Realm-java: RxJava support for finegrained notifications

Created on 2 Mar 2017 · 7Comments · Source: realm/realm-java

We should extend our RxJava support to also include fine-grained notifications. It would be relatively easy to expose as a Pair<RealmResults, ChangeSet>. However naming it might be a bit difficult since asObservable() is already taken.

Some suggestions:

RealmResults<Person> persons = realm.where(Person.class).findAll();
Observable<Pair<RealmResults, OrderedCollectionChangeSet>> obs;

// #1 
obs = persons.asChangeSetObservable();
// #2
obs = persons.asObservable(true); // true = fine-grained, false = standard
// #3
obs = persons.asFinegrainedObservable();
// #4
// .... others?

One thing to consider is also that we will get single object notifications in the near future #4101, which will have similar requirements.

Personally I probably favour 1. with a 2. as a close second, both could be re-used for single object notifications I think. Thoughts @realm/java ?

TODO

[ ] Decide on a method name
[ ] Add new method to RxObservableFactory interface
[ ] Add implementation to RealmObservableFactory class
[ ] Add methods to RealmList/RealmResults
[ ] Unit tests

First-Good-Issue T-Enhancement

Source

cmelchior

👍1

All 7 comments

I'm also wondering how this enhancement affects Rx2 support

Zhuinden on 2 Mar 2017

It doesn't. RxJava1 vs. RxJava2 is a separate discussion ( #3497 ). E.g. this method might just as well be RxRealm.getChangeSetObservable(realmResults) for RxJava2 support.

cmelchior on 2 Mar 2017

I vote asObservable(true) by also keeping asObservable() /without parameters/

Zeyad-37 on 2 Mar 2017

👍1

Thinking about this. Actually 2) is not really possible since the return type will be very different:
```
Observable>
// vs.
Observable, OrderedCollectionChangeSet>

cmelchior on 8 Apr 2017

👍1

I vote 1)