code: private void recyclePreviousSlideView(int position, View view) {
          // Remove view from our hierarchy
          removeView(view);
  
          // Add to recycled views
          int viewType = adapter.getItemViewType(position);
          recycledViews.put(viewType, view);
          view.destroyDrawingCache();
  
          if (view instanceof ImageView) {
              ((ImageView) view).setImageDrawable(null);
          }
  
          Log.d("SlideShowView", "View added to recycling bin: " + view);
  
          // The adapter can recycle some memory with discard slide
          adapter.discardSlide(position);
  
          // The adapter can prepare the next slide
          prepareSlide(getPlaylist().getNextSlide());
      }
docs: Once the previous slide has disappeared, we remove its view from our hierarchy and add it to
  the views that can be re-used.
  
  @param position The position of the slide to recycle
  @param view     The view to recycle