我无法使用自定义适配器从Firebase片段中获取数据 [英] I can't get data from Firebase in fragment with custom adapter

问题描述

我的代码可以正常工作，但是我无法从Firebase获取数据，我使用了片段的自定义适配器，当我打开片段时，它是空的.我不知道我需要做什么. PS当我在Activity中使用代码时所有工作.在清单中，我拥有所有权限.需要从Firebase获取数据的其他活动，效果很好. 我的代码片段

My code work without error, but i can't get data from Firebase, i use custom adapter for fragment and when i open fragment there are empty. I don't know what i need do. P.S when i use code in Activity all work. In Manifest i have all permissions. Other Activity where need get data from Firebase, working very well. My code Fragment

public class ChatList extends Fragment implements ContactsAdapter.iData, InboxAdapter.inbox_data{
LinearLayoutManager messageLayoutManager,contactsLayoutManager;
ContactsAdapter adapter_contacts;
InboxAdapter adapter_inbox;
ArrayList<User> all_users = new ArrayList<>();
User current;
RecyclerView inbox_rv;
ArrayList<InboxObject> allInboxObjects = new ArrayList<>();

public InboxAdapter.inbox_data inbox_interface;
public static final String CONTACT_TAG = "contact_user";
public static final String CURRENT_USER = "current_user";
GoogleApiClient mGoogleApiClient;
DatabaseReference f_database = FirebaseDatabase.getInstance().getReference();
StorageReference f_storage = FirebaseStorage.getInstance().getReference();

public ChatList() {
    // Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    Context context = container.getContext();
    View layout = LayoutInflater.from(context).inflate(R.layout.fragment_chat_list, container, false);
    inbox_rv = (RecyclerView) layout.findViewById(R.id.inboxsRecyclerView);
    // Inflate the layout for this fragment

    ArrayList<InboxObject> allInboxObjects = new ArrayList<>();
    adapter_inbox = new InboxAdapter(allInboxObjects, getContext(), this);
    inbox_rv.setLayoutManager(messageLayoutManager);
    inbox_rv.setAdapter(adapter_inbox);
    return layout;
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
}
@Override
public void onStart() {
    super.onStart();
    Log.d("demo","onStart");
    f_database.child("users").child(FirebaseAuth.getInstance().getCurrentUser().getUid()).child("inboxobjects").addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            Log.d("demo","onStart:inside inbox data change");
            allInboxObjects.clear();
            for (com.google.firebase.database.DataSnapshot snapshot: dataSnapshot.getChildren()) {


                if(snapshot.getKey().equals(FirebaseAuth.getInstance().getCurrentUser().getUid())){

                }
                else{
                    InboxObject io = snapshot.getValue(InboxObject.class);
                    allInboxObjects.add(io);
                }
            }
            Log.d("demo","Number of inbox is"+ allInboxObjects.size());

            Collections.sort(allInboxObjects, new Comparator<InboxObject>() {
                @Override
                public int compare(InboxObject inboxObject, InboxObject t1) {
                    Date d1 = null;
                    Date d2 = null;
                    try {
                        d1 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").parse(inboxObject.getLastMessage().getCreatedAt());
                        d2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").parse(t1.getLastMessage().getCreatedAt());
                    } catch (ParseException e) {
                        e.printStackTrace();
                    }
                    if(d1.before(d2)){
                        return 1;
                    }
                    else if(d1.after(d2)){
                        return  -1;
                    }
                    else{
                        return 0;
                    }
                }
            });
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
        }
    });
    adapter_inbox = new InboxAdapter(allInboxObjects, getContext(), this);
    inbox_rv.setLayoutManager(messageLayoutManager);
    inbox_rv.setAdapter(adapter_inbox);

}

@Override
public void onItemClick(User u) {
}

@Override
public void onInboxClick(String reciver, String photo, String fn) {
}

}

我的代码自定义适配器

public class InboxAdapter extends RecyclerView.Adapter<InboxAdapter.InboxViewHolder> {
public ArrayList<InboxObject> inbox_list;
public Fragment chatlist;
public Context mContext;
public inbox_data inbox_interface;
public FragmentManager f_manager;
public interface inbox_data{
    void onInboxClick(String reciver, String photo, String fn);
}

DatabaseReference f_database = FirebaseDatabase.getInstance().getReference();
User contact_user;


//  private iData inbox_interface;


public InboxAdapter(ArrayList<InboxObject> inbox_list, Context mContext,inbox_data chatList) {
    this.inbox_list = inbox_list;
    this.f_manager = f_manager;
    this.mContext = mContext;
    this.inbox_interface = (inbox_data) chatList;

}

@Override
public InboxViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View inflatedView = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.layout_inbox, parent, false);
    return new InboxViewHolder(inflatedView);
}

@Override
public void onBindViewHolder(final InboxViewHolder holder, int position) {

    final InboxObject io = inbox_list.get(position);

    holder.lastMsg.setText(io.getLastMessage().getMessage());

    Date date = null;
    try {
        date = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").parse(io.getLastMessage().getCreatedAt());
    } catch (ParseException e) {
        e.printStackTrace();
    }

    holder.time.setText(new SimpleDateFormat("HH:mm-EEE").format(date));

    if(io.getLastMessageRead() == true){
        holder.star.setVisibility(View.INVISIBLE);
    }else{
        holder.star.setVisibility(View.VISIBLE);
    }



    contact_user = io.getReceiver_user();
    holder.contact_username.setText(contact_user.getFirstname()+" "+contact_user.getLastname());

    if(contact_user.getPhotoUrl() == null || contact_user.getPhotoUrl().equals("")){
        holder.contact_avatar
                .setImageDrawable(ContextCompat.getDrawable(mContext,
                        R.drawable.ic_account_circle_black_36dp));
    }
    else{
        Picasso.with(mContext).load(contact_user.getPhotoUrl())
                .into(holder.contact_avatar);
    }

    holder.container.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View view) {
            InboxObject current_object = io;
            contact_user=io.getReceiver_user();
            current_object.setLastMessageRead(true);
            if(inbox_interface != null) {
                String reciver = contact_user.getUid();
                String fn = contact_user.getFirstname();
                String photo = contact_user.getPhotoUrl();
                inbox_interface.onInboxClick(reciver, photo, fn);
            }
            else{
                Log.d("demo","click failed");
            }
        }
    });

    holder.container.setOnLongClickListener(new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(View view) {
            f_database.child("users").child(FirebaseAuth.getInstance().getCurrentUser().getUid()).child("inboxobjects").child(contact_user.getUid()).removeValue();
            f_database.child("users").child(FirebaseAuth.getInstance().getCurrentUser().getUid()).child("inbox").child(contact_user.getUid()).removeValue();
            return true;
        }
    });
}

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

public class InboxViewHolder extends RecyclerView.ViewHolder {
    private CircleImageView contact_avatar;
    private TextView contact_username, time;
    private TextView lastMsg;
    private View container;
    private ImageView star;


    public InboxViewHolder(View itemView) {
        super(itemView);
        contact_username = (TextView) itemView.findViewById(R.id.messengerTextView);
        lastMsg = (TextView) itemView.findViewById(R.id.messageTextView);
        contact_avatar = (CircleImageView) itemView.findViewById(R.id.messengerImageView);
        container = (View) itemView.findViewById(R.id.rowContainer);

        time = (TextView) itemView.findViewById(R.id.timeView);
        star = (ImageView) itemView.findViewById(R.id.starView);

        //container.setOnClickListener(this);
    }

}

}

推荐答案

需要添加此代码片段

adapter_inbox.notifyDataSetChanged();

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