How to add dividers and spaces between items in RecyclerView?

Question

This is an example of how it could have been done previously in the ListView class, using the divider and dividerHeight parame

Answer 1

I forked the DividerItemDecoration from an older gist and simplified it to fit my use case, and I also modified it to draw the dividers the way they are drawn in ListView, including a divider after the last list item. This will also handle vertical ItemAnimator animations:

1) Add this class to your project:

public class DividerItemDecoration extends RecyclerView.ItemDecoration {
    private static final int[] ATTRS = new int[]{android.R.attr.listDivider};
    private Drawable divider;

    public DividerItemDecoration(Context context) {
        try {
            final TypedArray a = context.obtainStyledAttributes(ATTRS);
            divider = a.getDrawable(0);
            a.recycle();
        } catch (Resources.NotFoundException e) {
            // TODO Log or handle as necessary.
        }
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        super.getItemOffsets(outRect, view, parent, state);
        if (divider == null) return;
        if (parent.getChildAdapterPosition(view) < 1) return;

        if (getOrientation(parent) == LinearLayoutManager.VERTICAL)
            outRect.top = divider.getIntrinsicHeight();
        else
            throw new IllegalArgumentException("Only usable with vertical lists");
    }

    @Override
    public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
        if (divider == null) {
            super.onDrawOver(c, parent, state);
            return;
        }

        final int left = parent.getPaddingLeft();
        final int right = parent.getWidth() - parent.getPaddingRight();
        final int childCount = parent.getChildCount();

        for (int i = 0; i < childCount; ++i) {
            final View child = parent.getChildAt(i);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
            final int size = divider.getIntrinsicHeight();
            final int top = (int) (child.getTop() - params.topMargin - size + child.getTranslationY());
            final int bottom = top + size;
            divider.setBounds(left, top, right, bottom);
            divider.draw(c);

            if (i == childCount - 1) {
                final int newTop = (int) (child.getBottom() + params.bottomMargin + child.getTranslationY());
                final int newBottom = newTop + size;
                divider.setBounds(left, newTop, right, newBottom);
                divider.draw(c);
            }
        }
    }

    private int getOrientation(RecyclerView parent) {
        if (!(parent.getLayoutManager() instanceof LinearLayoutManager))
            throw new IllegalStateException("Layout manager must be an instance of LinearLayoutManager");
        return ((LinearLayoutManager) parent.getLayoutManager()).getOrientation();
    }
}

2) Add the decorator to your RecylerView:

recyclerView.addItemDecoration(new DividerItemDecoration(getActivity()));