VisibilityTracker.java

class VisibilityRunnable implements Runnable {
        private final List<View> mVisibleViews;
        private final List<View> mInvisibleViews;
        private VisibilityChecker mVisibilityChecker;

        VisibilityRunnable() {
            mVisibleViews = new ArrayList<>();
            mInvisibleViews = new ArrayList<>();
        }

        @Override
        public void run() {
            mIsVisibilityCheckScheduled = false;
            for (final Map.Entry<View, TrackingInfo> entry : mTrackedViews.entrySet()) {
                final View view = entry.getKey();
                final int minPercentageViewed = entry.getValue().mMinVisiblePercent;

                if (mVisibilityChecker.isVisible(view, minPercentageViewed)) {
                    mVisibleViews.add(view);
                } else
                    mInvisibleViews.add(view);
            }

            if (mVisibilityTrackerListener != null) {
                mVisibilityTrackerListener.onVisibilityChanged(mVisibleViews, mInvisibleViews);
            }

            mVisibleViews.clear();
            mInvisibleViews.clear();
        }
    }