chaining-rxjava-7.java

// IDisplayedData implementation (e.g. a Fragment)
private Subscription dataSubscription;

public void refreshData() {
  // Last parameter means delayError = true
  Observable<Timestamped<Data>> dataObservable = domainService.getData(this).observeOn(AndroidSchedulers.mainThread(), true);
  dataSubscription = dataObservable.subscribe(dataOnNext, dataOnError, dataOnComplete);
}

@Override
public long getTimestampMillis() {
  // implement IDisplayedData method to obtain data's last timestamp
}