React native start error

Comments

Summary:
**Summary**

On Windows with Node.js v12.x.x, Metro crashes with
```
SyntaxError: Invalid regular expression: /(.*\__fixtures__\.*|node_modules[\]react[\]dist[\].*|website\node_modules\.*|heapCapture\bundle.js|.*\__tests__\.*)$/: Unterminated character class
```
This has been reported in #453, facebook/react-native#26829, facebook/react-native#26969, facebook/react-native#26878, facebook/react-native#26598, expo/expo-cli#1147 and expo/expo-cli#1074.

There are a few open pull requests attempting to fix this same issue:
* #464
* #461
* #458
* #454

However, none of the existing PRs address the *root cause* of this error: the `escapeRegExp` function in `blacklist.js` tries to convert regular expressions to be agnostic to the path separator ("/" or "\"), but turns some valid regular expressions to invalid syntax.

The error was is this line:
https://github.com/facebook/metro/blob/142348f5345e40ce2075fc7f9dfa30c5d31fee2a/packages/metro-config/src/defaults/blacklist.js#L28
When given a regular expression, such as `/node_modules[/\]react[/\]dist[/\].*/`, on Windows where `path.sep` is `` (which is also an escape character in regular expressions), this gets turned into `/node_modules[\]react[\]dist[\].*/`, resulting in the `Unterminated character class` error.

Automatically replacing `[/]` with `[]` is an error, as is replacing `[/]` with `[\]`, because in both of these cases the backslash before the end of character class "]" escapes it, and the character class becomes unterminated. Therefore, this PR changes the code to look for both escaped forward slash `/` and forward slash `/`, and always replace them with the escaped version (`/` or `\`, depending on the platform).

This fixes #453.

**Test plan**

Added a test case that exercises the code with both `` and `/` as path separators.
Pull Request resolved: #468

Differential Revision: D18201730

Pulled By: cpojer

fbshipit-source-id: 6bb694178314c39d4d6a0fd9f8547bfa2c36f894

04 Jul 2017

• iOS errors
• Android errors
• JS errors
  • Couldn’t find preset “es2015”
  • React.Children.only expected to receive a single React element child
  • Maximum call stack size exceeded
  • In next release empty section headers will be rendered
  • onEndReached event of ListView keeps on firing
  • ListView becomes blank
  • SyntaxError wallet.png: Unexpected character (1:0)
  • Actions must be plain objects
  • TouchableOpacity ignores initial opacity
  • Unknown named module
  • ScrollView with unbounded height doesn’t grow on scrolling
  • TextInput inside TouchableOpacity intercepts touches
  • fontWeight={600} is not applied to TextInput
  • undefined is not an object (evaluating ‘Sentry.options.logLevel’)
  • ScrollView content is partially hidden below when scrolled to the bottom
  • ScrollView inside Modal doesn’t respect keyboardShouldPersistTaps='handled'
  • Swiper image (child) is occasionally blank
  • TextInput jumps when added dynamically
  • image uploading doesn’t work in emulator
  • Loading dependency graph, done.
  • [0.45.1] Cannot find module X
  • [0.45.1] DeviceInfo native module is not installed correctly
  • [0.45.1] Unhandled JS Exception: undefined is not an object
  • [0.47.0] Module JSTimersExecution is not a registered callable module
  • [0.52.1] Error: While resolving module react-native-vector-icons/Octicons
  • [0.52.1] Cannot read property ‘func’ of undefined
  • [0.52.1] Cannot read property ‘appVersion’ of undefined
  • [0.52.1] Invariant Violation: Native component for “BVLinearGradient” does not exist
  • [0.52.1] TypeError: Cannot read property ‘isPickerShow’ of undefined
  • [0.52.1] Cannot read property ‘showImagePicker’ of undefined
  • [0.52.1] TypeError: undefined is not an object (evaluating ‘Contacts.getAll’)
  • [0.52.1] production release crashes on startup (in both Android and iOS devices)
  • [0.59.9] react-native-push-notification: Appears to be a git repo or submodule.
  • [0.59.9] Plugin/Preset files are not allowed to export objects, only functions.
  • [0.59.9] The ‘decorators’ plugin requires a ‘decoratorsBeforeExport’ option, whose value must be a boolean
  • [0.59.9] TypeError: undefined is not an object (evaluating ‘props.getItem’)
  • [0.59.9] withRef is removed

try resetting cache first before googling the error:

$ react-native start --reset-cache

iOS errors

1. React Native — iOS
   (troubleshooting section)

Android errors

1. React Native — Android
   (troubleshooting section)

JS errors

Couldn’t find preset “es2015”

emulator window:

SyntaxError: TransformError: <APP_DIR>/node_modules/shallowequal/index.js:
Couldn't find preset "es2015" relative to directory "<APP_DIR>/node_modules/shallowequal"

solution

it has turned out that shallowequal is the only module in node_modules/ that
configures Babel presets to use in its package.json:

  "babel": {
    "presets": [
      "es2015"
    ]
  },

quick-and-dirty fix for both Android and iOS:

• remove offending section from package.json of shallowequal package
• restart packager — no error
• get that section back
• restart packager — still no error

even if shallowequal package is removed from filesystem and installed again
the error no longer occurs — maybe the ‘right’ version of shallowequal package
is cached somewhere?

NOTE: still the error might occur the next time emulator is run.

[Android] the error might disappear after enabling hot reloading in emulator
(<D-m> → Enable Hot Reloading) — enabling live reload has no effect.

[iOS] enabling hot reloading never helped — use the fix above.

all in all IDK why this error occurs and how to fix it in general.

UPDATE

1. https://github.com/dashed/shallowequal/issues/11
2. https://github.com/dashed/shallowequal/commit/f515936c8a790fbc225add864265b6c82881c9b1

bug was fixed in v1.0.2 by moving Babel settings to .babelrc so that they are
not consumed by RN packager by default.

react-side-effect is the only package that depends on shallowequal package
(according to package-lock.json) => update react-side-effect to update its
dependencies (including shallowequal) to their latest version:

$ npm update react-side-effect

React.Children.only expected to receive a single React element child

device system log:

<Critical>: Unhandled JS Exception: React.Children.only expected to receive a single React element child.

solution

1. https://facebook.github.io/react-native/docs/touchablehighlight.html

TouchableHighlight must have one child (not zero or more than one). If you
wish to have several child components, wrap them in a View.

Maximum call stack size exceeded

device system log:

<Warning>: Warning: Cannot update during an existing state transition
(such as within `render` or another component's constructor).
Render methods should be a pure function of props and state;
constructor side-effects are an anti-pattern, but can be moved to
`componentWillMount`.
<Error>: Maximum call stack size exceeded.
<Critical>: Unhandled JS Exception: Maximum call stack size exceeded.

solution

1. https://stackoverflow.com/questions/37387351

DON’T:

• dispatch Redux actions (this.props.store.dispatch(...)) or
• set component state (this.setState(...))

in render() method or any other method that is called from render() method
(that is when component is being rendered) — this will cause an infinite loop.

for example, if you dispatch action when component is being rendered:

1. reducers update the store according to that action
2. parent component is re-rendered using forceUpdate() (in my case it’s
   subscribed to store updates)
3. component is re-rendered too
4. action is immediately dispatched again (infinite loop)

to avoid infinite loop dispatch actions and set component state only in

• constructor or
• callbacks that are not immediately invoked when component is being rendered

emulator window:

Warning: In next release empty section headers will be rendered. In this
release you can use 'enableEmptySections' flag to render empty section headers.

solution

1. https://github.com/FaridSafi/react-native-gifted-listview/issues/39#issuecomment-217073492

If you use cloneWithRows then you don’t have sections and so there’s no issue
with section headers showing up. The confusing part is that even if you don’t
use sections, it will still throw the warning mentioning sections. In this
case, you can just set enableEmptySections={true} and forget about it.

<ListView
  enableEmptySections={true}
  ...
/>

onEndReached event of ListView keeps on firing

solution

1. https://stackoverflow.com/questions/38531369
2. https://github.com/facebook/react-native/issues/6002
3. https://facebook.github.io/react-native/docs/refreshcontrol.html

don’t nest ListView in ScrollView — this is what causes onEndReached event
to be triggered again and again.

in most cases it means not to use ScrollView at all if you have to use
ListView:

• if you use refreshControl property of ScrollView note that ListView has
  the same property
• if you use some header in ScrollView it’s possible to render the very same
  header in renderHeader callback of ListView

ListView becomes blank

when pushing another page and then going back to page with ListView the latter
becomes blank (nothing is rendered where ListView is supposed to be rendered).
at the same time adjacent components are rendered properly (=> it’s not that
wrapped collection becomes empty).

solution

1. https://github.com/facebook/react-native/issues/8607

<ListView
  removeClippedSubviews={false}
  ...
/>

though I guess it’s more of a hack than real solution.

SyntaxError wallet.png: Unexpected character (1:0)

the error occurs sometimes after adding new icon or updating existing one.

solution

restart packager (react-native start) and reload application in emulator.

Actions must be plain objects

emulator window:

Actions must be plain objects. Use custom middleware for async actions.

the error occurs when trying to dispatch a thunk (Thunk middleware is applied).

solution

I used curly braces instead of parens when defining thunk action creator:

- export const requestCreateAuthentication = (phone_number) => {
+ export const requestCreateAuthentication = (phone_number) => (
   (dispatch, getState, api) => {
     // ...
   }
- }
+ )

TouchableOpacity ignores initial opacity

TouchableOpacity ignores opacity property — it’s set only when application
is hot reloaded in emulator.

solution

1. https://github.com/facebook/react-native/pull/12628
2. https://github.com/facebook/react-native/pull/8909

according to these links the issue has been closed (that is fixed) but it
doesn’t look like this (or maybe it’s another but related issue).

anyway I’ve found a workaround — create nested View and set opacity property
on it instead of TouchableOpacity itself:

<TouchableOpacity>
  <View style={{opacity: 0.5}}>
    <Text>{title}</Text>
  </View>
</TouchableOpacity>

Unknown named module

the error occurs when trying to load image using Image.

device system log:

<Notice>: { [Error: Unknown named module: '~/components/_new/graphics/images/ion-ios-person.png'] ... }

solution

1. https://github.com/facebook/react-native/issues/2481

it turns out you cannot load images dynamically — provide static URI instead
(that is don’t construct it dynamically, say, using variable interpolation):

<Image
  style={{height: 30, width: 35}}
  source={require('~/components/_new/graphics/images/ion-person-stalker.png')}
/>

ScrollView with unbounded height doesn’t grow on scrolling

1. https://stackoverflow.com/a/43525913/3632318

I use ScrollView as a top-level container — when all its content doesn’t fit
on the screen (say, on iPhone 4s), the ScrollView doesn’t grow when trying to
scroll down: hidden content becomes visible but overflows the container.

the solution is to use flexGrow: 1 instead of flex: 1 for container:

<ScrollView
  contentContainerStyle={{flexGrow: 1}}
  scrollEnabled={true}
></ScrollView>

TextInput inside TouchableOpacity intercepts touches

when TouchableOpacity wraps TextInput and the latter is pressed, onPress
callback of TouchableOpacity is not invoked.

solution

1. https://github.com/facebook/react-native/issues/14958#issuecomment-324237317

<TouchableOpacity onPress={this._handlePress}>
  <View pointerEvents='none'>
    <TextInput editable={false} />
  </View>
</TouchableOpacity>

fontWeight={600} is not applied to TextInput

the error occurs if Gill Sans font is used only — setting font weight works with
Text and when default font is used instead.

solution

TODO: still not resolved.

undefined is not an object (evaluating ‘Sentry.options.logLevel’)

device system log:

<Notice>: { [TypeError: undefined is not an object (evaluating 'Sentry.options.logLevel')] ... }

solution

https://github.com/getsentry/react-native-sentry/issues/237#issuecomment-330779566:

Sentry.config(SENTRY_ENDPOINT);
if (!__DEV__) {
  Sentry.install();
}

ScrollView content is partially hidden below when scrolled to the bottom

make sure that all ScrollView parents have flex: 1.

ScrollView inside Modal doesn’t respect keyboardShouldPersistTaps='handled'

1. https://github.com/facebook/react-native/issues/10138

make sure to set keyboardShouldPersistTaps='handled' on ALL parent
ScrollViews outside of Modal:

cares about its (scrollview) parent stack, I assumed it would be like
if rendered on top level

this error seems to be reproduced only when ScrollView is rendered inside
Modal.

Swiper image (child) is occasionally blank

this often happens, say, after removing the child (game in my application) —
adjacent game should become visible but blank area is shown instead.

solution

1. https://github.com/leecade/react-native-swiper/issues/196#issuecomment-249540289
2. https://github.com/leecade/react-native-swiper/issues/609
3. https://facebook.github.io/react-native/docs/scrollview.html#removeclippedsubviews

adding removeClippedSubviews={false} property to Swiper component seems to
solve the problem for the time being (AFAIU when this property is false, all
offscreen children are force rendered — this might be not suitable for long
lists but in my case all lists are short so it shouldn’t be a problem).

UPDATE

still this doesn’t help — the only solution that works thus far is
https://github.com/leecade/react-native-swiper/issues/609#issuecomment-338190488.

UPDATE

nothing of the above works )

consider using react-native-snap-carousel instead of react-native-swiper.

TextInput jumps when added dynamically

solution

set minHeight and initialHeight properties:

<TextInput value='foo' minHeight={20} initialHeight={20} />

image uploading doesn’t work in emulator

response from AWS:

<Error>
  <Code>MalformedPOSTRequest</Code>
  <Message>The body of your POST request is not well-formed multipart/form-data.</Message>
</Error>

emulator window:

[RNDebugger] Detected you've enabled Network Inspect and you're using `uri`
in FormData, it will be a problem if you use it for upload, please see the
documentation (https://goo.gl/yEcRrU) for more information.

solution

1. https://github.com/jhen0409/react-native-debugger/blob/master/docs/network-inspect-of-chrome-devtools.md

disable Network Inspect:

Loading dependency graph, done.

react-native start hangs after Loading dependency graph, done. message.

solution

1. https://github.com/facebook/react-native/issues/16798

I’m not sure but maybe reinstalling Watchman helped to resolve the issue:

$ brew uninstall watchman
$ brew install watchman

[0.45.1] Cannot find module X

$ react-native start
...
> node node_modules/react-native/local-cli/cli.js start

module.js:487
    throw err;
    ^

Error: Cannot find module 'xmldoc'
    at Function.Module._resolveFilename (module.js:485:15)

and similar errors when some module cannot be found.

solution

use yarn instead of npm — somehow it managed to install all required
dependencies:

$ rm package-lock.json
$ rm -rf node-modules
$ yarn install
$ yarn start

[0.45.1] DeviceInfo native module is not installed correctly

emulator window:

DeviceInfo native module is not installed correctly

solution

1. https://github.com/rebeccahughes/react-native-device-info/issues/176

rebuild application.

[0.45.1] Unhandled JS Exception: undefined is not an object

emulator window:

Unhandled JS Exception: undefined is not an object (evaluating 'PropTypes.shape')

solution

1. https://github.com/jsierles/react-native-audio/issues/83

first I tried to upgrade RN again:

$ react-native upgrade
...
You should consider using the new upgrade tool based on Git. It makes upgrades easier by resolving most conflicts automatically.
To use it:
- Go back to the old version of React Native
- Run "npm install -g react-native-git-upgrade"
- Run "react-native-git-upgrade"
See https://facebook.github.io/react-native/docs/upgrading.html

as advised I ran:

$ npm install -g react-native-git-upgrade
$ react-native-git-upgrade

react-native-git-upgrade command downgraded react package to another alpha
version and this is what most likely fixed the issue.

[0.47.0] Module JSTimersExecution is not a registered callable module

1. https://stackoverflow.com/questions/45594935

emulator window:

Module JSTimersExecution is not a registered callable module (calling callTimers)

solution

rebuild application.

[0.52.1] Error: While resolving module react-native-vector-icons/Octicons

$ react-native start
...
error: bundling failed: Error: While resolving module `react-native-vector-icons/Octicons`, the Haste package `react-native-vector-icons` was found. However the module `Octicons` could not be found within the package. Indeed, none of these files exist:

  * `<APP_DIR>/node_modules/react-native/local-cli/core/__fixtures__/files/Octicons(.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json)`
  * `<APP_DIR>/node_modules/react-native/local-cli/core/__fixtures__/files/Octicons/index(.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json)`

solution

1. https://github.com/oblador/react-native-vector-icons/issues/626#issuecomment-357405396
2. https://github.com/oblador/react-native-vector-icons/issues/626#issuecomment-358018994

$ rm ./node_modules/react-native/local-cli/core/__fixtures__/files/package.json
$ react-native start

it looks like this file is recreated after each application build so it makes
sense to add this command to postinstall script in package.json:

  "scripts": {
    "start": "node node_modules/react-native/local-cli/cli.js start",
    "test": "jest",
    "eslint": "eslint",
    "flow": "flow",
+   "postinstall": "rm -f ./node_modules/react-native/local-cli/core/__fixtures__/files/package.json"
  },

[0.52.1] Cannot read property ‘func’ of undefined

error is shown in device system log and emulator window.

the error occurs when evaluating this line:

onPress: React.PropTypes.func.isRequired;

solution

1. https://stackoverflow.com/a/47878585/3632318

PropTypes has been moved to a separate package. Accessing React.PropTypes is
no longer supported and will be removed completely in React 16.

import PropTypes from a separate prop-types package.

[0.52.1] Cannot read property ‘appVersion’ of undefined

error is shown in device system log and emulator window.

the error occurs when evaluating this line:

// node_modules/react-native-device-info/deviceinfo.js

return RNDeviceInfo.appVersion;

solution

1. https://github.com/rebeccahughes/react-native-device-info/issues/52#issuecomment-340212477
2. https://facebook.github.io/react-native/docs/linking-libraries-ios.html#manual-linking

link react-native-device-info library manually and rebuild application.

[0.52.1] Invariant Violation: Native component for “BVLinearGradient” does not exist

error in device system log and emulator window.

solution

1. https://facebook.github.io/react-native/docs/linking-libraries-ios.html#manual-linking

link react-native-linear-gradient library manually and rebuild application.

[0.52.1] TypeError: Cannot read property ‘isPickerShow’ of undefined

error in device system log and emulator window.

solution

1. https://facebook.github.io/react-native/docs/linking-libraries-ios.html#manual-linking

link react-native-picker library manually and rebuild application.

[0.52.1] Cannot read property ‘showImagePicker’ of undefined

error in device system log and emulator window.

solution

1. https://github.com/react-community/react-native-image-picker/issues/712

link react-native-image-picker library manually and rebuild application.

[0.52.1] TypeError: undefined is not an object (evaluating ‘Contacts.getAll’)

error in device system log and emulator window.

solution

link react-native-contacts library manually and rebuild application.

[0.52.1] production release crashes on startup (in both Android and iOS devices)

solution

1. https://github.com/facebook/react-native/issues/16567#issuecomment-340041357
2. https://github.com/facebook/react-native/issues/16542

https://github.com/magus/react-native-facebook-login/issues/279:

View.propTypes has been removed in 0.49

replace View.propTypes.style with ViewPropTypes.style in all components.

see React Native — Android
(debugging section) on how to debug similar problems on Android.

[0.59.9] react-native-push-notification: Appears to be a git repo or submodule.

$ npm install
...
npm ERR! path <APP_DIR>/node_modules/react-native-push-notification
npm ERR! code EISGIT
npm ERR! git <APP_DIR>/node_modules/react-native-push-notification: Appears to be a git repo or submodule.
npm ERR! git     <APP_DIR>/node_modules/react-native-push-notification
npm ERR! git Refusing to remove it. Update manually,
npm ERR! git or move it out of the way first.

solution

1. https://github.com/zo0r/react-native-push-notification/issues/1057

$ rm -rf node_modules/*/.git

[0.59.9] Plugin/Preset files are not allowed to export objects, only functions.

$ react-native start
...
Loading dependency graph, done.
error: bundling failed: Error: Plugin/Preset files are not allowed to export objects, only functions. In <APP_DIR>/node_modules/babel-preset-flow/lib/index.js
    at createDescriptor (<APP_DIR>/node_modules/@babel/core/lib/config/config-descriptors.js:178:11)
    at <APP_DIR>/node_modules/@babel/core/lib/config/config-descriptors.js:109:50
    at Array.map (<anonymous>)
    at createDescriptors (<APP_DIR>/node_modules/@babel/core/lib/config/config-descriptors.js:109:29)
    at createPresetDescriptors (<APP_DIR>/node_modules/@babel/core/lib/config/config-descriptors.js:101:10)
    at presets (<APP_DIR>/node_modules/@babel/core/lib/config/config-descriptors.js:47:19)
    at mergeChainOpts (<APP_DIR>/node_modules/@babel/core/lib/config/config-chain.js:320:26)
    at <APP_DIR>/node_modules/@babel/core/lib/config/config-chain.js:283:7
    at mergeExtendsChain (<APP_DIR>/node_modules/@babel/core/lib/config/config-chain.js:299:21)

solution

1. https://github.com/facebook/flow/issues/7046#issuecomment-443397899

try updating corresponding npm package:

$ npm uninstall babel-preset-flow
$ npm install --save-dev @babel/preset-flow

  // babel.config.js

  module.exports = {
-   presets: ['flow']
+   presets: ['@babel/preset-flow']
  };

[0.59.9] The ‘decorators’ plugin requires a ‘decoratorsBeforeExport’ option, whose value must be a boolean

$ react-native start
...
error: bundling failed: Error: The 'decorators' plugin requires a 'decoratorsBeforeExport' option, whose value must be a boolean. If you are migrating from Babylon/Babel 6 or want to use the old decorators proposal, you should use the 'decorators-legacy' plugin instead of 'decorators'.
    at validatePlugins (<APP_DIR>/node_modules/@babel/parser/lib/index.js:6093:13)
    at getParser (<APP_DIR>/node_modules/@babel/parser/lib/index.js:11286:5)
    at parse (<APP_DIR>/node_modules/@babel/parser/lib/index.js:11256:22)
    at parser (<APP_DIR>/node_modules/@babel/core/lib/transformation/normalize-file.js:170:34)
    at normalizeFile (<APP_DIR>/node_modules/@babel/core/lib/transformation/normalize-file.js:138:11)
    at runSync (<APP_DIR>/node_modules/@babel/core/lib/transformation/index.js:44:43)
    at transformSync (<APP_DIR>/node_modules/@babel/core/lib/transform.js:43:38)
    at Object.transform (<APP_DIR>/node_modules/metro-react-native-babel-transformer/src/index.js:202:20)

solution

1. https://react-redux.js.org/introduction/basic-tutorial#connecting-the-components

https://www.npmjs.com/package/babel-plugin-transform-decorators-legacy#babel—7x

This plugin is specifically for Babel 6.x. If you’re using Babel 7, this
plugin is not for you. Babel 7’s @babel/plugin-proposal-decorators officially
supports the same logic that this plugin has, but integrates better with Babel
7’s other plugins.

but after having tried all possible combinations of decoratorsBeforeExport and
legacy options I still couldn’t make new decorators work. so:

https://github.com/reduxjs/react-redux/issues/1162#issuecomment-453847059

We do not recommend using connect as a decorator, because the spec is
unstable.

=> it’s easier not to use decorators at all (and remove all related packages),
the more especially as it’s a recommended approach.

[0.59.9] TypeError: undefined is not an object (evaluating ‘props.getItem’)

$ adb logcat
...
06-10 00:18:39.077 10262 10367 E ReactNativeJS: TypeError: undefined is not an object (evaluating 'props.getItem')
06-10 00:18:39.077 10262 10367 E ReactNativeJS:
06-10 00:18:39.077 10262 10367 E ReactNativeJS: This error is located at:
06-10 00:18:39.077 10262 10367 E ReactNativeJS:     in FlatList (at YellowBoxList.js:87)
06-10 00:18:39.077 10262 10367 E ReactNativeJS:     in RCTView (at View.js:45)
06-10 00:18:39.077 10262 10367 E ReactNativeJS:     in View (at YellowBoxList.js:79)
06-10 00:18:39.077 10262 10367 E ReactNativeJS:     in YellowBoxList (at YellowBox.js:104)
06-10 00:18:39.077 10262 10367 E ReactNativeJS:     in YellowBox (at AppContainer.js:93)
06-10 00:18:39.077 10262 10367 E ReactNativeJS:     in RCTView (at View.js:45)
06-10 00:18:39.077 10262 10367 E ReactNativeJS:     in View (at AppContainer.js:115)
06-10 00:18:39.077 10262 10367 E ReactNativeJS:     in AppContainer (at renderApplication.js:34)
06-10 00:18:39.090 10262 10367 E ReactNativeJS: TypeError: undefined is not an object (evaluating 'props.getItem')

solution

1. https://github.com/facebook/react-native/issues/21154#issuecomment-439348692

in this case and in case of many other weird JS errors first try resetting
cache:

$ react-native start --reset-cache

[0.59.9] withRef is removed

emulator window:

Unhandled JS Exception: withRef is removed. To access the wrapped instance,
use a ref on the connected component

solution

1. https://react-redux.js.org/api/connect#forwardref-boolean

https://github.com/reduxjs/react-redux/releases/tag/v6.0.0

The withRef option to connect has been replaced with forwardRef. If
{forwardRef : true} has been passed to connect, adding a ref to the connected
wrapper component will actually return the instance of the wrapped component.

https://github.com/reduxjs/react-redux/issues/1291#issuecomment-494188070

Basically, change withRef to forwardRef, and then delete the
.getWrappedInstance() part of componentRef.getWrappedInstance(). componentRef
is your own component now.

say:

  // MyComponent.js

  export default connect(
    mapStateToProps,
    null,
    null,
-   {withRef: true},
+   {forwardRef: true},
  )(MyComponent);

usage:

  <MyComponent ref={ref => this._myComponentRef = ref} />

  // ...
- this._myComponentRef.getWrappedInstance().save();
+ this._myComponentRef.save();

In this article we are going to fix this error i.e. if you are a react native developer then it’s a big possibility that you might come across this error. Let’s understand a solution that works wonders for this error. 

When does this error occur?

This error occurs when we try to run our react-native project on an emulator. For example: with the help of the following command-

npx react-native run-android 

This command starts making the processes work but then it fails when tries to launch the emulator from the android studio. Hence it fails in installing the application.  

Follow the below steps to Fix this error:

Step 1: Launch Android studio and open your project.

Step 2: Go to files and check if Invalidate Caches/Restart… option is active. If it’s not active then click on  Invalidate Caches/Restart… option.

 Step 3: Click on Invalidate and Restart.

• After this, Your project is going to restart again on android studio. 
• Wait until all the Gradle processes are finished. 

Step 4: Clear the cache of your emulator. To clear the cache click on AVD Manager.

Step 5: Click on the down arrow button and click WIPE Data. 

That’s all on the android studio side. For most of the users, the problem may not occur after these steps but if the problem is still not resolved then follow the below steps. 

• Sometimes the metro bundler causes this problem while we try to run the application on the emulator. 
• To resolve that we can start the metro bundler separately. 
• As you would already know that npx react-native run-android does the entire task of running your application. But in this case, we are going to run the metro-bundler separately. 

Step 6: Write this command in your project directory:

npx react-native start --port 8084 --reset-cache

What does this command do? Well, it is going to reset the cache of the metro bundler and launches the metro bundler at the same time.

Now, We will be running the emulator separately. Open a new cmd(command Prompt) window and write the following command in your project directory.

npx react-native run-android 

Note: Close your all previous emulators if they are currently opened. 

Now you can see the build is successful this time.