React app crashing on state update during asynchronous operation - Error: Cannot read property 'setState' of null
I'm wondering if anyone has experience with I'm testing a new approach and I've searched everywhere and can't find a clear answer. I'm stuck on something that should probably be simple. Hey everyone, I'm running into an issue that's driving me crazy. While developing a React application for my startup’s MVP, I’ve run into a frustrating issue that’s causing the app to crash intermittently. I have a component that fetches user data from an API, and I’m using the `async/await` syntax to handle the asynchronous call. The problem arises when I attempt to update the state after receiving the data. Occasionally, I get the error: `Error: Cannot read property 'setState' of null`. Here’s a simplified version of my code: ```javascript class UserProfile extends React.Component { state = { user: null, loading: true, }; async componentDidMount() { try { const response = await fetch('https://api.example.com/user'); const data = await response.json(); this.setState({ user: data, loading: false }); } catch (error) { console.error('Error fetching user data:', error); this.setState({ loading: false }); } } render() { const { user, loading } = this.state; if (loading) return <div>Loading...</div>; return <div>{user.name}</div>; } } ``` I suspect the issue is related to the component unmounting before the data fetch completes, which would leave `this` undefined when `setState` is called. To address this, I tried wrapping the `setState` calls in a check to see if the component is still mounted, but I’ve been struggling to implement that correctly. Any suggestions on how to safely handle the state update or a different approach to manage this kind of behavior? I’m using React 17.0.2 and this behavior seems to occur sporadically. Would love to hear how others have approached similar issues. My development environment is Windows. How would you solve this? My development environment is Ubuntu. Am I missing something obvious? I'm developing on Linux with Javascript. Thanks in advance! Any ideas how to fix this?