@TargetApi(Build.VERSION_CODES.HONEYCOMB)
                    @Override
                    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                        super.onScrolled(recyclerView, dx, dy);
                        int max = parallaxView.getHeight();
                        if (dy > 0) {
                            parallaxView.setTranslationY(Math.max(-max, parallaxView.getTranslationY() - dy / 2));
                        } else {
                            parallaxView.setTranslationY(Math.min(0, parallaxView.getTranslationY() - dy / 2));
                        }
                    }
DetailFragmentCallback for when an item has been selected.
app/src/main/java/com/example/android/sunshine/app/ForecastFragment.java