React Native Firebase 9, cant use off() with reference to unsubscribe from onValue changes-CodePudding

Firebase 9,real time database / react native with expo.

issue: I can not unsubscribe from firebase RTD onChange event listener.

The docs say: "Calling off() on a parent listener does not automatically remove listeners registered on its child nodes; off() must also be called on any child listeners to remove the callback." Firebase docs

error: When I try using .off on the reference I get reference.off() is not a function

const db = getDatabase();
const reference = ref(db, "users/"   props.userId);

const updateScore = (snapshot) => {
  if (snapshot.val() !== null) setHighScore(highscore);
};

useEffect(() => {
  if (props.userId === "") props.navigation.navigate("Auth");
  else onValue(reference, updateScore);
  
  // throws error reference.off() is not a function
  return () => reference.off();
}, [props.userId]);

I've also tried reference.unsubscribe() and reference.removeEventListener(updateScore) with no luck. They both trigger the same error reference.**** is not a function.

Without clearing up this event listener I have a memory leak in my application.

CodePudding user response：

For v9, when you call onValue it returns an unsubscribe function, as shown in the reference docs for onValue. So to unsubscribe:

useEffect(() => {
  if (props.userId === "") props.navigation.navigate("Auth");
  else return onValue(reference, updateScore);
}, [props.userId]);