Troubleshooting and Debugging React Native
console.log
Enable console.log
s for React Native
# run this command (when the app is running) to enable React Native logging
# You only need to run this once and it'll be enabled for all future apps as well
npx react-native log-ios
npx react-native log-android
adb logs
You can start adb
logging in another Terminal window
# For a steady stream of constant logging
adb logcat
# filter React related logs
adb logcat '*:S ReactNative:V ReactNativeJS:V'
Common Errors
White screen of death
You get an empty blank screen and no errors..
Chances are you ran react-native run-android
first and then react-native start
.
What you gotta do is close the app. Run react-native start
and then in another terminal, run react-native run-android
. You have to run react-native run-android
in a separate terminal because you don't get the prompt back when running react-native start
Could not connect to development server 500 -OR- SHA-1 ReferenceError
The development server returned response error code: 500
error: ReferenceError: SHA-1 for file node/v12.18.0/lib/node_modules/react-native/node_modules/metro/src/lib/polyfills/require.js (node/v12.18.0/lib/node_modules/react-native/node_modules/metro/src/lib/polyfills/require.js) is not computed
Turns out i had react-native
insatlled globally instead of react-native-cli
. If you have both react-native
and react-native-cli
installed, it'll be messed up..
Solution is simple
npm uninstall -g react-native
npm i -g react-native-cli
# OR
yarn global remove react-native
yarn global add react-native-cli
Or just use npx
.