undefined is not an object ( evaluating '_expo.default.Constants')

Question

I would like to debug on my mobile/simulator and point it dynamically to API.

const {manifest} = Expo.Constants; 
const api = manifest.packagerOpts.dev
? manifest.debuggerHost.split(':').shift().concat(':3000')
: 'productionurl.com'


export function getEvents(){
    return fetch('http://${api}/events')
    .then(response => response.json())
    .then(events => events.map(e =>({ ...e, date: new Date(e.date)})));
}

I am getting the following error:

undefined is not an object(evaluating'_expo.default.Constants')

I have imported the same but its reflecting me the same error. — chandra, May 01 '19 at 23:19

Roman · Answer 1 · 2019-10-22T03:38:07.530

15

I work with "sdkVersion": "35.0.0". It seems that Expo changed its API. They extracted and moved some parts into separate packages. Now for this case you need to install a separate dependency:

npm i --save expo-constants

And then to import FileSystem object independently for your component:

import Constants from 'expo-constants';

edited Oct 22 '19 at 03:38

answered Oct 02 '19 at 21:26

Roman

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score 6 · Accepted Answer · edited Feb 28 '20 at 05:31

6

Bring the complete module of the expo with:

import * as Expo from 'expo'

edited Feb 28 '20 at 05:31

fullStackChris

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answered May 07 '19 at 02:16

hong developer

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score 0 · Answer 3 · edited Aug 05 '20 at 17:47

0

When you are working in Snack.expo.io, if you get this error, use the code:

import Constants from 'expo-constants';

This worked for me.

edited Aug 05 '20 at 17:47

β.εηοιτ.βε

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answered Aug 05 '20 at 16:16

Raj

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undefined is not an object ( evaluating '_expo.default.Constants')

3 Answers3