删除项目后，Recyclerview未刷新

Question

删除项目后，“我的回收器”视图未更新。此recyclerView位于片段内部。我试过各种方法，但都不管用。

片段类中的适配器声明

    notificationsTabAdapter = new NotificationsTabAdapter(getContext(), R.id.notificationsRecyclerView,
                notificationItemsList, cListner);
        layoutManager = new LinearLayoutManager(getContext());
        recyclerView.setLayoutManager(layoutManager);
        recyclerView.setAdapter(notificationsTabAdapter);

回收服务适配器：

public class NotificationsTabAdapter extends RecyclerView.Adapter<NotificationsTabAdapter.NotificationItemHolder> {

Boolean debug = false;
public static final String NOTIFICATION_ADAPTER = "NotificationAdapter";
private ArrayList<NotificationItemm> notificationItems;
private int layoutResID;
private int notificationposition;
private Context myContext;
public onNotificationItemClickListner mListner;


public interface onNotificationItemClickListner {
    void onNotificationItemDelete(int position);
}

public NotificationsTabAdapter(Context context, int resource, ArrayList<NotificationItemm> notificationList,
                               onNotificationItemClickListner listner) {
    myContext = context;
    layoutResID = resource;
    notificationItems = notificationList;
    notificationposition = 0;
    this.mListner = listner;
}

@NonNull
@Override
public NotificationItemHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {

    View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.notifications_tab_item, viewGroup, false);
    NotificationsTabAdapter.NotificationItemHolder evh = new NotificationsTabAdapter.NotificationItemHolder(view, mListner);
    return evh;
}

@Override
public void onBindViewHolder(@NonNull final NotificationItemHolder notificationItemHolder, final int position) {

    final NotificationItemm currentItem = notificationItems.get(position);

    notificationItemHolder.mNotificationTextView.setText(currentItem.getNotification_name());
    notificationItemHolder.mNotificationURL = currentItem.getNotification_link();
    notificationItemHolder.mNotificationDate = currentItem.getNotification_date();
    notificationItemHolder.mNotificationRT = currentItem.getNotification_rT();

    notificationItemHolder.mNotificaionHolderLayout.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

        }
    });
    //to delete the notification
    notificationItemHolder.imageDelete.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            deleteNotification(currentItem);

            mListner.onNotificationItemDelete(position);
        }
    });
}

@Override
public int getItemCount() {
    return notificationItems.size();
}

//Delete from View

public void deleteNotification(NotificationItemm todelete) {
    int notificationPosition = notificationItems.indexOf(todelete);
    notificationItems.remove(notificationPosition);
    notifyItemRemoved(notificationPosition);
    notifyItemChanged(notificationPosition);
    notifyDataSetChanged();
    notifyItemRemoved(notificationPosition);
    notifyItemChanged(notificationPosition);

    if (notificationItems.isEmpty()) {

    }
}

/**
 * VIEW HOLDER =================================================================================
 **/

public class NotificationItemHolder extends RecyclerView.ViewHolder {
    RelativeLayout mNotificaionHolderLayout;
    RelativeLayout notificationParentRelative;
    ImageView imageDelete;
    TextView mNotificationTextView;
    String mNotificationURL;
    String mNotificationDate;
    String mNotificationRT;

    public NotificationItemHolder(@NonNull View itemView, onNotificationItemClickListner listner) {

        super(itemView);
        mNotificationTextView = itemView.findViewById(R.id.NotificationTextView);
        mNotificaionHolderLayout = itemView.findViewById(R.id.notification__item_container);
        imageDelete = itemView.findViewById(R.id.notification_delete_image);
        notificationParentRelative = itemView.findViewById(R.id.rlNotificLayout);
        mNotificationRT = null;
        mNotificationURL = null;
        mNotificationDate = null;
    }
}

}

调试项目时，我可以看到该项实际上正在从ArrayList中删除。但不在循环视图中更新。

删除后，如果滚动回收站视图，则从回收站视图中删除已删除的项。但不是没有滚动。

Answer 1

尝试删除功能

public void deleteNotification(NotificationItemm todelete) {
    notificationItems.remove(todelete);
    notifyDataSetChanged();

}

Answer 2

在NotificationsTabAdapter中，进行以下更改

   NotificationsTabAdapterListener notificationsTabAdapterListener;

   public interface NotificationsTabAdapterListener { // create an interface
        void onItemsDeleted(int position); // create callback function
    }

public NotificationsTabAdapter(Context context, int resource, ArrayList<NotificationItemm> notificationList,
                           NotificationsTabAdapterListener notificationsTabAdapterListener) {
myContext = context;
layoutResID = resource;
notificationItems = notificationList;
notificationposition = 0;
this.notificationsTabAdapterListener = notificationsTabAdapterListener;

}

      notificationItemHolder.imageDelete.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
//perform normal remove operation here

notificationItems.remove(position);
            notificationsTabAdapterListener.onItemsDeleted(position);
        }
    });

并在片段中实现NotificationsTabAdapterListener，在override方法中使用以下代码

        @Override
public void onItemsDeleted(final int position) {
    notificationsTabAdapter.notifyDataSetChanged();
    recyclerView.post(new Runnable() {
        @Override
        public void run() {
            recyclerView.smoothScrollToPosition(position);

        }
    });
}

Answer 3

试试这个。希望对你有用。

notificationItemHolder.imageDelete.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
           notificationItems.remove(position);
           notifyDataSetChanged();
    }