How properly use functionality without leaks? withinAsSingleStreamSubscription

[irizzaflutter]

/// !WARNING! This causes memory leaks because under the hood rxdart StreamController
/// never causes it's subscriptions to be cancelled. So, even you cancel stream
/// subscription created from this method, under the hood listeners are still working.

.within()

when I try to replace it with .withinAsSingleStreamSubscription()

Stream<List> stream = geo.collection(collectionRef: collectionReference)
.withinAsSingleStreamSubscription(center: center, radius: radius, field: field);

its return me that

withinAsSingleStreamSubscription isn't defined for the class 'GeoFireCollectionRef'

[irizzaflutter]

case: when user will scroll map it will show only nearest points with selected radius

e.x when i open map i will get my current location, than i scroll to another city and in that case i need fetch only points from new city with radius N