React Native项目（Expo模拟器）报错求助：Cannot read property 'func' of undefined

Hey there, let's walk through how to dig into this error you're facing. First, let's clarify that node_modules/react-native/ExceptionsManager.js is just React Native's built-in error handler—it catches and displays errors, but it's not the source of your problem. The real issue lives in your project code or dependency setup. Here's a step-by-step troubleshooting plan:

1. Dig into the full error stack traces #

You mentioned there are 2 related errors—don't stop at the line pointing to ExceptionsManager.js. Look for entries in the stack trace that reference files in your own project (e.g., paths starting with ./src/, ./components/, or your project root). Those lines will tell you exactly which part of your code is triggering the error.

2. Check your PropTypes usage #

The 'func' property in the error almost always ties to PropTypes validation. React Native no longer includes PropTypes by default, so:

• Make sure you've installed the standalone prop-types package:

  npm install prop-types
  # or
  yarn add prop-types
  

• Verify you're importing it correctly in your components:

  // Correct
  import PropTypes from 'prop-types';
  
  // Wrong (this is deprecated and will throw errors)
  import React from 'react';
  const PropTypes = React.PropTypes;
  

• Double-check that any component expecting a function prop (e.g., an onPress handler) has valid PropTypes defined, and that you're actually passing that prop from the parent component.

3. Audit recent code changes #

Think about what you added or modified right before the error started happening:

• Did you create a new component that expects a function prop but isn't receiving it?
• Did you refactor a function and accidentally make its parent object undefined (e.g., forgetting to bind this in a class component, or using an uninitialized variable before assigning it)?
• Are you trying to access a func property on a variable that's undefined (e.g., someUndefinedVar.func())?

4. Validate dependency compatibility #

Expo and React Native have strict version compatibility rules. Run this command to check for mismatched dependencies:

expo doctor

This will flag any packages that are incompatible with your current Expo SDK version. Pay extra attention to third-party UI libraries or state management tools—outdated versions often have broken PropTypes implementations.

5. Clear cached data #

Cached artifacts can sometimes cause weird, hard-to-track errors. Try these steps:

• Reset Expo's cache and restart your project:

  expo r -c
  

• If that doesn't work, wipe your node_modules and reinstall dependencies:

  rm -rf node_modules package-lock.json yarn.lock
  npm install
  # or
  yarn install
  

6. Isolate the issue with a minimal test #

If you're still stuck, create a brand new Expo project and gradually add pieces of your code (components, hooks, dependencies) until the error reappears. This will help you pinpoint exactly which part of your project is causing the problem.

内容的提问来源于stack exchange，提问作者Tim