I’m using React Navigation v4, and I need to know if the navigation prop is immutable because I want to wrap my component with React.memo For context here is my (hopefully) pure React component: Answer I’m going to answer my own question based on this tweet by Satyajit Sahoo. It’s not immutable, but it only changes when it needs to
Tag: reactjs
React state not retuning the latest value of state
The value of this.state.topText and this.state.bottomText is always one change behind. E.g if I type 1234 in topText’s input box, the value of this.state.topText would be 123. The react docs say to fix asynchronous updates we should use the form of setState() that accepts a function rather than an object. I have done that and the value of setState is
How to mock/spy useState hook in jest?
I am trying to spy on useState React hook but i always get the test failed This is my React component: counter.test.js: Unfortunately this doesn’t work and i get the test failed with that message: Answer You need to use React.useState instead of the single import useState. I think is about how the code gets transpiled, as you can see
React Material-Ui Sticky Table Header with Dynamic Height
I am using the Material-UI framework for React to display a table. I would like to use a sticky header; however, I do not want to set a height on my table, as I’d like it to scroll with the page. The following snippet does not stick the header unless I set a height on the TableContainer. https://codesandbox.io/s/winter-firefly-5wlx2?file=/src/App.js Answer Get
When I first click the delete button, all the notes are disappeared but, when I refresh the page it works just fine
I tried almost everything. I tested my API to ensure that the problem is not with it. It happens just one time when you visit the page. However, when you refresh it works fine. Before Clicking delete: Click here to see the image After clicking delete button: Click here to see the image Backend Route (home.route.js): React Code: Code for
TypeError: Cannot read property ‘map’ of undefined when I am trying to access API call data
I am trying to make a movie search app with React and have made an API call to The Movie Database API. I have this form and what I am trying to do is get the data of the movie that I am searching for. I am not able to access the data from the API call, and I get
How to change graphs in react from an options form?
I am new in React and I want to change two graphs made in js depending on a form made with bootstrap form. My code in react is the following: I have not been able to change the graph from the options, only the two graphs appear at the same time. Here the image! Answer **I GOT IT!!! I find
Does it matter if the function calls in this loop run concurrently? And if so, how do I make each wait until previous is done?
This code works as expected now, but as my app loads, I am doing API calls to gather data from 8 different tables. I notice that all the calls are happening almost simultaneously and out of order. Order doesn’t actually matter as long as they all happen, as I’m just loading data. I’m just trying to think are there drawbacks
Error: Cannot find module – webpack-dev-server.js
I am building a react app from scratch. Usually, I am running the npm create-react-app and it generates everything for you. I am following this tutorial https://www.youtube.com/watch?v=deyxI-6C2u4&ab_channel=TraversyMedia and it has the GitHub repository in the description. The problem is – when i run “npm start” it should run this command which is written here in the package.json The command works
How I can pass attributes directly to component in vuejs, like reactjs
This is example in react.js: Form.jsx Input.jsx My question is, how can I pass attributes to other components with spread objects? like react.js Answer See this page of the documentation. By binding an object using v-bind (without the spread operator), internally Vue.js will extract out each property and pass them as individual props. In your example above, you would do