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Graph/duplicate-listeners-redundant-state-updates

AntiPattern

Duplicate Event Listener Re-Renders

duplicate-listeners-redundant-state-updates

A recurring event-handling motif where observer/scroll and DOM listeners are attached repeatedly across renders or route changes, causing frequent callbacks that trigger redundant state updates and unnecessary re-renders.

Node Details

Public graph metadata

Updated5/1/2026

Connections

30 linked nodes

MATCHESSolution

For a regular use-case you can do something like this for e.g. the pagination — onPaginationChange: (updater) => {. Tension: updater instanceof Function ? updater(pagination) : updater. Outcome: setSelected(newValue);.

MATCHESSolution

Fix `UserCard` so hooks are always called consistently for each render/instance (and ensure list rendering uses a proper component usage/key pattern). After correcting `UserCard`, the error stopped.

MATCHESSolution

Keep the latest sequence in a mutable ref and have all pointer handlers read from `sequenceRef.current` instead of a captured state value. Update `sequenceRef.current` via a `useEffect` whenever the sequence changes, while registering handlers once (and/or recreating them only based on the ref, not the state).

MATCHESSolution

Treat the selected value as a shared reference (avoid unnecessary cloning/deriving new arrays/objects in selectors). If memory pressure occurs, ensure large datasets are not being copied or accidentally retained (e.g., avoid creating new Float32Array/object instances per render; consider weak caching patterns such as WeakMap only for derived mappings).

MATCHESSolution

Create/move the React.lazy import initialization so it isn’t executed on every render (e.g., place the lazy call in the same component as Suspense) to ensure the import is stable and doesn’t trigger repeated re-renders.

MATCHESSolution

Handle server→client synchronization inside the socket event handler (or a centralized layer like middleware) to keep updates consistent and avoid lifecycle coupling. Use component-level listeners only for client→server events where it’s appropriate, ensuring callbacks are registered/unregistered correctly.

MATCHESSolution

Instead of `useRef`, we can change it to `useState` — for a DOM node that may not exist or change during the component's render. Tension: so that we can track ref changes in the state and trigger re-renders as needed.

MATCHESSolution

Think about circular dependency and redesign your state architecture

MATCHESSolution

Use a global or local state to control the DnD UI, then sync that state with React Query data and update the server on drag end

MATCHESSolution

event.stopPropagation(); handleStatusChange(event); — onChange={(event) => {. Outcome: event.stopPropagation(); handleStatusChange(event);.

MATCHESSolution

make sure that the form component is only rendered after data is ready — Decouple the data fetching component from the form component. Tension: background refetches will not be reflected. Outcome: if your cache already has stale data when `App` mounts, you'll get that data in your state.

MATCHESSolution

I try putting a setName(data.name) inside a useEffect that runs only when "isLoading" changes, and it works — edit/change the "name" retrieved by the query. Tension: I would think there is a better and more clean way to do it. Outcome: use a `useEffect` hook to "synchronize" a React state to an external source.

MATCHESSolution

rendering the rows as a non complex component like a spinner or something — my laggy components were loading in as i scrolled etc. Tension: excessive blanking of the page. Outcome: using useEffect to determine if it is fully rendered, you can resolve most of the major blanking issues.

MATCHESSolution

Remove the catch handlers or re-throw the error after handling it so useMutation can trigger onError

MATCHESSolution

Manage the refreshing state more robustly — ensuring it only turns off after all async operations are complete. Tension: remove the arbitrary timeout. Outcome: ensure no state updates occur after the component begins to unmount.

MATCHESSolution

Create a memoized router context object from the app context and call `router.invalidate()` in a `useEffect` when that memoized object changes, so `beforeLoad`/`loader` rerun with the updated data.

MATCHESSolution

Add a force reload flag — Next.js App Router API route. Tension: ensure functions aren't reused. Outcome: export const dynamic = 'force-dynamic'; export const revalidate = 0;.

MATCHESSolution

No ref to prevent redundant state updates — `setState` inside an observer callback that runs on every scroll event. Tension: React still processes the `setState` call even if the value is the same. Outcome: const lastIdRef = useRef(null);.

MATCHESSolution

The simplest way of achieving this is by using "event delegation" — adding the event to a parent container housing all target elements. Tension: before carrying out the action. Outcome: Make sure that this code is run only once, as soon as the `body` element is in place on your page.

MATCHESSolution

Ensure selectors are properly memoized for the `id` argument (e.g., using selector factory per `id` or `createSelector` with stable input selectors) and limit recomputation by selecting only the needed primitive values/slices; return the original memoized wallet when inputs are unchanged or use referentially stable outputs.

MATCHESSolution

Pass a comparator like shallowEqual (or memoize the derived selector) to prevent rerenders when the selector result hasn’t meaningfully changed.

MATCHESSolution

You are not allowed in Redux, ever, to dispatch from inside a reducer. — Reducer logic has to be a pure synchronous function without side effects. Tension: You might want to do the logic you are currently doing in a thunk or with the listener middleware instead. Outcome: You have to use `createAsyncThunk` for that.

MATCHESSolution

implementing this retry behavior all over the place — axiosInstance.js. Tension: handle the retry logic. Outcome: you could try using a response interceptor to abstract and handle the retry logic.

MATCHESSolution

Keep two listeners or refactor so one wrapper function registers both listeners that call the same shared effect logic; alternatively, create a single predicate/matcher that encompasses both conditions if feasible.

MATCHESSolution

Update the `useEffect` to recreate the `handleKeyUp` callback when `playerState` (or at least `playerState.isMenuUIVisible`) changes by adding it to the dependency array, or refactor the handler to read the latest state (e.g., via a ref) so it doesn’t rely on stale closure values.

MATCHESSolution

the content of the dock gets changed according to the new chat room (even though it's only for a split second) then closes — When I'm in one of the chat rooms, I can change chat rooms by clicking on the other chat rooms. Outcome: place the navigation action in a short timeout so it's placed at the end of Javascript's event loop and allows the dispatched actions to process and React to rerender once.

MATCHESSolution

Add extraReducers/addMatchers for each mutation endpoint (addTour, editTour, removeTour) to update `state.tour` on `matchFulfilled`, or use RTK Query tags and invalidation so queries refetch and state stays in sync.

MATCHESSolution

I suggest a minor refactor to add some local React state to hold this value and a `useEffect` hook — implementing a form with login logout functionality. Tension: This condition will always return true.

MATCHESSolution

Trigger focus after readOnly updates—e.g., set a flag on double-click and call focus in a useEffect (or a callback) once readOnly is false.

MATCHESSolution

`useCallback` needs to be used — to be used as a callback and thus prevent the unnecessary re-renders. Tension: `memo` can't prevent `ExpensiveComponent` from being re-rendered. Outcome: const handleRender = useCallback(() => {...}, []);.

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