如何在GridView的最后一行添加背景色

public class GridAdapter extends BaseAdapter {
    private Context context;
    private List<String> data;

    public GridAdapter(Context context, List<String> data) {
        this.context = context;
        this.data = data;
    }

    @Override
    public int getCount() {
        return data.size();
    }

    @Override
    public Object getItem(int position) {
        return data.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;

        if (convertView == null) {
            convertView = LayoutInflater.from(context).inflate(R.layout.grid_item, parent, false);
            holder = new ViewHolder();
            holder.textView = convertView.findViewById(R.id.text_view);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        // 设置单元格的文本
        holder.textView.setText(data.get(position));

        // 判断是否为最后一行
        if (position >= getCount() - getNumColumns(parent)) {
            // 设置最后一行的背景色
            holder.textView.setBackgroundColor(Color.YELLOW);
        } else {
            // 恢复默认背景色
            holder.textView.setBackgroundColor(Color.TRANSPARENT);
        }

        return convertView;
    }

    private int getNumColumns(ViewGroup parent) {
        // 获取GridView的列数
        GridView gridView = (GridView) parent;
        return gridView.getNumColumns();
    }

    private static class ViewHolder {
        TextView textView;
    }
}