I would like to use a discrete Slider component from Material UI to change a picture in a React web app: every time the user changes the value on the slider, a different picture should be displayed in a specified div. How can I do it? I guess that this starts with invoking a handleChange function in onChange …
Tag: reactjs
Intellij WebStorm showing useless usage search on encapsulated React components (using HOC)
It is basically this issue. While using code like I can’t use search usages properly, because it obviously finds the export line. It can be hacked in functional components like this: but gets very ugly when using redux for example: My questions are: Is there a way to overcome this without using such ugl…
React error [Expected an assignment or function call and instead saw an expression]
Today i’m trying to make a Sidebar by following a tutorial after many packages… So tutorial link can be found at youtube here Here is my code who react don’t like: ERROR: Line 24:25: Expected an assignment or function call and instead saw an expression no-unused-expressions Search for the ke…
Do I need to use useEffect to rerender a component?
I had an issue getting a component to update when it´s props changed. I got it to work using useEffect, but am unsure if it is the correct way to solve my problem. This is my code: I was thinking when I updated the props of InputWithDefaultValue it would get rerendered. Is using useEffect to get the component…
How to avoid re-rendering when i pass an object as prop to child component?
I have parent component with multiple child components. Different types of data will be passed to child components after getting data from api. Some of the components will get object as a prop. I am trying to avoid rerenders in that component. Even if the data is same it is rerendering. How can i avoid this r…
My app does not want to re-render, however the list in the context does
Short story: I am making my own GIS (geographic information system) and want to be able to upload JSON files with geographical data. I do not however want to save files in a database, just in a list. Furthermore I’m using Context to send data to the (leaflet) component. When I upload new JSONs to the la…
React router always showing NotFound component
I have routes objects from backend and set it to routes like this and when I am set NotFound component, which route is ‘*’ to default in switch/case or to case “NotFound” which commented now, it all the time show with all components after them. I mean it works all the time, not just in…
react native: there is way to change color of radio button?
there is way to color the whole button both inside and outside ? coz as it now so its color white in outside and the inside is blue but i want it will be white also . i use the react-native-simple-radio-button and u can see the link.. the link Answer when use RadioForm you can set selectedButtonColor prop exa…
ENOENT: no such file or directory when installing react-navigation in react-native project
I’m getting a few errors while I’m installing react-navigation in my react native project with npm install @react-navigation/native The installation goes halfway and stops for a couple minutes and puts this error out. Can someone please help me solve this problem The navigation.navigate(”) i…
Debugging React Context rerenders
I am trying to optimize my React app in order to remove unnecessary renders. Please refer to this Snack for an example: https://snack.expo.io/bUZpyw0kH In this example app, there are two state variables stored in context. One of these values is updated every second, the other never changes. What I am trying t…