Trying to stop propagation using event.stopPropagation() but still bubbling

If you’re using event.stopPropagation() but the event is still bubbling up the DOM tree, there are a few possible reasons and solutions:

1. You’re Using It Too Late (Event Already Propagated)

Problem: If you call stopPropagation() in an asynchronous callback (like setTimeout or fetch), the event may have already bubbled.
Fix: Call it synchronously in the immediate event handler.

✅ Correct:

const handleClick = (event) => {
  event.stopPropagation(); // Works (called immediately)
  console.log("Child clicked");
};

❌ Incorrect (Too Late):

const handleClick = (event) => {
  setTimeout(() => {
    event.stopPropagation(); // ❌ Too late! Event already bubbled.
  }, 0);
};

2. Native Browser Events vs. React SyntheticEvent

Problem: React wraps native events in SyntheticEvent, which pools events for performance (in React 16 and earlier). If you access event.stopPropagation() asynchronously, the event might be nullified.
Fix:
React 17+: No pooling, so event persists.
React 16 or older: Use event.persist() to keep the event.

✅ For React 16 and Below:

const handleClick = (event) => {
  event.persist(); // Keeps the event for async use
  setTimeout(() => {
    event.stopPropagation(); // Now works
  }, 1000);
};

✅ For React 17+:

const handleClick = (event) => {
  // No need for persist(), but still call stopPropagation() synchronously
  event.stopPropagation();
};

3. Event Delegation (Events Higher in the Tree)

Problem: If a parent uses event delegation (e.g., document.addEventListener), stopPropagation() won’t stop it because React events don’t control native DOM listeners.
Fix: Use event.nativeEvent.stopImmediatePropagation() to stop native listeners.

✅ Stopping Native Listeners:

const handleClick = (event) => {
  event.stopPropagation(); // Stops React's event system
  event.nativeEvent.stopImmediatePropagation(); // Stops native listeners
};

4. Multiple Handlers on the Same Element

Problem: If multiple handlers are attached to the same element, stopPropagation() only prevents bubbling to parents—not other handlers on the same element.
Fix: Use stopImmediatePropagation() (for native events).

✅ Stop All Handlers on the Same Element:

const handleClick = (event) => {
  event.nativeEvent.stopImmediatePropagation(); // Stops other listeners
};

5. Capturing Phase vs. Bubbling Phase

Problem: If a parent listens in the capture phase (onClickCapture), stopPropagation() in the bubbling phase won’t stop it.
Fix: Also call stopPropagation() in the capture phase.

✅ Stop During Capture Phase:

// Parent (uses onClickCapture)
<div onClickCapture={(e) => console.log("Parent capture")}>
  <button onClick={(e) => e.stopPropagation()}>Click</button>
</div>

To stop both capture and bubbling:

const handleClick = (event) => {
  event.stopPropagation(); // Stops bubbling
};

const handleClickCapture = (event) => {
  event.stopPropagation(); // Stops capture
};

return (
  <div onClickCapture={handleClickCapture}>
    <button onClick={handleClick}>Click</button>
  </div>
);

Debugging Tips

Check event propagation path:

   console.log(event.nativeEvent.composedPath());

Verify event phase:

event.eventPhase === 1 (CAPTURING_PHASE)
event.eventPhase === 2 (AT_TARGET)
event.eventPhase === 3 (BUBBLING_PHASE)

Summary Table

Issue	Solution
Async `stopPropagation()`	Call it synchronously
React 16 event pooling	Use `event.persist()`
Native event listeners	Use `event.nativeEvent.stopImmediatePropagation()`
Multiple handlers on same element	`stopImmediatePropagation()`
Capture phase listeners	Call `stopPropagation()` in `onClickCapture`

Best Practice

For React events: Use event.stopPropagation() synchronously.
For native events: Use event.nativeEvent.stopImmediatePropagation().
For capture phase: Handle onClickCapture.