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Android - How to make adapters layout stay in position

I created a simple chat app using firebase but got a little trouble in laying bubble elements for the left and right positions. Left bubble for the other person, right bubble for me.

This is my Adapter :

public class MessageAdapterCustom extends RecyclerView.Adapter<MessageAdapterCustom.MessageViewHolder> {

        private List<Messages> mMessageList;
        private Context context;
        private String mBubblePosition;

        public MessageAdapterCustom(Context context, List<Messages> mMessageList, String mBubblePosition) {
            this.context = context;
            this.mMessageList = mMessageList;
            this.mBubblePosition = mBubblePosition;
        }

        @Override
        public MessageViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

            View v = LayoutInflater.from( parent.getContext() )
                    .inflate( R.layout.message_single_layout_custom, parent, false );

            return new MessageViewHolder( v );
        }

        public class MessageViewHolder extends RecyclerView.ViewHolder {

            public TextView messageText;
            public CircleImageView profileImage;

            public MessageViewHolder(View view) {
                super( view );

                if(mBubblePosition.equals( "kiri" )) {

                    RelativeLayout right = (RelativeLayout) view.findViewById( R.id.sendingMessageLayout );
                    right.setVisibility( View.GONE );

                    messageText = (TextView) view.findViewById( R.id.message_text_layout_kiri );
                    profileImage = (CircleImageView) view.findViewById( R.id.message_profile_layout_kiri );

                } else {

                    LinearLayout left = (LinearLayout) view.findViewById(R.id.recievemessageLayout);
                    left.setVisibility(View.GONE);

                    messageText = (TextView) view.findViewById( R.id.message_text_layout_kanan );
                    profileImage = (CircleImageView) view.findViewById( R.id.message_profile_layout_kanan );

                }

            }
        }

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

            final Messages msg = mMessageList.get( position );
            holder.messageText.setText( msg.getMessage() );

            Picasso.with( context )
                    .load( msg.getProfile_pic() )
                    .networkPolicy( NetworkPolicy.OFFLINE )
                    .into( holder.profileImage );

            /*Picasso.with( context )
                    .load( msg.getProfile_pic() )
                    .networkPolicy( NetworkPolicy.OFFLINE )
                    .placeholder( R.drawable.no_profile )
                    .into( holder.profileImage, new Callback() {
                        @Override
                        public void onSuccess() {

                        }

                        @Override
                        public void onError() {
                            Picasso.with( context )
                                    .load( msg.getProfile_pic() )
                                    .networkPolicy( NetworkPolicy.OFFLINE )
                                    .into( holder.profileImage );
                        }
                    } );*/


        }

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

My ChatActivity :

public class ChatsActivity extends BaseActivity {

        private Toolbar mToolbar;

        private String mChatUser, mChatUserProfileImage;

        private DatabaseReference mRootRef, mMessageDatabase;
        private FirebaseAuth mAuth;

        private TextView mTitleView, mLastSeenView;
        private CircleImageView mProfileImage, mChatProfilePic;

        private String online, image, mCurrentUserID;

        private ImageButton mChatAddBtn, mChatSendBtn;
        private EditText mChatMessageText;

        private RecyclerView mMessagesList;

        private final List<Messages> messagesList = new ArrayList<>();

        private LinearLayoutManager mLinearLayout;

        private MessageAdapter mAdapter;

        private MessageAdapterCustom mAdapterCustom;

        String URL_PROFILE;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate( savedInstanceState );
            setContentView( R.layout.activity_chats );

            mRootRef = FirebaseDatabase.getInstance().getReference();
        /*mRootRef.keepSynced( true );*/

            mAuth = FirebaseAuth.getInstance();
            mCurrentUserID = mAuth.getCurrentUser().getUid();

            mChatUser = getIntent().getStringExtra( "user_id" );
            mChatUserProfileImage = getIntent().getStringExtra( "thumb_image" );

        /*getWindow().setSoftInputMode( WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE );*/

            mToolbar = (Toolbar) findViewById( R.id.toolbar );
            setSupportActionBar( mToolbar );

            mChatAddBtn = (ImageButton) findViewById( R.id.chat_add_btn );
            mChatSendBtn = (ImageButton) findViewById( R.id.chat_send_btn );
            mChatMessageText = (EditText) findViewById( R.id.chat_message );

            mChatMessageText.requestFocus();

            mMessagesList = (RecyclerView) findViewById( R.id.chat_messages_list );

            mLinearLayout = new LinearLayoutManager( this );

            mMessagesList.setHasFixedSize( true );
            mMessagesList.setLayoutManager( mLinearLayout );

            ActionBar actionBar = getSupportActionBar();
            actionBar.setDisplayHomeAsUpEnabled( true );
            actionBar.setDisplayShowCustomEnabled( true );

            final String userName = getIntent().getStringExtra( "user_name" );
            final String thumbProfilePic = getIntent().getStringExtra( "thumb_image" );

            chatUserPic( mChatUser );

            LayoutInflater layoutInflater = (LayoutInflater) this.getSystemService( Context.LAYOUT_INFLATER_SERVICE );
            View action_bar_view = layoutInflater.inflate( R.layout.chat_custom_bar, null );

            actionBar.setCustomView( action_bar_view );

            mTitleView = (TextView) findViewById( R.id.custom_bar_title );
            mLastSeenView = (TextView) findViewById( R.id.custom_bar_seen );
            mProfileImage = (CircleImageView) findViewById( R.id.custom_bar_image );
            mChatProfilePic = (CircleImageView) findViewById( R.id.message_profile_layout );

            mTitleView.setText( userName );

            mRootRef.child( "Users" ).child( mCurrentUserID ).child( "online" ).setValue( "Online" );

            loadMessages();

            mRootRef.child( "Users" ).child( mChatUser ).addValueEventListener( new ValueEventListener() {
                @Override
                public void onDataChange(DataSnapshot dataSnapshot) {
                    mTitleView.setText( userName );

                    online = dataSnapshot.child( "online" ).getValue().toString();
                    image = dataSnapshot.child( "image" ).getValue().toString();

                    if (online.equals( "Online" )) {
                        mLastSeenView.setText( online );
                    } else {

                        GetTimeAgo getTimeAgo = new GetTimeAgo();
                        long lastTime = Long.parseLong( online );
                        String lastSeenTime = getTimeAgo.timeAgo( lastTime, getApplicationContext() );
                        mLastSeenView.setText( lastSeenTime );
                    }
                }

                @Override
                public void onCancelled(DatabaseError databaseError) {

                }
            } );

            mChatMessageText.setOnClickListener( new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    if(mAdapterCustom != null) {
                        mMessagesList.scrollToPosition( mAdapterCustom.getItemCount() - 1 );
                    }
                }
            } );

            mChatMessageText.setOnFocusChangeListener( new View.OnFocusChangeListener() {
                @Override
                public void onFocusChange(View view, boolean hasFocus) {
                    if (hasFocus) {
                        if(mAdapterCustom != null) {
                            mMessagesList.scrollToPosition( mAdapterCustom.getItemCount() - 1 );
                        }
                    } else {
                        if(mAdapterCustom != null) {
                            mMessagesList.scrollToPosition( mAdapterCustom.getItemCount() - 1 );
                        }
                    }
                }
            } );


            mRootRef.child( "Chat" ).child( mCurrentUserID ).addValueEventListener( new ValueEventListener() {
                @Override
                public void onDataChange(DataSnapshot dataSnapshot) {
                    if (!dataSnapshot.hasChild( mChatUser )) {

                        Map chatAddMap = new HashMap();
                        chatAddMap.put( "seen", false );
                        chatAddMap.put( "timestamp", ServerValue.TIMESTAMP );

                        Map chatUserMap = new HashMap();
                        chatUserMap.put( "Chat" + "/" + mCurrentUserID + "/" + mChatUser, chatAddMap );
                        chatUserMap.put( "Chat" + "/" + mChatUser + "/" + mCurrentUserID, chatAddMap );

                        mRootRef.updateChildren( chatUserMap, new DatabaseReference.CompletionListener() {
                            @Override
                            public void onComplete(DatabaseError databaseError, DatabaseReference databaseReference) {
                                if (databaseError != null) {
                                    Log.e( "CHAT_LOG", databaseError.getMessage().toString() );
                                } else {
                                    mMessagesList.scrollToPosition( mAdapterCustom.getItemCount() - 1 );
                                }
                            }
                        } );

                    }
                }

                @Override
                public void onCancelled(DatabaseError databaseError) {

                }
            } );

            mChatSendBtn.setOnClickListener( new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    final String message = mChatMessageText.getText().toString();
                    if (TextUtils.isEmpty( message )) {
                        onError( "Message cannot be empty!" );
                    } else {
                        DatabaseReference reference = FirebaseDatabase.getInstance().getReference();
                        Query query = reference.child( "Users" ).child( mCurrentUserID );
                        query.addListenerForSingleValueEvent( new ValueEventListener() {
                            @Override
                            public void onDataChange(DataSnapshot dataSnapshot) {

                                if (dataSnapshot.exists()) {
                                    final String URL_PROFILE = dataSnapshot.child( "thumb_image" ).getValue().toString();
                                    sendMessage( message, URL_PROFILE );
                                }
                            }

                            @Override
                            public void onCancelled(DatabaseError databaseError) {

                            }
                        } );

                    }
                }
            } );

        }

        private void chatUserPic(String id) {
            DatabaseReference reference = FirebaseDatabase.getInstance().getReference();
            Query query = reference.child( "Users" ).child( id );
            query.addListenerForSingleValueEvent( new ValueEventListener() {
                @Override
                public void onDataChange(DataSnapshot dataSnapshot) {

                    if (dataSnapshot.exists()) {
                        final String URL_PROFILE = dataSnapshot.child( "thumb_image" ).getValue().toString();
                        Picasso.with( getApplication() )
                                .load( URL_PROFILE )
                                .networkPolicy( NetworkPolicy.OFFLINE )
                                .placeholder( R.drawable.no_profile )
                                .into( mProfileImage, new Callback() {
                                    @Override
                                    public void onSuccess() {

                                    }

                                    @Override
                                    public void onError() {
                                        Picasso.with( getApplication() )
                                                .load( URL_PROFILE )
                                                .placeholder( R.drawable.no_profile )
                                                .into( mProfileImage );
                                    }
                                } );
                    } else {
                        String URL_PROFILE = "no_profile";
                        Log.i( "PAUL", URL_PROFILE );
                    }
                }

                @Override
                public void onCancelled(DatabaseError databaseError) {

                }
            } );
        }


        private void loadMessages() {

            mRootRef.child( "Messages" ).child( mCurrentUserID ).child( mChatUser ).addChildEventListener( new ChildEventListener() {
                @Override
                public void onChildAdded(DataSnapshot dataSnapshot, String s) {

                    Messages message = dataSnapshot.getValue( Messages.class );

                    String currentUserID = message.current_user_id.toString();

                /*mAdapter = new MessageAdapter( getApplicationContext(), messagesList );*/

                    if (currentUserID.equals( mCurrentUserID )) {
                        mAdapterCustom = new MessageAdapterCustom( getApplicationContext(), messagesList, "kanan" );
                        mMessagesList.setAdapter( mAdapterCustom );
                        messagesList.add( message );
                        mAdapterCustom.notifyDataSetChanged();
                        Log.i( "CHAT_ACTIVITY", "RIGHT" );
                    } else {
                        mAdapterCustom = new MessageAdapterCustom( getApplicationContext(), messagesList, "kiri" );
                        mMessagesList.setAdapter( mAdapterCustom );
                        messagesList.add( message );
                        mAdapterCustom.notifyDataSetChanged();
                        Log.i( "CHAT_ACTIVITY", "LEFT" );
                    }

                /*mMessagesList.scrollToPosition( mAdapterCustom.getItemCount() - 1 );*/
                }

                @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(DatabaseError databaseError) {

                }
            } );
        }

        private void sendMessage(String message, String profile_pic) {

            String current_user_ref = "Messages" + "/" + mCurrentUserID + "/" + mChatUser;
            String chat_user_ref = "Messages" + "/" + mChatUser + "/" + mCurrentUserID;

            DatabaseReference user_message_push = mRootRef.child( "Messages" )
                    .child( mCurrentUserID ).child( mChatUser ).push();


            String push_id = user_message_push.getKey();

            Map messageMap = new HashMap();
            messageMap.put( "message", message );
            messageMap.put( "seen", false );
            messageMap.put( "type", "text" );
            messageMap.put( "time", ServerValue.TIMESTAMP );
            messageMap.put( "profile_pic", profile_pic );
            messageMap.put( "current_user_id", mCurrentUserID );


            Map messageUserMap = new HashMap();
            messageUserMap.put( current_user_ref + "/" + push_id, messageMap );
            messageUserMap.put( chat_user_ref + "/" + push_id, messageMap );

            mRootRef.updateChildren( messageUserMap, new DatabaseReference.CompletionListener() {
                @Override
                public void onComplete(DatabaseError databaseError, DatabaseReference databaseReference) {
                    if (databaseError != null) {
                        mChatMessageText.setText( "" );
                        Log.e( "SEND_MESSAGE_CHAT", databaseError.getMessage().toString() );
                    } else {
                        mChatMessageText.setText( "" );
                        mMessagesList.scrollToPosition( mAdapterCustom.getItemCount() - 1 );
                    }
                }
            } );

        }

        @Override
        protected void onStart() {
            super.onStart();
            mRootRef.child( "Users" ).child( mCurrentUserID ).child( "online" ).setValue( "Online" );
            mMessagesList.getLayoutManager().scrollToPosition( mLinearLayout.findLastVisibleItemPosition() + 1000 );
        }

}  

You see the line :

if (currentUserID.equals( mCurrentUserID )) {
   mAdapterCustom = new MessageAdapterCustom( getApplicationContext(), messagesList, "kanan" );
   mMessagesList.setAdapter( mAdapterCustom );
   messagesList.add( message );
   mAdapterCustom.notifyDataSetChanged();
   Log.i( "CHAT_ACTIVITY", "RIGHT" );
} else {
   mAdapterCustom = new MessageAdapterCustom( getApplicationContext(), messagesList, "kiri" );
   mMessagesList.setAdapter( mAdapterCustom );
   messagesList.add( message );
   mAdapterCustom.notifyDataSetChanged();
   Log.i( "CHAT_ACTIVITY", "LEFT" );
}

When I try to use two devices, first if I myself try to send a message, Log shows RIGHT which means the position of the balloon on the right . 在此输入图像描述

But when I reply with different devices (the other person) then the adapter will move the two bubbles to the left . It seems because it follows the last adapter command. 在此输入图像描述

My Log 在此输入图像描述

How do I keep my adapter in position every time a message arrives , instead of changing all the structure of my view elements as shown.

-- Update -- My Layout :

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/stackoverflow"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="5dp">

    <LinearLayout
        android:id="@+id/recievemessageLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <de.hdodenhof.circleimageview.CircleImageView
            android:id="@+id/message_profile_layout_kiri"
            android:layout_width="55dp"
            android:layout_height="55dp"
            android:src="@drawable/no_profile" />

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <TextView
                android:id="@+id/message_text_layout_kiri"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginStart="10dp"
                android:layout_marginTop="5dp"
                android:background="@drawable/message_text_background"
                android:paddingBottom="5dp"
                android:paddingLeft="10dp"
                android:paddingRight="10dp"
                android:paddingTop="5dp"
                android:text="@string/message_here"
                android:textColor="@android:color/white" />

            <ImageView
                android:id="@+id/message_buble_kiri"
                android:layout_width="20dp"
                android:layout_height="20dp"
                android:layout_marginStart="10dp"
                android:layout_marginTop="-10dp"
                android:src="@drawable/buble_left" />

        </LinearLayout>

    </LinearLayout>

    <RelativeLayout
        android:id="@+id/sendingMessageLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/recievemessageLayout"
        android:layout_marginTop="5dp"
        android:orientation="horizontal">

        <de.hdodenhof.circleimageview.CircleImageView
            android:id="@+id/message_profile_layout_kanan"
            android:layout_width="55dp"
            android:layout_height="55dp"
            android:layout_alignParentEnd="true"
            android:src="@drawable/no_profile" />

        <TextView
            android:id="@+id/message_text_layout_kanan"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:layout_marginEnd="10dp"
            android:layout_marginTop="5dp"
            android:layout_toStartOf="@+id/message_profile_layout_kanan"
            android:background="@drawable/message_text_background"
            android:paddingBottom="5dp"
            android:paddingLeft="10dp"
            android:paddingRight="10dp"
            android:paddingTop="5dp"
            android:text="@string/message_here"
            android:textColor="@android:color/white" />

        <ImageView
            android:id="@+id/message_buble_kanan"
            android:layout_width="20dp"
            android:layout_height="20dp"
            android:layout_alignEnd="@+id/message_text_layout_kanan"
            android:layout_below="@+id/message_text_layout_kanan"
            android:layout_marginTop="-10dp"
            android:src="@drawable/buble_right" />


    </RelativeLayout>

</RelativeLayout>

You are currently creating two different adapters with all messages aligned the same direction. Instead, you should create one adapter decides how to align each message one at a time.

RecyclerView with multiple View Type?

public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
        class ViewHolder0 extends RecyclerView.ViewHolder {
            ...
            public ViewHolder0(View itemView){
            ...
            }
        }

        class ViewHolder2 extends RecyclerView.ViewHolder {
            ...
            public ViewHolder2(View itemView){
            ...
        }

        @Override
        public int getItemViewType(int position) {
            // Just as an example, return 0 or 2 depending on position
            // Note that unlike in ListView adapters, types don't have to be contiguous
            return position % 2 * 2;
        }

        @Override
        public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
             switch (viewType) {
                 case 0: return new ViewHolder0(...);
                 case 2: return new ViewHolder2(...);
                 ...
             }
        }

        @Override
        public void onBindViewHolder(final RecyclerView.ViewHolder holder, final int position) {
            switch (holder.getItemViewType()) {
                case 0:
                    ViewHolder0 viewHolder0 = (ViewHolder0)holder;
                    ...
                    break;

                case 2:
                    ViewHolder2 viewHolder2 = (ViewHolder2)holder;
                    ...
                    break;
            }
        }
    }

Items in your list of messages will primarily be of two types: sent and received. Could you make your data model such that they define their types and in onCreateViewHolder() you have a different viewholder for each type. In onBindViewHolder() you need to bind your views again on the basis of the type of item.

I have modified Naveen's example a bit to get :

interface MsgType {
        int TYPE_SENT = 1;
        int TYPE_RECEIVED = 2;
    }

    class Msg implements MsgType
    {
        String text ;
        int type;

        public Msg(String text, int type) {
            // set 
        }

        public String getText() {
            return text;
        }

        public int getType() {
            return type;
        }
    }

    public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
        List<Msg> msgs;

        class SentMsgVH extends RecyclerView.ViewHolder {
            ...
            public SentMsgVH(View itemView){
            ...
            }
        }

        class ReceivedMsgVh extends RecyclerView.ViewHolder {
            ...
            public ReceivedMsgVh(View itemView){
            ...
        }

        @Override
        public int getItemViewType(int position) {
            return msgs.get(position).getType();
        }

        @Override
        public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View v;
             switch (viewType) {
                 case TYPE_SENT: 
                    v = ... ; // inflate view
                    return new SentMsgVH(v);
                 case TYPE_RECEIVED:
                    v = ...; // inflate view
                    return new ReceivedMsgVh(v);
             }
        }

        @Override
        public void onBindViewHolder(final RecyclerView.ViewHolder holder, final int position) {
            switch (getItemViewType(position)) {
                case TYPE_SENT:
                    ViewHolder0 viewHolder0 = (SentMsgVH)holder;
                    ...
                    break;

                case TYPE_RECEIVED:
                    ViewHolder2 viewHolder2 = (ReceivedMsgVh)holder;
                    ...
                    break;
            }
        }
    }

In your respective viewholders you should inflate the proper layout as per your needs.

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