How is it possible to find out, which tagged work status changed with WorkManager?

Question

I would like to call a function, every time a work with a given tag finished. I do it like this:

LiveData<List<WorkInfo>> liveData = manager.getWorkInfosByTagLiveData(MY_WORK_TAG);
liveData.observe(owner, new Observer<List<WorkInfo>>() {
    @Override
    public void onChanged(List<WorkInfo> workInfos) {
        Log.i("MyWorkManager", "Infos: " + Integer.toString(workInfos.size()));
        // Which WorkInfo changed??
        /*
        if (workInfo.getState() != null && workInfo.getState() == WorkInfo.State.SUCCEEDED) {
            //
        }
        */
    }
});

This code is called, but the workInfos list contains a lot of items, and I have no idea, which WorkInfo was changed in the list. It contains info from works, which were completed a long time ago.