CounterLiveData.java

class CounterLiveData extends MutableLiveData<Long> {
    public String toString() {
        return String.format("count=%d", getValue());
    }

    public Long get() {
        return getValue() == null ? 0L : getValue();
    }

    public void set(Long value) {
        if (Looper.getMainLooper().equals(Looper.myLooper())) {
            // UI thread
            setValue(value);
        } else {
            // Non UI thread
            postValue(value);
        }
    }
}