Android RecyclerView 恢复对象中的状态

问：

该应用程序的功能类似于购物车。用户可以通过单击相应的按钮来添加产品并增加/减少数量。默认情况下，数量值设置为 1。每当用户将新产品添加到recyclerview时，我都会遇到一个问题，以前的产品数量也更改为1。如何避免这种情况？如何恢复对象中的状态（递增/递减值）？

 @Override
public void onBindViewHolder(@NonNull RVOrderBrdAdapter.RVViewHolder holder, int position) {
    //getting the product of the specified position
    OrderBrdDataModel product = filteredList.get(position);

    //binding the data with the viewholder views
    double org_p = product.getBrdprice();
    holder.brd_value.setText(String.valueOf(product.getBrdprice()));
    holder.brd_product.setText(product.getBrdname());
    holder.brd_quantity.setText("1");

    holder.brd_increment.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            number = Integer.parseInt(""+holder.brd_quantity.getText().toString());
            if(holder.brd_quantity.getText().toString().equals("")){
                Toast.makeText(v.getContext(), "Quantity cannot be empty", Toast.LENGTH_SHORT).show();
            }else if(number >=9999){
                Toast.makeText(v.getContext(), "Quantity cannot be greater than 9999", Toast.LENGTH_SHORT).show();

            }else{
                number++;
            }

            holder.brd_quantity.setText(""+number);
            double iw = Double.parseDouble(String.format("%.2f",(org_p*number)));
            holder.brd_value.setText(String.valueOf (iw));
        }
    });

    holder.brd_decrement.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            number = Integer.parseInt(""+holder.brd_quantity.getText().toString());
            if(holder.brd_quantity.getText().toString().equals("")){
                Toast.makeText(v.getContext(), "Quantity cannot be empty", Toast.LENGTH_SHORT).show();
            }else if(number<=0){
                Toast.makeText(v.getContext(), "Quantity cannot be less than 0", Toast.LENGTH_SHORT).show();
                number = 0;
            }else {
                number--;

            }
            holder.brd_quantity.setText(""+number);
            double dw = Double.parseDouble(String.format("%.2f",(org_p*number)));
            holder.brd_value.setText(String.valueOf(dw));
        }
    });