ItemDecoration -如何创建垂直分隔符？

public class VerticalDividerItemDecoration extends RecyclerView.ItemDecoration {
    private Drawable divider;

    public VerticalDividerItemDecoration(Drawable divider) {
        this.divider = divider;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        outRect.set(0, 0, 0, divider.getIntrinsicHeight());
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
        int left = parent.getPaddingLeft();
        int right = parent.getWidth() - parent.getPaddingRight();

        int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            View child = parent.getChildAt(i);

            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();

            int top = child.getBottom() + params.bottomMargin;
            int bottom = top + divider.getIntrinsicHeight();

            divider.setBounds(left, top, right, bottom);
            divider.draw(c);
        }
    }
}

RecyclerView recyclerView = findViewById(R.id.recycler_view);
Drawable divider = ContextCompat.getDrawable(this, R.drawable.divider); // 自定义分隔符样式，可替换为自己的 drawable
RecyclerView.ItemDecoration itemDecoration = new VerticalDividerItemDecoration(divider);
recyclerView.addItemDecoration(itemDecoration);