@Override
    public T set(int index, T object) {
        T val = super.set(index, object);
        if (mListeners != null) {
            mListeners.notifyChanged(this, index, 1);
        }
        return val;
    }
An {@link ObservableList} implementation using ArrayList as an implementation.
android/android_framework/base/src/main/java/github/tornaco/android/thanos/core/util/obs/ObservableArrayList.java