React Form Handling with useReducer and Async Validation - State implementation guide Correctly
I've been banging my head against this for hours. I've searched everywhere and can't find a clear answer. I'm working with an scenario with my React functional component where I'm using `useReducer` for form state management and trying to implement async validation on one of the fields. The question arises when the async validation function is called; the state for that specific field does not seem to update correctly before the validation result is returned. Here’s a simplified version of my code: ```javascript import React, { useReducer } from 'react'; const initialState = { username: '', behavior: '' }; function reducer(state, action) { switch (action.type) { case 'SET_USERNAME': return { ...state, username: action.payload, behavior: '' }; case 'SET_ERROR': return { ...state, behavior: action.payload }; default: return state; } } const asyncValidateUsername = async (username) => { // Simulate an API call return new Promise((resolve) => { setTimeout(() => { if (username === 'admin') { resolve('Username not available'); } else { resolve(''); } }, 1000); }); }; const MyForm = () => { const [state, dispatch] = useReducer(reducer, initialState); const handleChange = async (e) => { const { value } = e.target; dispatch({ type: 'SET_USERNAME', payload: value }); const validationError = await asyncValidateUsername(value); if (validationError) { dispatch({ type: 'SET_ERROR', payload: validationError }); } }; return ( <form> <input type="text" value={state.username} onChange={handleChange} /> {state.behavior && <span>{state.behavior}</span>} <button type="submit">Submit</button> </form> ); }; export default MyForm; ``` I've tried using `async` and `await` in the `handleChange` function, but when I type in the input field, the behavior message does not show up immediately if the username is invalid (e.g., "admin"). Instead, it updates only after I click away from the input field. The behavior message seems to be delayed, and it’s confusing for users. Is there a better way to handle this scenario? I want the behavior to display as soon as the validation results come back, ideally without any lag. I'm using React version 17.0.2 and I’m not sure if this behavior is expected. Any advice on improving the user experience would be appreciated! I'm working on a application that needs to handle this. How would you solve this? For context: I'm using Javascript on Windows 10.