React

1. 1

   What is React?

   What React isComponents as functionsVirtual DOM intuitionRendering JSXCreating a Vite app
   25 min
2. 2

   JSX and Components

   JSX syntax rulesSingle root elementClassName vs classEmbedding expressions with {}Defining componentsComposing components
   30 min
3. 3

   Props

   Passing props as attributesReceiving props objectDestructuring props in signatureDefault valuesThinking about prop shapes
   30 min
4. 4

   State with useState

   UseState hookReading stateCalling the setterUpdater function formNever mutate stateCounter pattern
   35 min
5. 5

   Handling Events

   OnClick handlerOnChange basicsPassing functions vs calling themEvent objectPassing handlers as props
   30 min
6. 6

   Conditional Rendering and Lists

   && for show/hideTernary for either/orMapping arrays to JSXThe key propWhy keys need to be stable
   30 min
7. 7

   Forms and Controlled Inputs

   Controlled input patternValue and onChange togetherMulti-field form stateOnSubmit and preventDefaultGathering form data
   35 min
8. 8

   Effects with useEffect

   What counts as a side effectUseEffect signatureDependency arrayRunning on mount onlyCleanup functionSubscribe/unsubscribe pattern
   40 min
9. 9

   Component Composition

   Children propWrapping componentsPassing JSX as propsLifting state upThinking in component trees
   35 min
10. 10

    Context and useContext

    CreateContextContext.ProviderUseContextWhen context is the right toolContext vs prop drilling tradeoffs
    35 min
11. 11

    useReducer

    When to reach for useReducerReducer function shapeAction objectsDispatchCombining useReducer with useContext
    35 min
12. 12

    Custom Hooks

    Extracting stateful logic into a functionUse prefix conventionUseToggle exampleUseLocalStorage exampleHooks rules
    35 min
13. 13

    Performance and Memoization

    React.memo for componentsUseMemo for expensive computationsUseCallback for stable function referencesWhen memoization is overkillMeasuring before optimizing
    35 min
14. 14

    Data Fetching

    Fetch inside useEffectLoading/error/data statesAbortController cleanupPreventing setState after unmountMention TanStack Query as a next step
    40 min
15. 15

    Routing with React Router

    Installing react-router-domBrowserRouterRoutes and RouteLink for navigationUseParamsUseNavigate
    40 min
16. 16

    Testing React Components

    Vitest + React Testing Library setupRender and screenGetByRole queriesUserEvent for interactionsWriting one good button test
    40 min
17. 17

    Capstone: Todo App

    Combining state, lists, controlled inputsCustom hook for localStorage persistenceSmall routing setupPutting it together
    60 min

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