I want to update and re-render for loop test condition on hook state update. After I update state hook the state is rerendered but I want to the loop to be rerendered too. I make a form. The length of the form depends on what number I enter on input. Here is what I tried: Answer There is no need
Tag: react-hooks
Uncaught TypeError: Cannot read properties of Undefined (reading ‘getTotalLength’)
I’m trying to animate the SVG with GSAP. But the console.log says “Uncaught TypeError: Cannot read properties of undefined (reading ‘get total length’)”. It reacts project and this is the code I used inside of “useEffect”. Can anyone tell me what’s wrong with my…
React setState of an object with count
I have an array of integers from 0 to 6 as input I need to return an object with the count of each of those numbers but I can’t do the function for the set of values I am expecting this Can you help me? Thank you very much Answer You can use reduce()
Is it valid to use the “return” keyword in a useEffect to stop code execution?
I was debating with a collegue today about using the “return” key in a useEffect to stop code execution. I have learned that using return should only be done in a cleanup. The issue: The way I see this is that we should perhaps have yet another useEffect that only execute if the state is false and…
Unpredictable state change
I am dynamically creating mathlive fields and adding them to the DOM. Though it isn’t a good way but doing it like this because I wasn’t able to add the element as a React component and I needed a workaround quickly Now when I remove an element from array responsible for rendering the elements, it…
React rerender component on database change
Im trying to develop a dynamic todoList. I have two components TodoList, and Todo. TodoList fetches with useSWR the data from Mongo and puts the data in a div depending if they’re completed or not. Todo component has a button to mark if the task its completed or not. When you click the input check it ch…
How do I update dynamic array inside useEffect in Typescript?
I have an array declared as Then set the array with the values as Then I want to update this array from useEffect. I tried below code when displaying subjects array, it is not updating with “Java”. Can anyone help me to solve this? Answer You are not triggering any re-rendering of your component. …
why is MUI CORE basic rating code is giving me setValue as undefined?
i tried using MUI CORE for first time and it’s giving me arror as i wanted to use active first rating and set value is not defined i Answer Ey! The only thing that i can see is that you are trying to use “setValue” in the “onChange” event handler for the “Rating” comp…
Have checked countless times and can’t figure out where my error is: Uncaught TypeError: Cannot read properties of undefined (reading ‘lat’)
I’ve been playing around with the OpenWeatherMap API to learn to code and have run into a series of TypeError issues popping up in my console. My assumption is that my program is attempting to use data from the API before it is finished fetching, but I have set the fetch functions up to wait until recei…
What is a good default value for setting timeout conditionally?
setTimeout returns a number, a timeoutId, which is used by clearTimeout to identify and remove it. However, what value do I use if I want to set the timeout conditionally? Is 0 a safe ID to use? It’s used in a React context where clearing the timeout is generally considered good practice. Or is it perha…