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Graph/duplicate-event-listeners-on-render

AntiPattern

Event Handler Accumulation

duplicate-event-listeners-on-render

UI click/interaction logic accumulates duplicate event listeners because registration happens during repeated renders without cleanup, so focus-driven updates trigger multiple identical handlers and stale state changes, producing flicker, unexpected side effects, or controls that appear unresponsive.

Node Details

Public graph metadata

Updated6/28/2026

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30 linked nodes

MATCHESSolution

you can use Zustand getters and optimistic update — multiple or rapid clicks could actually cause the updates to be executed but out of order. Tension: no optimistic update so u see that delay (lag) you said about.

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

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

Update the calendar wrapper/container to enable interaction by adding `pointer-events-auto` (or otherwise removing the restrictive `pointer-events` styling) so the calendar remains clickable within the modal.

MATCHESSolution

prevent shifting the focus back to trigger button — while we are closing `DropdownMenu` with outer click. Tension: tooltip again, incorrectly. Outcome: e.preventDefault().

MATCHESSolution

Handle Radix Popover’s onOpenAutoFocus (or equivalent) and call event.preventDefault() to prevent the Popover from stealing focus from the Input when it opens.

MATCHESSolution

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

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

If you want to filter all unhandled events on Flutter — Flutter. Outcome: you may be interested in this issue https://github.com/getsentry/sentry-dart/issues/456.

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

Move reader.readAsDataURL(file) outside reader.onload and call it after setting the handlers

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

Use a single ref that stores an array of item nodes (via ref callbacks) and update an index-based selection state on keydown. On arrow navigation, focus the corresponding node from the ref array (e.g., refs.current[selectedIndex].focus()).

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

Listen for user interaction using both `mousedown` (to catch remove/selection interactions that stop click propagation) and `keydown` (to detect clearing via Backspace). Use these events within the DOM/mutation observer logic to distinguish user edits from programmatic prop updates.

MATCHESSolution

Listen to the `filterModified` event, store the modified filter model from the UI using `getModelFromUi`, and after each batch update restore the UI state with `setModelIntoUi` (via `getFilterInstance(...).setModelIntoUi(...)`).

MATCHESSolution

Use a ResizeObserver to watch for layout/size changes when the side-panel opens or closes, and re-run the checkPanelState logic on those resize events. Add a debounce to avoid excessive calls.

MATCHESSolution

Define the handler function so the parameter (the event) is declared/inferred (e.g., type-safe handler or convert the project to TypeScript), or add a JSDoc type annotation for the event parameter so IntelliSense can provide completions.

MATCHESSolution

Track image load completion with state (e.g., increment a counter in each Image `onLoad` handler) and only render the button/UI once the counter equals the total number of images.

MATCHESSolution

resize events often occur as many events in quick succession. Tension: the resize behaviour is also a little broken. Outcome: React queues the update.

MATCHESSolution

Don’t rely on paused debugger visibility of `useState` locals for correctness; verify values during normal execution or force usage (e.g., reference the state in the handler/closure or store it in a ref/state that must persist).

MATCHESSolution

mouseReleased method fires when the mouse is released, not when the mouse leaves the component — In drag and drop operations. Outcome: just the normal behaviour.

MATCHESSolution

I can just add the focus listerens to `this` and the parts separately: — `this` and each part using this line:. Outcome: `this.addFocusListener(event -> this.focused = true); Stream.of(part1, part2, part3).forEach(c -> c.addFocusListener(event -> this.focused = true));.

MATCHESSolution

Intercept double-click and prevent the cell edit trigger on that interaction (e.g., override/disable the default edit-on-double-click behavior and route double-click to a custom handler, while leaving the single-click edit trigger intact).

MATCHESSolution

to avoid the flicker — inside the updateGhostLabel method. Tension: renew the JLabel of the panel, and after updating the text, I add it again. Outcome: this forced me to use a null disposition manager.

MATCHESSolution

BuildHash controls when the panel re-renders. — s&box UI uses Razor (.razor files) paired with PanelComponent. Tension: Key patterns:. Outcome: StateHasChanged();.

MATCHESSolution

Keep menu screens and in-game overlays in separate input modes. — Startup/customization menus can force Mouse.Visibility = Visible and keep pointer events enabled. Tension: Startup/customization menus can force Mouse.Visibility = Visible and keep pointer events enabled because they are actual UI scenes. Outcome: Fix pattern:.

MATCHESSolution

Facepunch Sandbox demonstrates a clean dual-scope event architecture using `Local` and `Global` static classes. Tension: Difficulty implementing cancellable events.

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