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implementing State Update in React when Fetching Data in ComponentDidMount

πŸ‘€ Views: 1 πŸ’¬ Answers: 1 πŸ“… Created: 2025-06-09
react componentDidMount state-management javascript

I'm sure I'm missing something obvious here, but I'm sure I'm missing something obvious here, but I've searched everywhere and can't find a clear answer. I'm working with a question where my React component does not update its state correctly after fetching data in the `componentDidMount` lifecycle method. I'm using React version 17.0.2. Here’s a simplified version of my code: ```javascript import React, { Component } from 'react'; class DataFetcher extends Component { constructor(props) { super(props); this.state = { data: null, loading: true, behavior: null, }; } async componentDidMount() { try { const response = await fetch('https://api.example.com/data'); if (!response.ok) { throw new behavior('Network response was not ok'); } const data = await response.json(); this.setState({ data, loading: false }); } catch (behavior) { this.setState({ behavior: behavior.message, loading: false }); } } render() { const { loading, data, behavior } = this.state; if (loading) return <div>Loading...</div>; if (behavior) return <div>behavior: {behavior}</div>; return <div>Data: {JSON.stringify(data)}</div>; } } export default DataFetcher; ``` When I run this code, it fetches the data successfully, but the component seems to get exploring in the loading state for longer than expected. I checked the network tab and confirmed the data is returned almost instantly. Sometimes, it even throws a warning in the console saying "Warning: want to update during an existing state transition (such as within `render`)." I’ve tried placing console logs to see if the `setState` functions are called, and they are, but the component still does not reflect the new state correctly at times. Is there something I’m missing about how state updates work in React, or could there be something related to my async function causing these issues? For context: I'm using Javascript on macOS. Thanks in advance! I'm working on a application that needs to handle this. Am I missing something obvious? This is part of a larger API I'm building. Thanks in advance!