onKeysSync method
Find multiple records and listen for changes.
First emit happens synchronously.
Returns a single subscriber stream that must be cancelled.
Implementation
Stream<List<K>> onKeysSync(Database database) {
var db = getDatabase(database);
// Create the query but don't add it until first result is set
late QueryKeysListenerController<K, V> ctlr;
ctlr = db.listener.addQueryKeys(
this,
onListen: () async {
await _onListenSync(db, ctlr);
},
);
return ctlr.stream;
}