如何检查 RecyclerView 中已经存在的文本

Question

public class ChatsFragment extends Fragment {
    public static final String TITLE = "Chats";

FirebaseDatabase database;
DatabaseReference myRef;
List<Listdata> list;
RecyclerView recyclerview;

public static ChatsFragment newInstance() {

    return new ChatsFragment();
}

public View onCreateView(LayoutInflater inflater, ViewGroup group, Bundle b) {
    View view = inflater.inflate(R.layout.fragment_chats, group, false);
    recyclerview = view.findViewById(R.id.rview);
    database = FirebaseDatabase.getInstance();
    myRef = database.getReference("message");
    myRef.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            list = new ArrayList<>();
            for (DataSnapshot dataSnapshot1 : dataSnapshot.getChildren()) {

                UserDetails userdetails = dataSnapshot1.getValue(UserDetails.class);
                Listdata listdata = new Listdata();
                String name = userdetails.getName();
                String message = userdetails.getMessage();
                listdata.setName(name);
                listdata.setMessage(message);
                list.add(listdata);

            }

            RecyclerviewAdapter recycler = new RecyclerviewAdapter(list);
            RecyclerView.LayoutManager layoutmanager = new LinearLayoutManager(getContext());
            recyclerview.setLayoutManager(layoutmanager);
            recyclerview.setItemAnimator(new DefaultItemAnimator());
            recyclerview.setAdapter(recycler);

        }

        @Override
        public void onCancelled(DatabaseError error) {

        }
    });

    return view;
}
}

我有一个回收站 CardView，其中包含 firebase 数据库发送的 names.The 个名称列表。当我两次发送同一个名字时，它显示计数 2.I 想要检查一个已经列出的名字。如果名字已经在RecyclerView我想显示计数2.如何查看名字列表并显示计数

Answer 1

这是你的答案：

  for (DataSnapshot dataSnapshot1 : dataSnapshot.getChildren()) {

            UserDetails userdetails = dataSnapshot1.getValue(UserDetails.class);
            String name = userdetails.getName();
            String message = userdetails.getMessage();
            if (list.contains(new ListData(name,message))) {
               list.set(list.indexOf(new ListData(name,message)),new ListData(name+"check",message);
            } else {
               list.add(new ListData(name,message));
            }

    }

代替“2”，您可以编写代码来增加计数。我将消息视为计数

Answer 2

public class ChatsFragment 扩展片段 {

FirebaseDatabase database;
DatabaseReference myRef;
List<ListData> list;
RecyclerView recyclerview;
HashMap<String,String> hashMap;


public View onCreateView(LayoutInflater inflater, ViewGroup group, Bundle b) {
    View view = inflater.inflate(R.layout.fragment_chats, group, false);
    recyclerview = view.findViewById(R.id.rview);
    database = FirebaseDatabase.getInstance();
    myRef = database.getReference("message");
    hashMap = new HashMap<>();
    myRef.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            list = new ArrayList<>();
                       for (DataSnapshot dataSnapshot1 : dataSnapshot.getChildren()) {

                UserDetails userdetails = dataSnapshot1.getValue(UserDetails.class);
                String name = userdetails.getName();
                String message = userdetails.getMessage();

                if (hashMap.containsKey(name)) {
                    if (!hashMap.get(name).equalsIgnoreCase(message)) {

                        hashMap.remove(name);
                        hashMap.put(name + "-2", message);
                    }
                } else
                    hashMap.put(name, message);

            }

            list = convertHashToObjectList(hashMap);
            RecyclerViewAdapter recycler = new RecyclerViewAdapter(list);
            RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getContext());
            recyclerview.setLayoutManager(layoutManager);
            recyclerview.setItemAnimator(new DefaultItemAnimator());
            recyclerview.setAdapter(recycler);

        }

        @Override
        public void onCancelled(DatabaseError error) {

        }
    });

    return view;
}
private ArrayList<ListData> convertHashToObjectList(HashMap<String, String> chatHashmap){

    ArrayList<ListData> listData = new ArrayList<>();
    for(Map.Entry<String, String> entry: chatHashmap.entrySet()) {
        listData.add(new ListData(entry.getKey(),entry.getValue()));
    }

    return listData;

}

}

这是@ankit 给出的答案。感谢您的解决方案。

如何检查 RecyclerView 中已经存在的文本

How to check the text that is already in RecyclerView or not

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android-recyclerview