如何更改卡片视图的背景颜色？

Question

Cardview一旦它被点击，我试图改变它的背景颜色。这里列出通知历史记录RecyclerView。Cardview颜色只在那个时候改变。如果我返回并再次打开应用程序意味着它不会被更改。我必须做什么？这是我的适配器类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() {                }            });        }    }}

Answer 1

IsColorChanged您可以在您的内部添加标志，notificationsModel并且每当您更改cardview模型中更新标志的颜色时，

在您的onBindViewHolder中，您可以添加如下检查：

if(IsColorChanged){

    cardView.setCardBackgroundColor(Color.WHITE);

}else{

    cardView.setCardBackgroundColor(Color.BLACK);// ANY OTHER COLOR

}