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14 questions linked to/from Cannot read property 'map' of undefined in React
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1 answer
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I try to figure out how I can map over an array of objects which is stored in my state via an api call. My state object: state = { isLoading: false, event: [] }; My render function: {this....
Menelik's user avatar
  • 99
0 votes
1 answer
486 views

I'm using React/Redux, and having an issue parsing through the array of objects of the query I'm receiving. The array I'm trying to parse is contained in its own array that looks like this. {map: "...
ThirdGhostHand's user avatar
  • 397
0 votes
1 answer
541 views

This code below throws an error in Chrome Dev tools but Webpack doesn't report any fault. I am following an online course and the exact same code works for the instructor but not for me. Needless to ...
CallumD's user avatar
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0 answers
96 views

I am making a covid tracker app in react. For this, I have to make a map but it doesn't get rendered. Also, I'm getting an error while trying to loop through the countries. I have attached the code ...
Samantha S's user avatar
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1 answer
78 views

I have tried other answers to questions listed on here and they do not work. What am i doing different? I have an app where I want to list a topic that has a list/array of comments associated with it....
Roro's user avatar
  • 467
0 votes
1 answer
42 views

I'm working on a simple Express/MongoDB/React app. I try to pass the this.state.nearbyShops array retrieved from an API in App.js to the component NearbyShop so that it can be displayed, but the ...
devio's user avatar
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0 votes
0 answers
23 views

I am pretty novice in ReactJS and so I have a question. I have an API that returns a person and the number of children that person has. Now I have another API called persons details and I call it ...
Patrick Ziebell Thøgersen's user avatar
  • 411
9 votes
4 answers
13k views

I'm new with ReactJs/Redux and JSX. I have a dynamical table with dynamic information in it. I have problem with map. I have 2 levels of map: <tbody> { data.map(row => ( <...
Nikita Afanasiev's user avatar
  • 111
2 votes
3 answers
839 views

I try to get data from the backend and display that data in the frontend. This is the code that I wrote to do this task. function ViewPost() { const { id } = useParams(); console.log(id); ...
Walpita's user avatar
  • 83
2 votes
1 answer
926 views

In my react app I am using API calls which should be authenticated by a token. so the first call is for getToken and then storing token in the session, but whenever I start my project it always throws ...
Sharad Mishra's user avatar
  • 187
1 vote
2 answers
860 views

I want to use fields in my map() function, however I get this TypeError: Cannot read property 'fields' of undefined and I don't understand why. Because when I console.log(this.props.schema.fields) I ...
Martin Nordström's user avatar
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0 votes
1 answer
225 views

I have this error and can't really understand what could go wrong when {connect} imported and const mapStateToProps declared: ./src/Movies.js Syntax error: C:/projects/library/src/Movies.js: ...
Fivapr's user avatar
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0 votes
1 answer
121 views

I'm building a search engine with React.js, where I can look for GIPHY gifs, using their API. When I type a word in the search bar, I get this error: Uncaught (in promise) TypeError: props.gifs.map is ...
Timmy's user avatar
  • 165
0 votes
2 answers
27 views

I am trying to implement my first React-Redux app and got TypeError: Cannot read property 'map' of undefined from bundle.js. I guess it is associated with jokes array and its incorrect integration ...
a_zatula's user avatar
  • 458