Cardview一旦它被點擊，我試圖改變它的背景顏色。這里列出通知歷史記錄RecyclerView。Cardview顏色只在那個時候改變。如果我返回并再次打開應用程序意味著它不會被更改。我必須做什么？這是我的適配器類public class NotificationsAdapter extends RecyclerView.Adapter<NotificationsAdapter.ViewHolder> {    public static final String TAG = "DataViewHolder";    private Context context;    private ArrayList<NotificationsModel> notificationsModelList;    public NotificationsAdapter(Context context, ArrayList<NotificationsModel> notificationsModelList) {        this.context = context;        this.notificationsModelList = notificationsModelList;    }    @Override    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {        View v = LayoutInflater.from(parent.getContext())                .inflate(R.layout.notification_layout, parent, false);        Log.d(TAG, "onCreateViewHolder: ");        return new ViewHolder(v);    }    @Override    public void onBindViewHolder(ViewHolder holder, int position) {        final NotificationsModel notificationsModel = notificationsModelList.get(position);        holder.title_news.setText(notificationsModel.getTitle());        holder.notif_message.setText(notificationsModel.getMessage());    }    @Override    public int getItemCount() {        return notificationsModelList == null ? 0 : notificationsModelList.size();    }    public class ViewHolder extends RecyclerView.ViewHolder {        TextView notif_message, title_news;        //Initializing Views        public ViewHolder(View itemView) {            super(itemView);            title_news = (TextView) itemView.findViewById(R.id.title_news);            notif_message = (TextView) itemView.findViewById(R.id.notif_message);            CardView cardView = (CardView) itemView.findViewById(R.id.cardViewLayoutNotif);            itemView.findViewById(R.id.notif_message);            itemView.setOnClickListener(new View.OnClickListener() {                }            });        }    }}