👀 Views: 69 💬 Answers: 1 📅 Created: 2025-06-27

reactjs usecontext usereducer javascript

I'm building a feature where I'm currently working on a React 18 application where I'm trying to manage state using `useContext` in combination with `useReducer`. The goal is to have a global state that multiple nested components can access and update. However, I'm encountering unexpected behavior when trying to update the state from a deeply nested component. Here's a simplified version of my context and reducer setup: ```javascript import React, { createContext, useReducer, useContext } from 'react'; const initialState = { count: 0 }; const CountContext = createContext(); const countReducer = (state, action) => { switch (action.type) { case 'increment': return { count: state.count + 1 }; case 'decrement': return { count: state.count - 1 }; default: return state; } }; export const CountProvider = ({ children }) => { const [state, dispatch] = useReducer(countReducer, initialState); return ( <CountContext.Provider value={{ state, dispatch }}> {children} </CountContext.Provider> ); }; export const useCount = () => useContext(CountContext); ``` I wrapped my main application component with `CountProvider` to make the context available. In a nested component, I'm trying to update the count like this: ```javascript import React from 'react'; import { useCount } from './CountContext'; const NestedComponent = () => { const { state, dispatch } = useCount(); const handleIncrement = () => { dispatch({ type: 'increment' }); }; return ( <div> <p>Count: {state.count}</p> <button onClick={handleIncrement}>Increment</button> </div> ); }; export default NestedComponent; ``` The problem arises when I click on the 'Increment' button. The count updates correctly, but after the first increment, it seems like the component does not re-render as expected. I checked the value of `state.count` and it reflects the updated value, but the UI doesn't reflect this change. I have also verified that there are no memoized components that could be preventing updates. I've tried using `React.memo` on the component, but it doesn't seem to solve the issue. Additionally, I have confirmed that the `dispatch` function is being called correctly by logging the actions. I would appreciate any insights on what could be causing this issue or if there's a best practice I might be overlooking. What are your experiences with this?