code: private void inflateRootView() {
          ViewGroup contentView = findViewById(android.R.id.content);
          contentView.removeAllViews();
          LayoutInflater layoutInflater = LayoutInflater.from(getContext());
          rootView =
                  (DraggableView) layoutInflater.inflate(R.layout.bottom_sheet, contentView, false);
          rootView.setCallback(this);
          contentView.addView(rootView, createRootViewLayoutParams());
      }
docs: Initializes the bottom sheet's root view.