如何通过此代码固定箭头的上下移动？

Question

我希望箭头的方向随着价格的变化而变化 如果价格上涨，箭头将向更高方向移动 如果价格下跌，箭头将向下 如果不改变，箭头将是3号 我尝试了此代码，但操作无效 这段代码错误吗？

double newPriceEntered = Double.parseDouble(newPrice.getText().toString());
            double old_priceEntered = Double.parseDouble(old_price.getText().toString());
            if (newPriceEntered < old_priceEntered) {
                imageViewD.setImageResource(R.drawable.arrow_up);
            } else if (newPriceEntered > old_priceEntered) {
                imageViewD.setImageResource(R.drawable.arrow_dowen);
            } else {
                imageViewD.setImageResource(R.drawable.arrow_3);
            }

        }

我试图将其添加到MeetAdapter类中，但是没有用

MeetAdapter类：-

public class MeetAdapter extends RecyclerView.Adapter<MeetAdapter.ProductViewHolder> {
    private Context mCtx;
    private List<Meet> meetList;
    public MeetAdapter(Context mCtx, List<Meet> meetList) {
        this.mCtx = mCtx;
        this.meetList = meetList;
    }
    @Override
    public ProductViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        LayoutInflater inflater = LayoutInflater.from(mCtx);
        View view = inflater.inflate(R.layout.meat_list_row, null);
        return new ProductViewHolder(view);
    }
    @Override
    public void onBindViewHolder(ProductViewHolder holder, int position) {
        Meet meet = meetList.get(position);
        Picasso.with(mCtx)
                .load(meet.getUrl_id())
                .into(holder.imageViewM);
        holder.textViewName.setText(meet.getName());
        holder.newPrice.setText(String.valueOf(meet.getPrice()));
        holder.old_price.setText(String.valueOf(meet.getOld_price()));
        holder.textViewDate_id.setText(meet.getDate_id());
    }
    @Override
    public int getItemCount() {
        return meetList.size();
    }
    class ProductViewHolder extends RecyclerView.ViewHolder {
        TextView textViewName, newPrice, old_price, textViewDate_id;
        ImageView imageViewM, imageViewD;
        public ProductViewHolder(View itemView) {
            super(itemView);
            textViewName = itemView.findViewById(R.id.meat_name);
            //old_price = itemView.findViewById(R.id.meat_Direction);
            newPrice = itemView.findViewById(R.id.meat_price);
            textViewDate_id = itemView.findViewById(R.id.meat_date);
            imageViewM = itemView.findViewById(R.id.image_meat);
            imageViewD = itemView.findViewById(R.id.meat_Direction);
            double newPriceEntered = Double.parseDouble(newPrice.getText().toString());
            double old_priceEntered = Double.parseDouble(old_price.getText().toString());
            if (newPriceEntered < old_priceEntered) {
                imageViewD.setImageResource(R.drawable.arrow_up);
            } else if (newPriceEntered > old_priceEntered) {
                imageViewD.setImageResource(R.drawable.arrow_dowen);
            } else {
                imageViewD.setImageResource(R.drawable.arrow_3);
            }

        }
    }
}