I’m learning React and now I’m trying to do a get request and list with map but when I run this code they come up with this error “Unhandled Rejection (TypeError): this.state.features.map is not a function”. I have already searched this but I do not understand what is going on. Answer …
Tag: javascript
Vue.js dynamically appending HTML when clicking on a button
So basically what I am trying to achieve is allowing the user to be able to add to an existing set of information that will be passed on to Vue from JSON. So the following code is my HTML code which comprises of the div element with the id objectiveArea that vue will render to and a hard coded button
eslint Parsing error: Unexpected token =
Why is eslint throwing this error? The Javascript runs without issue inside of React Native. The code was taken from the react-navigation example at : https://reactnavigation.org/docs/intro/ Javascript: eslint error: .eslintrc.js file: Answer The syntax is not yet standardised, but a stage-2 proposal for incl…
Vue-router error: TypeError: Cannot read property ‘matched’ of undefined
I’m trying to write my first Vuejs app. I’m using vue-cli and simple-webpack boilerplate. When I add vue-router links to my app component I get this error in console Error in render function: “TypeError: Cannot read property ‘matched’ of undefined” Here is my code: App.vue …
Toggle Class based on scroll React JS
I’m using bootstrap 4 nav bar and would like to change the background color after ig 400px down scroll down. I was looking at the react docs and found a onScroll but couldn’t find that much info on it. So far I have… I don’t know if I’m using the right event listener or how to se…
Node Fetch Post Request using Graphql Query
I’m trying to make a POST request with a GraphQL query, but it’s returning the error Must provide query string, even though my request works in PostMan. Here is how I have it running in PostMan: And here is the code I’m running in my application: Any ideas what I’m doing wrong? Is it p…
Chai test array of objects to “contain something like” an object submatch
Ok. I’ve tried to read other questions here but still didn’t find a straightforward answer. How can I assert a partial object match in an array using chai? Something like the following: Just to clarify, my intention is to get as close to the example provided as possible. to chain after the .be.an(…
Rxjs One Observable Feeding into Another
I have a rather clunky looking set of code where the data from one observable is feed into another, like such: I know that there are ways to combine and chain but I need data from source to be feed into source2. The nesting of subscribes looks terrible and I’m pretty certain there is a better way to do …
Do not mutate state directly. Use setState() react/no-direct-mutation-state
I have this code: It is giving me an ESLint warning: Do not mutate state directly. Use setState() react/no-direct-mutation-state. Now what am I supposed to do as I can’t use setState inside constructor directly as it creates error and updating like this gives me error. Answer First of all, we should not…
How to check if an Array is an Array of empty Arrays in Javascript
In my node.js 6.10 app, I am trying to identify in my array looks like this: This nesting can go onto n level, and can have elements in arrays at any level. How can I do this? Thanks P.S. I know I can do it using a n level for loop, but was wondering about a more optimized solution. Answer