为什么Recycler视图没有调用onCreateViewHolder？

Question

我有一个包含对象列表的回收站视图。这是我的代码：

filter

设置适配器的代码

public class Active_Adapter extends RecyclerView.Adapter<Active_Adapter .ViewHolder> {

    Context con;
    List<ModelQRActiveData> modelQRActiveDatas;
    FragmentManager fragmentManager;
    public QR_Active_Adapter(Context con, List<ModelQRActiveData> modelQRActiveDatas, FragmentManager fragmentManager){
        this.con= con;
        this.modelQRActiveDatas = modelQRActiveDatas;
        this.fragmentManager = fragmentManager;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(con).inflate(R.layout.single_reward, parent, false);
        ViewHolder holder = new ViewHolder(v);
        return holder;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        final ModelQRActiveData modelQRActiveData = modelQRActiveDatas.get(position);

        holder.tv_title_reward.setText(modelQRActiveData.getOffer_name());
        holder.tv_reward_code.setText(modelQRActiveData.getCoupon_code());
        holder.tv_cafe_name_bold.setText(modelQRActiveData.getVenue_name());
        String add=modelQRActiveData.getLocation().getAddress_line_3()+" , "+modelQRActiveData.getLocation().getCity();
        holder.tv_cafe_address.setText(add);
        holder.tv_offer_validity.setText(holder.tv_offer_validity.getText().toString() + " " + modelQRActiveData.getEnd_date());
        holder.tv_offer_know_more.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

               //on click here

            }
        });
        if(position == modelQRActiveDatas.size()-1)
        {
//            Log.e("position", String.valueOf(position));
            holder.bottomView.setVisibility(View.VISIBLE);
        }
    }
    //This is not 0
    @Override
    public int getItemCount() {
        return modelQRActiveDatas.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder
    {
        TextView tv_title_reward, tv_reward_code, tv_cafe_name_bold, tv_cafe_address, tv_offer_validity, tv_offer_know_more;
        View bottomView;
        public ViewHolder(View itemView) {
            super(itemView);
            tv_title_reward = (TextView) itemView.findViewById(R.id.tv_title_reward);
            tv_reward_code = (TextView) itemView.findViewById(R.id.tv_reward_code);
            tv_cafe_name_bold = (TextView) itemView.findViewById(R.id.tv_cafe_name_bold);
            tv_cafe_address = (TextView) itemView.findViewById(R.id.tv_cafe_address);
            tv_offer_validity = (TextView) itemView.findViewById(R.id.tv_offer_validity);
            tv_offer_know_more = (TextView) itemView.findViewById(R.id.tv_offer_know_more);
            tv_title_reward = (TextView) itemView.findViewById(R.id.tv_title_reward);
            bottomView = (View) itemView.findViewById(R.id.bottom_view);
        }
    }

}

但是它在适配器构造函数之后没有调用方法。像onCreateViewHolder一样，并没有调用所有方法。 getITemCount不是0;