react-native run-android is giving error undefined is not a function (evaluating 'react DevTools.connect DevTools')

[ghost]

Environment

React Native Environment Info:
System:
OS: Windows 10
CPU: (4) x64 Intel(R) Core(TM) i3-7100 CPU @ 3.90GHz
Memory: 1.44 GB / 7.91 GB
Binaries:
Yarn: 1.9.4 - C:\Users\Yajana\AppData\Roaming\npm\yarn.CMD
npm: 6.4.1 - C:\Program Files\nodejs\npm.CMD
Watchman: 4.9.0 - C:\Shortcut\watchman.EXE
IDEs:
Android Studio: Version 3.0.0.0 AI-171.4443003

Description

Getting error as
undefined is not a function (evaluating 'reactDevTools.connectToDevTools')

C:\Users\Yajana\React-Native\fr-react-native\FrReactNative\node_modules\react-native\Libraries\Core\Devtools\setupDevtools.js:50:36
loadModuleImplementation
C:\Users\Yajana\React-Native\fr-react-native\FrReactNative\node_modules\metro\src\lib\polyfills\require.js:320:6
guardedLoadModule
C:\Users\Yajana\React-Native\fr-react-native\FrReactNative\node_modules\metro\src\lib\polyfills\require.js:214:36
metroRequire
C:\Users\Yajana\React-Native\fr-react-native\FrReactNative\node_modules\metro\src\lib\polyfills\require.js:136:24

C:\Users\Yajana\React-Native\fr-react-native\FrReactNative\node_modules\react-native\Libraries\Core\InitializeCore.js:211:13
loadModuleImplementation
C:\Users\Yajana\React-Native\fr-react-native\FrReactNative\node_modules\metro\src\lib\polyfills\require.js:320:6
guardedLoadModule
C:\Users\Yajana\React-Native\fr-react-native\FrReactNative\node_modules\metro\src\lib\polyfills\require.js:207:45
metroRequire
C:\Users\Yajana\React-Native\fr-react-native\FrReactNative\node_modules\metro\src\lib\polyfills\require.js:136:24
global code

[TheSixer]

+1

[ieniegg]

+1

[aathapa]

#22863

[thaopit1992]

run after when create project
yarn add eslint-config-rallycoding --dev

[bbeckk]

+1

[Xifeat]

+1

[antoniomarcosferreira]

Thanks, @Aayush-dev, #22863 This work for me!

[decisionnguyen]

+1

[ghost]

npm install --save-dev [email protected] Resolved the issue

[razerduy]

{
"name": "JWallet",
"version": "0.0.1",
"private": true,
"scripts": {
"start": "node node_modules/react-native/local-cli/cli.js start",
"test": "jest",
"i": "rm -rf node_modules yarn.lock && yarn install",
"run:devTools": "react-devtools",
"bundle:ios": "rm -rf ./ios/REPatient/main.jsbundle && react-native bundle --entry-file='index.js' --bundle-output='./ios/JWallet/main.jsbundle' --dev=false --platform='ios' --assets-dest='./ios'",
"run:ios": "react-native run-ios"
},
"dependencies": {
"react": "16.6.3",
"react-native": "0.57.8"
},
"devDependencies": {
"babel-jest": "23.6.0",
"eslint-config-rallycoding": "^3.2.0",
"jest": "23.6.0",
"metro-react-native-babel-preset": "0.51.1",
"react-devtools-core": "3.4.2",
"react-test-renderer": "16.6.3"
},
"jest": {
"preset": "react-native"
}
}

Still error

[shravanteegala]

i resolved using below command
npm install --save-dev [email protected] Resolved the issue

[gabryelferreira]

+1

[bhavu43]

npm install --save-dev [email protected] → Works

[akiladevinda]

This will work
npm install --save-dev [email protected]

or try to remove node_modules folder and re-install it using 'npm install --save'

[charlesnse]

npm install --save-dev [email protected]

then also run react-native run-android

works perfectly for me

[tomm1996]

Can anyone explain why installing react-devtools-core will fix the issue?

[sachinkodkani]

thanks @yajan
installation of react devtools core solved my issue!

[jasonroyle]

Can anyone explain why installing react-devtools-core will fix the issue?

More info at #22863

[tpmpb]

npm install --save-dev [email protected] Resolved the issue

Unfortunately didn't work :'(

[jasonroyle]

I am running...

react-native: 0.57.8
react-native-cli: 2.0.1
yarn: 1.12.3

I needed to add a resolution to package.json...

{
  ...
  "resolutions": {
    "react-devtools-core": "3.4.3"
  }
}

Then run...

$ yarn
$ yarn start --reset-cache

[atrauzzi]

If you're running the current version of react-native, react-devtools-core 3.5.x is a transitive dependency and as a result npm/yarn install will result in react-native having its own copy at that version. Even despite whether you specify 3.4.x in your own package.json.

If you're using yarn, you can tell it to flatten your dependency tree and then manually force it to resolve the older version for the single copy it installs.

Be warned, this is also going to result in it prompting you for every shared dependency in your project, although personally, I like this for several reasons... ☺️

[danielfssz]

+1

[danielfssz]

i resolved using below command
npm install --save-dev [email protected] Resolved the issue

• npm install

solved for me

[tpmpb]

I am running...

react-native: 0.57.8
react-native-cli: 2.0.1
yarn: 1.12.3

I needed to add a resolution to package.json...

{
  ...
  "resolutions": {
    "react-devtools-core": "3.4.3"
  }
}

Then run...

$ yarn
$ yarn start --reset-cache

THAAANK YOU, BUDDY