Yaushe za ka yi amfani da useReducer maimakon useState?

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`useReducer` tasa da transitions na state a wata **gida reducer function** gida, maimakon katanga setters na `useState` da yawa. Shi shine nau'i na Redux pattern na React. ```jsx function reducer(state, action) { switch (action.type) { case "increment": return { count: state.count + 1 }; case "setStep": return { ...state, step: action.payload }; case "reset": return { count: 0, step: 1 }; default: return state; } } function Counter() { const [state, dispatch] = useReducer(reducer, { count: 0, step: 1 }); // describe WHAT happened, not HOW state changes: return ; } ``` ## Yadda yake aiki Ka **aika** wata **action** (wani abu mai saufu da ke ba da codon na abin da ya faru). React tasa ga `reducer(currentState, action)` kuma tasa da object din kawo a matsayin sabon state. Reducer shine **tsarki** (babu alamomi na gefen, babu canji), wanda ke sa logicin jiya da kuma bubugi na unit-test a kira. ## Lokacin da za ka fi so shi a wannan useState - State na gida **ya dogara da state na jiya** a wata hanya da ba ta sauwa. - Dama da yawa **suna canja tare** (mis. `count` + `step` + `error`). - Logic na sabili na hadarin da zai yi maidowa shi a cikin handlers daban-daban. ```jsx // instead of 4 separate useState + 6 setters, one reducer owns it all ``` Bonus: `dispatch` yana da **mutum-gida kakaure**, saboda haka gabatar da shi ta cikin context ko ga yara na alade baba bayi ba sabani ba. Don sauƙake, independuntansa ƙa, zalka `useState` har yanzu fiye da dacewa.