Опорного пункта Android чат RecyclerView автоматическая прокрутка вниз при добавлении нового элемента

Question

Опорного пункта Android чат RecyclerView автоматическая прокрутка вниз при добавлении нового элемента

Я разрабатываю чат для android с помощью firebase.

Я пытался исследовать эту проблему, но не могу найти хорошего решения.

Надеюсь, кто-нибудь сможет мне помочь.

Моя проблема я хочу, чтобы RecyclerView автоматически прокручивался, если добавлен новый элемент.

Вот мой код.

@Nullable

@Override

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){

    View rootView = inflater.inflate(R.layout.chatlayoutchat, container, false);



    Connectivity connectivity=new Connectivity();

    if(connectivity.isConnected(getActivity())) {

        if(getArguments() != null) {

            Firebase.setAndroidContext(this.getActivity());

            String ccustomersid = getArguments().getString("customersid");

            String creferralae = getArguments().getString("referralae");

            String ccustomersname = getArguments().getString("customersname");



            customersid = ccustomersid;

            referralae = creferralae;

            customersname = ccustomersname;



            Firebase.setAndroidContext(this.getActivity());





            editText = (EditText) rootView.findViewById(R.id.editText);



            sendbutton = (Button) rootView.findViewById(R.id.button);

            mRecyclerView = (RecyclerView) rootView.findViewById(R.id.recycler_view);

            RecyclerView.LayoutManager layoutmgr = new LinearLayoutManager(getActivity());

            mRecyclerView.setLayoutManager(layoutmgr);

            mRecyclerView.setItemAnimator(new DefaultItemAnimator());



            final LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity());

            //linearLayoutManager.setReverseLayout(true);

            linearLayoutManager.setStackFromEnd(true);

            mRecyclerView.setLayoutManager(linearLayoutManager);



            from_user = customersid;

            to_user = referralae;

            LoggedInUser = customersname;





            //Log.v("NODE CREATED:", from_user + " " + to_user);





            ref_chatchildnode1 = firebase_chatnode.child(from_user + " " + to_user);



            //ref_chatchildnode2 = firebase_chatnode.child(to_user + " " + from_user);

            sendbutton.setOnClickListener(new View.OnClickListener() {

                @Override

                public void onClick(View view) {

                    newmsg = editText.getText().toString().trim();

                    ChatModel m = new ChatModel();

                    m.setSender(LoggedInUser);

                    m.setMessage(newmsg);

                    ref_chatchildnode1.push().setValue(m);

                    //ref_chatchildnode2.push().setValue(m);

                    editText.setText("");





                }

            });

            ref_chatchildnode1.addChildEventListener(new ChildEventListener() {

                @Override

                public void onChildAdded(DataSnapshot dataSnapshot, String s) {

                    ChatModel chatmsg = dataSnapshot.getValue(ChatModel.class);

                    chatmsgsList.add(chatmsg);

                }



                @Override

                public void onChildChanged(DataSnapshot dataSnapshot, String s) {



                }



                @Override

                public void onChildRemoved(DataSnapshot dataSnapshot) {



                }



                @Override

                public void onChildMoved(DataSnapshot dataSnapshot, String s) {



                }



                @Override

                public void onCancelled(FirebaseError firebaseError) {



                }

            });



        }



    }else{

        nointernet();

    }



    showGlobalContextActionBar();



    return rootView;

}



@Override

public void onStart() {

    super.onStart();

    mFirebaseAdapter1 = new FirebaseRecyclerAdapter<ChatModel, ChatMessageViewHolder>(ChatModel.class,

            R.layout.textview,

            ChatMessageViewHolder.class,

            ref_chatchildnode1) {

        @Override

        protected void populateViewHolder(ChatMessageViewHolder chatMessageViewHolder, ChatModel m, int i) {







            chatMessageViewHolder.sender.setText(m.getSender());

            chatMessageViewHolder.msg.setText(m.getMessage());



        }

    };

    mRecyclerView.setAdapter(mFirebaseAdapter1);



}

660 2

android firebase android-recyclerview firebaseui

2 ответов:

Comments

Ничего не найдено.

Frank van Puffelen · Accepted Answer · 2016-11-25 06:47:16

Посмотрите на Шаг 6 кодовой таблицы Firebase для Android , которая использует AdapterDataObserver для этого:

mFirebaseAdapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
   @Override
   public void onItemRangeInserted(int positionStart, int itemCount) {
       super.onItemRangeInserted(positionStart, itemCount);
       int friendlyMessageCount = mFirebaseAdapter.getItemCount();
       int lastVisiblePosition =
              mLinearLayoutManager.findLastCompletelyVisibleItemPosition();
       // If the recycler view is initially being loaded or the 
       // user is at the bottom of the list, scroll to the bottom 
       // of the list to show the newly added message.
       if (lastVisiblePosition == -1 ||
               (positionStart >= (friendlyMessageCount - 1) &&
                       lastVisiblePosition == (positionStart - 1))) {
           mMessageRecyclerView.scrollToPosition(positionStart);
       }
   }
});

Manikandan K · Accepted Answer · 2016-11-25 06:04:12

Просто попробуйте ниже кода:

         @Override
            public void onStart() {
                super.onStart();
                mFirebaseAdapter1 = new FirebaseRecyclerAdapter<ChatModel, ChatMessageViewHolder>(ChatModel.class,
                        R.layout.textview,
                        ChatMessageViewHolder.class,
                        ref_chatchildnode1) {
                    @Override
                    protected void populateViewHolder(ChatMessageViewHolder chatMessageViewHolder, ChatModel m, int i) {



                        chatMessageViewHolder.sender.setText(m.getSender());
                        chatMessageViewHolder.msg.setText(m.getMessage());

                    }
                };
                mRecyclerView.setAdapter(mFirebaseAdapter1);

        if (mFirebaseAdapter1 != null) { 
                    mRecyclerView.postDelayed(new Runnable() {
                     @Override
                     public void run() { 
                         mRecyclerView.smoothScrollToPosition(mFirebaseAdapter1.getItemCount() - 1);
                     }
                  }, 5); 
              }
            }