI best practices.\norigin: ECC\n---\n\n# Frontend Development Patterns\n\nModern frontend patterns for React, Next.js, and performant user interfaces.\n\n## When to Activate\n\n- Building React components (composition, props, rendering)\n- Managing state (useState, useReducer, Zustand, Context)\n- Implementing data fetching (SWR, React Query, server components)\n- Optimizing performance (memoization, virtualization, code splitting)\n- Working with forms (validation, controlled inputs, Zod schemas)\n- Handling client-side routing and navigation\n- Building accessible, responsive UI patterns\n\n## Component Patterns\n\n### Composition Over Inheritance\n\n```typescript\n\u002F\u002F ✅ GOOD: Component composition\ninterface CardProps {\n  children: React.ReactNode\n  variant?: 'default' | 'outlined'\n}\n\nexport function Card({ children, variant = 'default' }: CardProps) {\n  return \u003Cdiv className={`card card-${variant}`}>{children}\u003C\u002Fdiv>\n}\n\nexport function CardHeader({ children }: { children: React.ReactNode }) {\n  return \u003Cdiv className=\"card-header\">{children}\u003C\u002Fdiv>\n}\n\nexport function CardBody({ children }: { children: React.ReactNode }) {\n  return \u003Cdiv className=\"card-body\">{children}\u003C\u002Fdiv>\n}\n\n\u002F\u002F Usage\n\u003CCard>\n  \u003CCardHeader>Title\u003C\u002FCardHeader>\n  \u003CCardBody>Content\u003C\u002FCardBody>\n\u003C\u002FCard>\n```\n\n### Compound Components\n\n```typescript\ninterface TabsContextValue {\n  activeTab: string\n  setActiveTab: (tab: string) => void\n}\n\nconst TabsContext = createContext\u003CTabsContextValue | undefined>(undefined)\n\nexport function Tabs({ children, defaultTab }: {\n  children: React.ReactNode\n  defaultTab: string\n}) {\n  const [activeTab, setActiveTab] = useState(defaultTab)\n\n  return (\n    \u003CTabsContext.Provider value={{ activeTab, setActiveTab }}>\n      {children}\n    \u003C\u002FTabsContext.Provider>\n  )\n}\n\nexport function TabList({ children }: { children: React.ReactNode }) {\n  return \u003Cdiv className=\"tab-list\">{children}\u003C\u002Fdiv>\n}\n\nexport function Tab({ id, children }: { id: string, children: React.ReactNode }) {\n  const context = useContext(TabsContext)\n  if (!context) throw new Error('Tab must be used within Tabs')\n\n  return (\n    \u003Cbutton\n      className={context.activeTab === id ? 'active' : ''}\n      onClick={() => context.setActiveTab(id)}\n    >\n      {children}\n    \u003C\u002Fbutton>\n  )\n}\n\n\u002F\u002F Usage\n\u003CTabs defaultTab=\"overview\">\n  \u003CTabList>\n    \u003CTab id=\"overview\">Overview\u003C\u002FTab>\n    \u003CTab id=\"details\">Details\u003C\u002FTab>\n  \u003C\u002FTabList>\n\u003C\u002FTabs>\n```\n\n### Render Props Pattern\n\n```typescript\ninterface DataLoaderProps\u003CT> {\n  url: string\n  children: (data: T | null, loading: boolean, error: Error | null) => React.ReactNode\n}\n\nexport function DataLoader\u003CT>({ url, children }: DataLoaderProps\u003CT>) {\n  const [data, setData] = useState\u003CT | null>(null)\n  const [loading, setLoading] = useState(true)\n  const [error, setError] = useState\u003CError | null>(null)\n\n  useEffect(() => {\n    fetch(url)\n      .then(res => res.json())\n      .then(setData)\n      .catch(setError)\n      .finally(() => setLoading(false))\n  }, [url])\n\n  return \u003C>{children(data, loading, error)}\u003C\u002F>\n}\n\n\u002F\u002F Usage\n\u003CDataLoader\u003CMarket[]> url=\"\u002Fapi\u002Fmarkets\">\n  {(markets, loading, error) => {\n    if (loading) return \u003CSpinner \u002F>\n    if (error) return \u003CError error={error} \u002F>\n    return \u003CMarketList markets={markets!} \u002F>\n  }}\n\u003C\u002FDataLoader>\n```\n\n## Custom Hooks Patterns\n\n### State Management Hook\n\n```typescript\nexport function useToggle(initialValue = false): [boolean, () => void] {\n  const [value, setValue] = useState(initialValue)\n\n  const toggle = useCallback(() => {\n    setValue(v => !v)\n  }, [])\n\n  return [value, toggle]\n}\n\n\u002F\u002F Usage\nconst [isOpen, toggleOpen] = useToggle()\n```\n\n### Async Data Fetching Hook\n\n```typescript\ninterface UseQueryOptions\u003CT> {\n  onSuccess?: (data: T) => void\n  onError?: (error: Error) => void\n  enabled?: boolean\n}\n\nexport function useQuery\u003CT>(\n  key: string,\n  fetcher: () => Promise\u003CT>,\n  options?: UseQueryOptions\u003CT>\n) {\n  const [data, setData] = useState\u003CT | null>(null)\n  const [error, setError] = useState\u003CError | null>(null)\n  const [loading, setLoading] = useState(false)\n\n  const refetch = useCallback(async () => {\n    setLoading(true)\n    setError(null)\n\n    try {\n      const result = await fetcher()\n      setData(result)\n      options?.onSuccess?.(result)\n    } catch (err) {\n      const error = err as Error\n      setError(error)\n      options?.onError?.(error)\n    } finally {\n      setLoading(false)\n    }\n  }, [fetcher, options])\n\n  useEffect(() => {\n    if (options?.enabled !== false) {\n      refetch()\n    }\n  }, [key, refetch, options?.enabled])\n\n  return { data, error, loading, refetch }\n}\n\n\u002F\u002F Usage\nconst { data: markets, loading, error, refetch } = useQuery(\n  'markets',\n  () => fetch('\u002Fapi\u002Fmarkets').then(r => r.json()),\n  {\n    onSuccess: data => console.log('Fetched', data.length, 'markets'),\n    onError: err => console.error('Failed:', err)\n  }\n)\n```\n\n### Debounce Hook\n\n```typescript\nexport function useDebounce\u003CT>(value: T, delay: number): T {\n  const [debouncedValue, setDebouncedValue] = useState\u003CT>(value)\n\n  useEffect(() => {\n    const handler = setTimeout(() => {\n      setDebouncedValue(value)\n    }, delay)\n\n    return () => clearTimeout(handler)\n  }, [value, delay])\n\n  return debouncedValue\n}\n\n\u002F\u002F Usage\nconst [searchQuery, setSearchQuery] = useState('')\nconst debouncedQuery = useDebounce(searchQuery, 500)\n\nuseEffect(() => {\n  if (debouncedQuery) {\n    performSearch(debouncedQuery)\n  }\n}, [debouncedQuery])\n```\n\n## State Management Patterns\n\n### Context + Reducer Pattern\n\n```typescript\ninterface State {\n  markets: Market[]\n  selectedMarket: Market | null\n  loading: boolean\n}\n\ntype Action =\n  | { type: 'SET_MARKETS'; payload: Market[] }\n  | { type: 'SELECT_MARKET'; payload: Market }\n  | { type: 'SET_LOADING'; payload: boolean }\n\nfunction reducer(state: State, action: Action): State {\n  switch (action.type) {\n    case 'SET_MARKETS':\n      return { ...state, markets: action.payload }\n    case 'SELECT_MARKET':\n      return { ...state, selectedMarket: action.payload }\n    case 'SET_LOADING':\n      return { ...state, loading: action.payload }\n    default:\n      return state\n  }\n}\n\nconst MarketContext = createContext\u003C{\n  state: State\n  dispatch: Dispatch\u003CAction>\n} | undefined>(undefined)\n\nexport function MarketProvider({ children }: { children: React.ReactNode }) {\n  const [state, dispatch] = useReducer(reducer, {\n    markets: [],\n    selectedMarket: null,\n    loading: false\n  })\n\n  return (\n    \u003CMarketContext.Provider value={{ state, dispatch }}>\n      {children}\n    \u003C\u002FMarketContext.Provider>\n  )\n}\n\nexport function useMarkets() {\n  const context = useContext(MarketContext)\n  if (!context) throw new Error('useMarkets must be used within MarketProvider')\n  return context\n}\n```\n\n## Performance Optimization\n\n### Memoization\n\n```typescript\n\u002F\u002F ✅ useMemo for expensive computations\nconst sortedMarkets = useMemo(() => {\n  return markets.sort((a, b) => b.volume - a.volume)\n}, [markets])\n\n\u002F\u002F ✅ useCallback for functions passed to children\nconst handleSearch = useCallback((query: string) => {\n  setSearchQuery(query)\n}, [])\n\n\u002F\u002F ✅ React.memo for pure components\nexport const MarketCard = React.memo\u003CMarketCardProps>(({ market }) => {\n  return (\n    \u003Cdiv className=\"market-card\">\n      \u003Ch3>{market.name}\u003C\u002Fh3>\n      \u003Cp>{market.description}\u003C\u002Fp>\n    \u003C\u002Fdiv>\n  )\n})\n```\n\n### Code Splitting & Lazy Loading\n\n```typescript\nimport { lazy, Suspense } from 'react'\n\n\u002F\u002F ✅ Lazy load heavy components\nconst HeavyChart = lazy(() => import('.\u002FHeavyChart'))\nconst ThreeJsBackground = lazy(() => import('.\u002FThreeJsBackground'))\n\nexport function Dashboard() {\n  return (\n    \u003Cdiv>\n      \u003CSuspense fallback={\u003CChartSkeleton \u002F>}>\n        \u003CHeavyChart data={data} \u002F>\n      \u003C\u002FSuspense>\n\n      \u003CSuspense fallback={null}>\n        \u003CThreeJsBackground \u002F>\n      \u003C\u002FSuspense>\n    \u003C\u002Fdiv>\n  )\n}\n```\n\n### Virtualization for Long Lists\n\n```typescript\nimport { useVirtualizer } from '@tanstack\u002Freact-virtual'\n\nexport function VirtualMarketList({ markets }: { markets: Market[] }) {\n  const parentRef = useRef\u003CHTMLDivElement>(null)\n\n  const virtualizer = useVirtualizer({\n    count: markets.length,\n    getScrollElement: () => parentRef.current,\n    estimateSize: () => 100,  \u002F\u002F Estimated row height\n    overscan: 5  \u002F\u002F Extra items to render\n  })\n\n  return (\n    \u003Cdiv ref={parentRef} style={{ height: '600px', overflow: 'auto' }}>\n      \u003Cdiv\n        style={{\n          height: `${virtualizer.getTotalSize()}px`,\n          position: 'relative'\n        }}\n      >\n        {virtualizer.getVirtualItems().map(virtualRow => (\n          \u003Cdiv\n            key={virtualRow.index}\n            style={{\n              position: 'absolute',\n              top: 0,\n              left: 0,\n              width: '100%',\n              height: `${virtualRow.size}px`,\n              transform: `translateY(${virtualRow.start}px)`\n            }}\n          >\n            \u003CMarketCard market={markets[virtualRow.index]} \u002F>\n          \u003C\u002Fdiv>\n        ))}\n      \u003C\u002Fdiv>\n    \u003C\u002Fdiv>\n  )\n}\n```\n\n## Form Handling Patterns\n\n### Controlled Form with Validation\n\n```typescript\ninterface FormData {\n  name: string\n  description: string\n  endDate: string\n}\n\ninterface FormErrors {\n  name?: string\n  description?: string\n  endDate?: string\n}\n\nexport function CreateMarketForm() {\n  const [formData, setFormData] = useState\u003CFormData>({\n    name: '',\n    description: '',\n    endDate: ''\n  })\n\n  const [errors, setErrors] = useState\u003CFormErrors>({})\n\n  const validate = (): boolean => {\n    const newErrors: FormErrors = {}\n\n    if (!formData.name.trim()) {\n      newErrors.name = 'Name is required'\n    } else if (formData.name.length > 200) {\n      newErrors.name = 'Name must be under 200 characters'\n    }\n\n    if (!formData.description.trim()) {\n      newErrors.description = 'Description is required'\n    }\n\n    if (!formData.endDate) {\n      newErrors.endDate = 'End date is required'\n    }\n\n    setErrors(newErrors)\n    return Object.keys(newErrors).length === 0\n  }\n\n  const handleSubmit = async (e: React.FormEvent) => {\n    e.preventDefault()\n\n    if (!validate()) return\n\n    try {\n      await createMarket(formData)\n      \u002F\u002F Success handling\n    } catch (error) {\n      \u002F\u002F Error handling\n    }\n  }\n\n  return (\n    \u003Cform onSubmit={handleSubmit}>\n      \u003Cinput\n        value={formData.name}\n        onChange={e => setFormData(prev => ({ ...prev, name: e.target.value }))}\n        placeholder=\"Market name\"\n      \u002F>\n      {errors.name && \u003Cspan className=\"error\">{errors.name}\u003C\u002Fspan>}\n\n      {\u002F* Other fields *\u002F}\n\n      \u003Cbutton type=\"submit\">Create Market\u003C\u002Fbutton>\n    \u003C\u002Fform>\n  )\n}\n```\n\n## Error Boundary Pattern\n\n```typescript\ninterface ErrorBoundaryState {\n  hasError: boolean\n  error: Error | null\n}\n\nexport class ErrorBoundary extends React.Component\u003C\n  { children: React.ReactNode },\n  ErrorBoundaryState\n> {\n  state: ErrorBoundaryState = {\n    hasError: false,\n    error: null\n  }\n\n  static getDerivedStateFromError(error: Error): ErrorBoundaryState {\n    return { hasError: true, error }\n  }\n\n  componentDidCatch(error: Error, errorInfo: React.ErrorInfo) {\n    console.error('Error boundary caught:', error, errorInfo)\n  }\n\n  render() {\n    if (this.state.hasError) {\n      return (\n        \u003Cdiv className=\"error-fallback\">\n          \u003Ch2>Something went wrong\u003C\u002Fh2>\n          \u003Cp>{this.state.error?.message}\u003C\u002Fp>\n          \u003Cbutton onClick={() => this.setState({ hasError: false })}>\n            Try again\n          \u003C\u002Fbutton>\n        \u003C\u002Fdiv>\n      )\n    }\n\n    return this.props.children\n  }\n}\n\n\u002F\u002F Usage\n\u003CErrorBoundary>\n  \u003CApp \u002F>\n\u003C\u002FErrorBoundary>\n```\n\n## Animation Patterns\n\n### Framer Motion Animations\n\n```typescript\nimport { motion, AnimatePresence } from 'framer-motion'\n\n\u002F\u002F ✅ List animations\nexport function AnimatedMarketList({ markets }: { markets: Market[] }) {\n  return (\n    \u003CAnimatePresence>\n      {markets.map(market => (\n        \u003Cmotion.div\n          key={market.id}\n          initial={{ opacity: 0, y: 20 }}\n          animate={{ opacity: 1, y: 0 }}\n          exit={{ opacity: 0, y: -20 }}\n          transition={{ duration: 0.3 }}\n        >\n          \u003CMarketCard market={market} \u002F>\n        \u003C\u002Fmotion.div>\n      ))}\n    \u003C\u002FAnimatePresence>\n  )\n}\n\n\u002F\u002F ✅ Modal animations\nexport function Modal({ isOpen, onClose, children }: ModalProps) {\n  return (\n    \u003CAnimatePresence>\n      {isOpen && (\n        \u003C>\n          \u003Cmotion.div\n            className=\"modal-overlay\"\n            initial={{ opacity: 0 }}\n            animate={{ opacity: 1 }}\n            exit={{ opacity: 0 }}\n            onClick={onClose}\n          \u002F>\n          \u003Cmotion.div\n            className=\"modal-content\"\n            initial={{ opacity: 0, scale: 0.9, y: 20 }}\n            animate={{ opacity: 1, scale: 1, y: 0 }}\n            exit={{ opacity: 0, scale: 0.9, y: 20 }}\n          >\n            {children}\n          \u003C\u002Fmotion.div>\n        \u003C\u002F>\n      )}\n    \u003C\u002FAnimatePresence>\n  )\n}\n```\n\n## Accessibility Patterns\n\n### Keyboard Navigation\n\n```typescript\nexport function Dropdown({ options, onSelect }: DropdownProps) {\n  const [isOpen, setIsOpen] = useState(false)\n  const [activeIndex, setActiveIndex] = useState(0)\n\n  const handleKeyDown = (e: React.KeyboardEvent) => {\n    switch (e.key) {\n      case 'ArrowDown':\n        e.preventDefault()\n        setActiveIndex(i => Math.min(i + 1, options.length - 1))\n        break\n      case 'ArrowUp':\n        e.preventDefault()\n        setActiveIndex(i => Math.max(i - 1, 0))\n        break\n      case 'Enter':\n        e.preventDefault()\n        onSelect(options[activeIndex])\n        setIsOpen(false)\n        break\n      case 'Escape':\n        setIsOpen(false)\n        break\n    }\n  }\n\n  return (\n    \u003Cdiv\n      role=\"combobox\"\n      aria-expanded={isOpen}\n      aria-haspopup=\"listbox\"\n      onKeyDown={handleKeyDown}\n    >\n      {\u002F* Dropdown implementation *\u002F}\n    \u003C\u002Fdiv>\n  )\n}\n```\n\n### Focus Management\n\n```typescript\nexport function Modal({ isOpen, onClose, children }: ModalProps) {\n  const modalRef = useRef\u003CHTMLDivElement>(null)\n  const previousFocusRef = useRef\u003CHTMLElement | null>(null)\n\n  useEffect(() => {\n    if (isOpen) {\n      \u002F\u002F Save currently focused element\n      previousFocusRef.current = document.activeElement as HTMLElement\n\n      \u002F\u002F Focus modal\n      modalRef.current?.focus()\n    } else {\n      \u002F\u002F Restore focus when closing\n      previousFocusRef.current?.focus()\n    }\n  }, [isOpen])\n\n  return isOpen ? (\n    \u003Cdiv\n      ref={modalRef}\n      role=\"dialog\"\n      aria-modal=\"true\"\n      tabIndex={-1}\n      onKeyDown={e => e.key === 'Escape' && onClose()}\n    >\n      {children}\n    \u003C\u002Fdiv>\n  ) : null\n}\n```\n\n**Remember**: Modern frontend patterns enable maintainable, performant user interfaces. Choose patterns that fit your project complexity.\n","# Frontend Development Patterns\n\nModern frontend patterns for React, Next.js, and performant user interfaces.\n\n## When to Activate\n\n- Building React components (composition, props, rendering)\n- Managing state (useState, useReducer, Zustand, Context)\n- Implementing data fetching (SWR, React Query, server components)\n- Optimizing performance (memoization, virtualization, code splitting)\n- Working with forms (validation, controlled inputs, Zod schemas)\n- Handling client-side routing and navigation\n- Building accessible, responsive UI patterns\n\n## Component Patterns\n\n### Composition Over Inheritance\n\n```typescript\n\u002F\u002F ✅ GOOD: Component composition\ninterface CardProps {\n  children: React.ReactNode\n  variant?: 'default' | 'outlined'\n}\n\nexport function Card({ children, variant = 'default' }: CardProps) {\n  return \u003Cdiv className={`card card-${variant}`}>{children}\u003C\u002Fdiv>\n}\n\nexport function CardHeader({ children }: { children: React.ReactNode }) {\n  return \u003Cdiv className=\"card-header\">{children}\u003C\u002Fdiv>\n}\n\nexport function CardBody({ children }: { children: React.ReactNode }) {\n  return \u003Cdiv className=\"card-body\">{children}\u003C\u002Fdiv>\n}\n\n\u002F\u002F Usage\n\u003CCard>\n  \u003CCardHeader>Title\u003C\u002FCardHeader>\n  \u003CCardBody>Content\u003C\u002FCardBody>\n\u003C\u002FCard>\n```\n\n### Compound Components\n\n```typescript\ninterface TabsContextValue {\n  activeTab: string\n  setActiveTab: (tab: string) => void\n}\n\nconst TabsContext = createContext\u003CTabsContextValue | undefined>(undefined)\n\nexport function Tabs({ children, defaultTab }: {\n  children: React.ReactNode\n  defaultTab: string\n}) {\n  const [activeTab, setActiveTab] = useState(defaultTab)\n\n  return (\n    \u003CTabsContext.Provider value={{ activeTab, setActiveTab }}>\n      {children}\n    \u003C\u002FTabsContext.Provider>\n  )\n}\n\nexport function TabList({ children }: { children: React.ReactNode }) {\n  return \u003Cdiv className=\"tab-list\">{children}\u003C\u002Fdiv>\n}\n\nexport function Tab({ id, children }: { id: string, children: React.ReactNode }) {\n  const context = useContext(TabsContext)\n  if (!context) throw new Error('Tab must be used within Tabs')\n\n  return (\n    \u003Cbutton\n      className={context.activeTab === id ? 'active' : ''}\n      onClick={() => context.setActiveTab(id)}\n    >\n      {children}\n    \u003C\u002Fbutton>\n  )\n}\n\n\u002F\u002F Usage\n\u003CTabs defaultTab=\"overview\">\n  \u003CTabList>\n    \u003CTab id=\"overview\">Overview\u003C\u002FTab>\n    \u003CTab id=\"details\">Details\u003C\u002FTab>\n  \u003C\u002FTabList>\n\u003C\u002FTabs>\n```\n\n### Render Props Pattern\n\n```typescript\ninterface DataLoaderProps\u003CT> {\n  url: string\n  children: (data: T | null, loading: boolean, error: Error | null) => React.ReactNode\n}\n\nexport function DataLoader\u003CT>({ url, children }: DataLoaderProps\u003CT>) {\n  const [data, setData] = useState\u003CT | null>(null)\n  const [loading, setLoading] = useState(true)\n  const [error, setError] = useState\u003CError | null>(null)\n\n  useEffect(() => {\n    fetch(url)\n      .then(res => res.json())\n      .then(setData)\n      .catch(setError)\n      .finally(() => setLoading(false))\n  }, [url])\n\n  return \u003C>{children(data, loading, error)}\u003C\u002F>\n}\n\n\u002F\u002F Usage\n\u003CDataLoader\u003CMarket[]> url=\"\u002Fapi\u002Fmarkets\">\n  {(markets, loading, error) => {\n    if (loading) return \u003CSpinner \u002F>\n    if (error) return \u003CError error={error} \u002F>\n    return \u003CMarketList markets={markets!} \u002F>\n  }}\n\u003C\u002FDataLoader>\n```\n\n## Custom Hooks Patterns\n\n### State Management Hook\n\n```typescript\nexport function useToggle(initialValue = false): [boolean, () => void] {\n  const [value, setValue] = useState(initialValue)\n\n  const toggle = useCallback(() => {\n    setValue(v => !v)\n  }, [])\n\n  return [value, toggle]\n}\n\n\u002F\u002F Usage\nconst [isOpen, toggleOpen] = useToggle()\n```\n\n### Async Data Fetching Hook\n\n```typescript\ninterface UseQueryOptions\u003CT> {\n  onSuccess?: (data: T) => void\n  onError?: (error: Error) => void\n  enabled?: boolean\n}\n\nexport function useQuery\u003CT>(\n  key: string,\n  fetcher: () => Promise\u003CT>,\n  options?: UseQueryOptions\u003CT>\n) {\n  const [data, setData] = useState\u003CT | null>(null)\n  const [error, setError] = useState\u003CError | null>(null)\n  const [loading, setLoading] = useState(false)\n\n  const refetch = useCallback(async () => {\n    setLoading(true)\n    setError(null)\n\n    try {\n      const result = await fetcher()\n      setData(result)\n      options?.onSuccess?.(result)\n    } catch (err) {\n      const error = err as Error\n      setError(error)\n      options?.onError?.(error)\n    } finally {\n      setLoading(false)\n    }\n  }, [fetcher, options])\n\n  useEffect(() => {\n    if (options?.enabled !== false) {\n      refetch()\n    }\n  }, [key, refetch, options?.enabled])\n\n  return { data, error, loading, refetch }\n}\n\n\u002F\u002F Usage\nconst { data: markets, loading, error, refetch } = useQuery(\n  'markets',\n  () => fetch('\u002Fapi\u002Fmarkets').then(r => r.json()),\n  {\n    onSuccess: data => console.log('Fetched', data.length, 'markets'),\n    onError: err => console.error('Failed:', err)\n  }\n)\n```\n\n### Debounce Hook\n\n```typescript\nexport function useDebounce\u003CT>(value: T, delay: number): T {\n  const [debouncedValue, setDebouncedValue] = useState\u003CT>(value)\n\n  useEffect(() => {\n    const handler = setTimeout(() => {\n      setDebouncedValue(value)\n    }, delay)\n\n    return () => clearTimeout(handler)\n  }, [value, delay])\n\n  return debouncedValue\n}\n\n\u002F\u002F Usage\nconst [searchQuery, setSearchQuery] = useState('')\nconst debouncedQuery = useDebounce(searchQuery, 500)\n\nuseEffect(() => {\n  if (debouncedQuery) {\n    performSearch(debouncedQuery)\n  }\n}, [debouncedQuery])\n```\n\n## State Management Patterns\n\n### Context + Reducer Pattern\n\n```typescript\ninterface State {\n  markets: Market[]\n  selectedMarket: Market | null\n  loading: boolean\n}\n\ntype Action =\n  | { type: 'SET_MARKETS'; payload: Market[] }\n  | { type: 'SELECT_MARKET'; payload: Market }\n  | { type: 'SET_LOADING'; payload: boolean }\n\nfunction reducer(state: State, action: Action): State {\n  switch (action.type) {\n    case 'SET_MARKETS':\n      return { ...state, markets: action.payload }\n    case 'SELECT_MARKET':\n      return { ...state, selectedMarket: action.payload }\n    case 'SET_LOADING':\n      return { ...state, loading: action.payload }\n    default:\n      return state\n  }\n}\n\nconst MarketContext = createContext\u003C{\n  state: State\n  dispatch: Dispatch\u003CAction>\n} | undefined>(undefined)\n\nexport function MarketProvider({ children }: { children: React.ReactNode }) {\n  const [state, dispatch] = useReducer(reducer, {\n    markets: [],\n    selectedMarket: null,\n    loading: false\n  })\n\n  return (\n    \u003CMarketContext.Provider value={{ state, dispatch }}>\n      {children}\n    \u003C\u002FMarketContext.Provider>\n  )\n}\n\nexport function useMarkets() {\n  const context = useContext(MarketContext)\n  if (!context) throw new Error('useMarkets must be used within MarketProvider')\n  return context\n}\n```\n\n## Performance Optimization\n\n### Memoization\n\n```typescript\n\u002F\u002F ✅ useMemo for expensive computations\nconst sortedMarkets = useMemo(() => {\n  return markets.sort((a, b) => b.volume - a.volume)\n}, [markets])\n\n\u002F\u002F ✅ useCallback for functions passed to children\nconst handleSearch = useCallback((query: string) => {\n  setSearchQuery(query)\n}, [])\n\n\u002F\u002F ✅ React.memo for pure components\nexport const MarketCard = React.memo\u003CMarketCardProps>(({ market }) => {\n  return (\n    \u003Cdiv className=\"market-card\">\n      \u003Ch3>{market.name}\u003C\u002Fh3>\n      \u003Cp>{market.description}\u003C\u002Fp>\n    \u003C\u002Fdiv>\n  )\n})\n```\n\n### Code Splitting & Lazy Loading\n\n```typescript\nimport { lazy, Suspense } from 'react'\n\n\u002F\u002F ✅ Lazy load heavy components\nconst HeavyChart = lazy(() => import('.\u002FHeavyChart'))\nconst ThreeJsBackground = lazy(() => import('.\u002FThreeJsBackground'))\n\nexport function Dashboard() {\n  return (\n    \u003Cdiv>\n      \u003CSuspense fallback={\u003CChartSkeleton \u002F>}>\n        \u003CHeavyChart data={data} \u002F>\n      \u003C\u002FSuspense>\n\n      \u003CSuspense fallback={null}>\n        \u003CThreeJsBackground \u002F>\n      \u003C\u002FSuspense>\n    \u003C\u002Fdiv>\n  )\n}\n```\n\n### Virtualization for Long Lists\n\n```typescript\nimport { useVirtualizer } from '@tanstack\u002Freact-virtual'\n\nexport function VirtualMarketList({ markets }: { markets: Market[] }) {\n  const parentRef = useRef\u003CHTMLDivElement>(null)\n\n  const virtualizer = useVirtualizer({\n    count: markets.length,\n    getScrollElement: () => parentRef.current,\n    estimateSize: () => 100,  \u002F\u002F Estimated row height\n    overscan: 5  \u002F\u002F Extra items to render\n  })\n\n  return (\n    \u003Cdiv ref={parentRef} style={{ height: '600px', overflow: 'auto' }}>\n      \u003Cdiv\n        style={{\n          height: `${virtualizer.getTotalSize()}px`,\n          position: 'relative'\n        }}\n      >\n        {virtualizer.getVirtualItems().map(virtualRow => (\n          \u003Cdiv\n            key={virtualRow.index}\n            style={{\n              position: 'absolute',\n              top: 0,\n              left: 0,\n              width: '100%',\n              height: `${virtualRow.size}px`,\n              transform: `translateY(${virtualRow.start}px)`\n            }}\n          >\n            \u003CMarketCard market={markets[virtualRow.index]} \u002F>\n          \u003C\u002Fdiv>\n        ))}\n      \u003C\u002Fdiv>\n    \u003C\u002Fdiv>\n  )\n}\n```\n\n## Form Handling Patterns\n\n### Controlled Form with Validation\n\n```typescript\ninterface FormData {\n  name: string\n  description: string\n  endDate: string\n}\n\ninterface FormErrors {\n  name?: string\n  description?: string\n  endDate?: string\n}\n\nexport function CreateMarketForm() {\n  const [formData, setFormData] = useState\u003CFormData>({\n    name: '',\n    description: '',\n    endDate: ''\n  })\n\n  const [errors, setErrors] = useState\u003CFormErrors>({})\n\n  const validate = (): boolean => {\n    const newErrors: FormErrors = {}\n\n    if (!formData.name.trim()) {\n      newErrors.name = 'Name is required'\n    } else if (formData.name.length > 200) {\n      newErrors.name = 'Name must be under 200 characters'\n    }\n\n    if (!formData.description.trim()) {\n      newErrors.description = 'Description is required'\n    }\n\n    if (!formData.endDate) {\n      newErrors.endDate = 'End date is required'\n    }\n\n    setErrors(newErrors)\n    return Object.keys(newErrors).length === 0\n  }\n\n  const handleSubmit = async (e: React.FormEvent) => {\n    e.preventDefault()\n\n    if (!validate()) return\n\n    try {\n      await createMarket(formData)\n      \u002F\u002F Success handling\n    } catch (error) {\n      \u002F\u002F Error handling\n    }\n  }\n\n  return (\n    \u003Cform onSubmit={handleSubmit}>\n      \u003Cinput\n        value={formData.name}\n        onChange={e => setFormData(prev => ({ ...prev, name: e.target.value }))}\n        placeholder=\"Market name\"\n      \u002F>\n      {errors.name && \u003Cspan className=\"error\">{errors.name}\u003C\u002Fspan>}\n\n      {\u002F* Other fields *\u002F}\n\n      \u003Cbutton type=\"submit\">Create Market\u003C\u002Fbutton>\n    \u003C\u002Fform>\n  )\n}\n```\n\n## Error Boundary Pattern\n\n```typescript\ninterface ErrorBoundaryState {\n  hasError: boolean\n  error: Error | null\n}\n\nexport class ErrorBoundary extends React.Component\u003C\n  { children: React.ReactNode },\n  ErrorBoundaryState\n> {\n  state: ErrorBoundaryState = {\n    hasError: false,\n    error: null\n  }\n\n  static getDerivedStateFromError(error: Error): ErrorBoundaryState {\n    return { hasError: true, error }\n  }\n\n  componentDidCatch(error: Error, errorInfo: React.ErrorInfo) {\n    console.error('Error boundary caught:', error, errorInfo)\n  }\n\n  render() {\n    if (this.state.hasError) {\n      return (\n        \u003Cdiv className=\"error-fallback\">\n          \u003Ch2>Something went wrong\u003C\u002Fh2>\n          \u003Cp>{this.state.error?.message}\u003C\u002Fp>\n          \u003Cbutton onClick={() => this.setState({ hasError: false })}>\n            Try again\n          \u003C\u002Fbutton>\n        \u003C\u002Fdiv>\n      )\n    }\n\n    return this.props.children\n  }\n}\n\n\u002F\u002F Usage\n\u003CErrorBoundary>\n  \u003CApp \u002F>\n\u003C\u002FErrorBoundary>\n```\n\n## Animation Patterns\n\n### Framer Motion Animations\n\n```typescript\nimport { motion, AnimatePresence } from 'framer-motion'\n\n\u002F\u002F ✅ List animations\nexport function AnimatedMarketList({ markets }: { markets: Market[] }) {\n  return (\n    \u003CAnimatePresence>\n      {markets.map(market => (\n        \u003Cmotion.div\n          key={market.id}\n          initial={{ opacity: 0, y: 20 }}\n          animate={{ opacity: 1, y: 0 }}\n          exit={{ opacity: 0, y: -20 }}\n          transition={{ duration: 0.3 }}\n        >\n          \u003CMarketCard market={market} \u002F>\n        \u003C\u002Fmotion.div>\n      ))}\n    \u003C\u002FAnimatePresence>\n  )\n}\n\n\u002F\u002F ✅ Modal animations\nexport function Modal({ isOpen, onClose, children }: ModalProps) {\n  return (\n    \u003CAnimatePresence>\n      {isOpen && (\n        \u003C>\n          \u003Cmotion.div\n            className=\"modal-overlay\"\n            initial={{ opacity: 0 }}\n            animate={{ opacity: 1 }}\n            exit={{ opacity: 0 }}\n            onClick={onClose}\n          \u002F>\n          \u003Cmotion.div\n            className=\"modal-content\"\n            initial={{ opacity: 0, scale: 0.9, y: 20 }}\n            animate={{ opacity: 1, scale: 1, y: 0 }}\n            exit={{ opacity: 0, scale: 0.9, y: 20 }}\n          >\n            {children}\n          \u003C\u002Fmotion.div>\n        \u003C\u002F>\n      )}\n    \u003C\u002FAnimatePresence>\n  )\n}\n```\n\n## Accessibility Patterns\n\n### Keyboard Navigation\n\n```typescript\nexport function Dropdown({ options, onSelect }: DropdownProps) {\n  const [isOpen, setIsOpen] = useState(false)\n  const [activeIndex, setActiveIndex] = useState(0)\n\n  const handleKeyDown = (e: React.KeyboardEvent) => {\n    switch (e.key) {\n      case 'ArrowDown':\n        e.preventDefault()\n        setActiveIndex(i => Math.min(i + 1, options.length - 1))\n        break\n      case 'ArrowUp':\n        e.preventDefault()\n        setActiveIndex(i => Math.max(i - 1, 0))\n        break\n      case 'Enter':\n        e.preventDefault()\n        onSelect(options[activeIndex])\n        setIsOpen(false)\n        break\n      case 'Escape':\n        setIsOpen(false)\n        break\n    }\n  }\n\n  return (\n    \u003Cdiv\n      role=\"combobox\"\n      aria-expanded={isOpen}\n      aria-haspopup=\"listbox\"\n      onKeyDown={handleKeyDown}\n    >\n      {\u002F* Dropdown implementation *\u002F}\n    \u003C\u002Fdiv>\n  )\n}\n```\n\n### Focus Management\n\n```typescript\nexport function Modal({ isOpen, onClose, children }: ModalProps) {\n  const modalRef = useRef\u003CHTMLDivElement>(null)\n  const previousFocusRef = useRef\u003CHTMLElement | null>(null)\n\n  useEffect(() => {\n    if (isOpen) {\n      \u002F\u002F Save currently focused element\n      previousFocusRef.current = document.activeElement as HTMLElement\n\n      \u002F\u002F Focus modal\n      modalRef.current?.focus()\n    } else {\n      \u002F\u002F Restore focus when closing\n      previousFocusRef.current?.focus()\n    }\n  }, [isOpen])\n\n  return isOpen ? 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Choose patterns that fit your project complexity.\n",{"name":5,"origin":46,"description":7},"ECC","main","a318f48de3c5718e8ea2e9f6fae7790e8a759e85","upstream-sync\u002Fwork\u002Fecc\u002F.agents\u002Fskills\u002Ffrontend-patterns",0,"https:\u002F\u002Fgithub.com\u002Foabdelmaksoud\u002FAgention","https:\u002F\u002Fgithub.com\u002Foabdelmaksoud","https:\u002F\u002Fwww.linkedin.com\u002Fin\u002Fo-abdelmaksoud\u002F","Full-Stack Engineer | AI Systems Architect | Building autonomous multi-agent systems","2026-03-08 21:23:03",{"source":8,"skillName":5,"commands":57,"prompt":67,"zipAvailable":68},[58,61,64],{"tool":59,"command":60},"npx","npx skills add oabdelmaksoud\u002FAgention --skill frontend-patterns",{"tool":62,"command":63},"bunx","bunx skills add oabdelmaksoud\u002FAgention --skill frontend-patterns",{"tool":65,"command":66},"pnpm","pnpm dlx skills add oabdelmaksoud\u002FAgention --skill frontend-patterns","安装技能，技能地址：https:\u002F\u002Fgithub.com\u002Foabdelmaksoud\u002FAgention\u002Fblob\u002Fmain\u002Fupstream-sync\u002Fwork\u002Fecc\u002F.agents\u002Fskills\u002Ffrontend-patterns\u002FSKILL.md",true,[70],{"path":71,"resourceType":72,"resourceTypeDesc":73,"sizeBytes":74,"sourceHtmlUrl":75},"agents\u002Fopenai.yaml","REFERENCE","参考文档",251,"https:\u002F\u002Fgithub.com\u002Foabdelmaksoud\u002FAgention\u002Fblob\u002Fmain\u002Fupstream-sync\u002Fwork\u002Fecc\u002F.agents\u002Fskills\u002Ffrontend-patterns\u002Fagents\u002Fopenai.yaml",[77,99,113,145,162,182],{"skillNo":78,"name":79,"nameZh":6,"description":80,"descriptionZh":6,"repositoryFullName":8,"ownerLogin":9,"ownerAvatarUrl":10,"ownerAccountNo":11,"ownerDisplayName":12,"repositoryNo":13,"starsCount":14,"licenseSpdxId":15,"licenseFileUrl":6,"sourceHtmlUrl":81,"categories":82,"keywords":86,"publishedAt":41},"01M6G2QFCBNBYAJF2KTK85G9A6","visa-doc-translate","Translate visa application documents (images) to English and create a bilingual PDF with original and translation","https:\u002F\u002Fgithub.com\u002Foabdelmaksoud\u002FAgention\u002Fblob\u002Fmain\u002Fupstream-sync\u002Fwork\u002Fecc\u002Fskills\u002Fvisa-doc-translate\u002FSKILL.md",[83],{"categoryNo":84,"categoryName":85,"taxonomyType":21,"taxonomyTypeDesc":22},"01JBSEEDCAT000000000000002","文档处理",[87,88,89,90,91,92,93,94,95,96,97,98],"translate","doc","visa doc translate","bilingual","with","english","application","PDF","translation","documents","create","images",{"skillNo":100,"name":101,"nameZh":6,"description":102,"descriptionZh":6,"repositoryFullName":8,"ownerLogin":9,"ownerAvatarUrl":10,"ownerAccountNo":11,"ownerDisplayName":12,"repositoryNo":13,"starsCount":14,"licenseSpdxId":15,"licenseFileUrl":6,"sourceHtmlUrl":103,"categories":104,"keywords":105,"publishedAt":41},"01M6G2QB09TSK6BY4ME5X20EVQ","verification-loop","A comprehensive verification system for Claude Code sessions.","https:\u002F\u002Fgithub.com\u002Foabdelmaksoud\u002FAgention\u002Fblob\u002Fmain\u002Fupstream-sync\u002Fwork\u002Fecc\u002Fskills\u002Fverification-loop\u002FSKILL.md",[],[106,107,108,109,110,111,112],"verification","loop","verification loop","sessions","code","claude code sessions","system",{"skillNo":114,"name":115,"nameZh":6,"description":116,"descriptionZh":6,"repositoryFullName":8,"ownerLogin":9,"ownerAvatarUrl":10,"ownerAccountNo":11,"ownerDisplayName":12,"repositoryNo":13,"starsCount":14,"licenseSpdxId":15,"licenseFileUrl":6,"sourceHtmlUrl":117,"categories":118,"keywords":130,"publishedAt":41},"01M6G2Q6V2F7G03VAAF27FXPJR","tdd-workflow","Use this skill when writing new features, fixing bugs, or refactoring code. 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