无法在聊天室左右显示消息列表，总是在左侧显示所有消息（接收方）

Question

我正在使用 recyclerview 在我的应用程序中显示我的所有消息。但它总是在聊天室的左侧显示消息。

我怎样才能做到这一点？

这是我的代码：

我的适配器总是转到 else 部分并在屏幕左侧列出所有消息（即其他用户消息）

示例图片

适配器：

public class ChatMessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {


 private List<Messages> msgDtoList;
 private final List<Messages> mData;

 public static final int VIEW_TYPE_SENDER = 1;
 public static final int VIEW_TYPE_RECEIVER = 2;

  public ChatMessageAdapter(List<Messages> msgDtoList) {
            this.msgDtoList = msgDtoList;
           mData = msgDtoList;
        }

        public void setData(@Nullable Messages[] data) {
           
            msgDtoList.clear();
            for (Messages model : data) {
                if (model instanceof Messages) {
                    mData.add(model);
                    continue;
                }
}

      @Override
        public int getItemViewType(int position) {
            Messages msgDto = this.msgDtoList.get(position);
               
            if (msgDto.getmSender().getId() == Profile.getInstance().getId()) {
                return VIEW_TYPE_SENDER;
            }

            else {
                return VIEW_TYPE_RECEIVER;
            }

        }

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

        @Override
        public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
            View v;
           

            if(mMessages.getmSender().getId() == Profile.getInstance().getId()) {
                sentViewHolder(holder, position);
              
            } else if  (msgDto.getmSender().getId() != Profile.getInstance().getId()) {
               receivedViewHolder(holder, position);
               
            }
        }

  @SuppressLint("ResourceAsColor")
        private void sentViewHolder(RecyclerView.ViewHolder holder, int position) {
            Messages msgDto = this.msgDtoList.get(position);
            ((SenderMessageHolder)holder).rightMsgTextView.setText(msgDto.getmMSg());
            ((SenderMessageHolder)holder).mDateTimestamp.setText(msgDto.getmTimestamp());
            ((SenderMessageHolder)holder).rightMsgTextView.setTextColor(R.color.yellow);
            ((SenderMessageHolder)holder).rightMsgTextView.setGravity(Gravity.CENTER_VERTICAL | Gravity.RIGHT);
        }

        @SuppressLint("ResourceAsColor")
        private void receivedViewHolder(RecyclerView.ViewHolder holder, int   position) {
            Messages msgDto = this.msgDtoList.get(position);
            ((ReceiverMessageHolder)holder).leftMsgTextView.setText(msgDto.getmMSg());
            ((ReceiverMessageHolder)holder).mDateTimestamp.setText(msgDto.getmTimestamp());
            ((ReceiverMessageHolder)holder).leftMsgTextView.setTextColor(R.color.red);
            ((ReceiverMessageHolder)holder).leftMsgTextView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
        }

        @Override
        public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            Messages msgDto = this.msgDtoList.get(viewType);
           
            if (msgDto.getmSender().getId() == Profile.getInstance().getId() ) {
                View view = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.sender_message_layout, parent, false);
                return new SenderMessageHolder(view);
            } else {
                View view = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.receiver_message_layout, parent, false);
                return new ReceiverMessageHolder(view);
            }
        }

    }
}

在 ChatFragment.java 中

 @Override
    public void onViewCreated(View v, @Nullable Bundle b) {
        super.onViewCreated(v, b);
 mChat = (TextView) v.findViewById(R.id.chat_messages);
        mSendMsgInputBox = (EditText) v.findViewById(R.id.chat_input_msg);
        mSendMsg = (ImageView) v.findViewById(R.id.chat_send_msg);
        mChatMessageRecyclerView = (RecyclerView) v.findViewById(R.id.recycler_view);

        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity());
        linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
        linearLayoutManager.setStackFromEnd(true);
        linearLayoutManager.setSmoothScrollbarEnabled(true);
       
        mChatMessageRecyclerView.setLayoutManager(linearLayoutManager);

        final List<Messages> msgDtoList = new ArrayList<LastMessageContent>();
        int newMsgPosition = msgDtoList.size() - 1;
       
        mChatMessageRecyclerView.scrollToPosition(0);
      

        mChatMessageRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false));
        mChatMessageRecyclerView.setHasFixedSize(true);
        mChatMessageRecyclerView.setAdapter(mAdapter);

        ArrayList<Messages> messagesList = new ArrayList<>();
        for (int i=0;i<10;i++) {
           // messagesList.add(new LastMessageContent( mSendMsgInputBox.getText().toString(), Profile.getInstance().getId() == mChatMessage.getmSender().getId() ? ChatMessageAdapter.VIEW_TYPE_SENDER : ChatMessageAdapter.VIEW_TYPE_RECEIVER));
        }

     


        List<List<Messages>> itemList = new ArrayList<>();
        mSendMsg.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String msgContent = mSendMsgInputBox.getText().toString();

                if(!TextUtils.isEmpty(msgContent))
                {
                    
                    Messages msgDto = mChatMessage.getmessages();
                    msgDtoList.add(msgDto);
                    itemList.add(msgDtoList);
                   
                    mAdapter.notifyDataSetChanged();
                   
                    if (mSendMsgInputBox.toString() != "") {
                       
                        LastMessageContent msgDto1 = new LastMessageContent(mChatMessage.getmLastMessageContent().getmMSg(), mChatMessage.getId());
                        System.out.println("msgDto1msgDto1 ==" + msgDto1);
                        msgDtoList.add(msgDto1);

                    }
                    mAdapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
                        @Override
                        public void onItemRangeInserted(int positionStart, int itemCount) {
                            super.onItemRangeInserted(positionStart, itemCount);
                            int messageCount = mAdapter.getItemCount();
                            int lastVisiblePosition =
                                    linearLayoutManager.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))) {
                                mChatMessageRecyclerView.scrollToPosition(positionStart);
                            }
                        }
                    });
                }
            }

Answer 1

您正在检查您的 viewType 两次。您不应该在 onCreateViewHolder 中再次检查它。

试试这样的：

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
       
        if (viewType == VIEW_TYPE_SENDER) {
            View view = LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.sender_message_layout, parent, false);
            return new SenderMessageHolder(view);
        } else {
            View view = LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.receiver_message_layout, parent, false);
            return new ReceiverMessageHolder(view);
        }
    }