RecyclerView clear list and add new item show old item too

Question

this my adapter

 public class MessageAdapter1 extends RecyclerView.Adapter<MessageAdapter1.ViewHolder> {

private List<MessageList> mMessages;
private int[] mUsernameColors;
private Context context;

public MessageAdapter1(Context context, List<MessageList> messages) {  
mMessages = messages;
this.context = context;
}

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
int layout = -1;

int type = -1;
if(mMessages.get(viewType).getDir().equals("left"))         type = 1;
else if(mMessages.get(viewType).getDir().equals("right"))   type = 0;
else if(mMessages.get(viewType).getDir().equals("typing"))  type = 2;


switch (type) {
case MessageList.TYPE_MESSAGE_RIGHT:
    layout = R.layout.right_message;
    break;
case MessageList.TYPE_MESSAGE_LEFT:
    layout = R.layout.left_message;
    break;
case MessageList.TYPE_ACTION:
    layout = R.layout.message_left;
    break;
}

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

return new ViewHolder(v);
}

@Override
public void onBindViewHolder(ViewHolder viewHolder, int position) {
MessageList message = mMessages.get(position);


viewHolder.setGroupMessage(message);
 }

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



 @Override
 public int getItemViewType(int position) {

 return position;
 }




public class ViewHolder extends RecyclerView.ViewHolder {

private LinearLayout groupMessage;

public ViewHolder(View itemView) {
    super(itemView);

    groupMessage = (LinearLayout)itemView.findViewById(R.id.messages);

}

public void setGroupMessage(MessageList m) {


    if (null == groupMessage) return;

    int i = 0;

    if(m.getMessageStatus() == false){
      m.setMessageStatus(true);
        for (String message : m.getMessageList()) {

            //TextView text = new TextView(activity);
            TextView text = new MyTextView(context);
            LinearLayout.LayoutParams p = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
            p.setMargins(0, 0, 0, 2);

            if (m.getDir().equals("left")) {

                text.setTextColor(Color.BLACK);
                p.gravity = Gravity.LEFT;
                if(m.getMessageList().size() == 1){
                    text.setBackgroundResource(R.drawable.message_left_default);
                }
                else if (i == 0) {
                    text.setBackgroundResource(R.drawable.message_left_first);
                } else if (i + 1 == m.getMessageList().size()) {
                    text.setBackgroundResource(R.drawable.message_left_last);
                } else {
                    text.setBackgroundResource(R.drawable.message_left);
                }


            } else{

                p.gravity = Gravity.RIGHT;
                text.setTextColor(Color.WHITE);

                if(m.getMessageList().size() == 1){
                    text.setBackgroundResource(R.drawable.message_right_default);
                }
                else if (i == 0) {
                    text.setBackgroundResource(R.drawable.message_right_first);
                } else if (i + 1 == m.getMessageList().size()) {
                    text.setBackgroundResource(R.drawable.message_right_last);
                } else {
                    text.setBackgroundResource(R.drawable.message_right);
                }

            }


            text.setLayoutParams(p);
            text.setText(message);
            text.setPadding(8, 8, 8, 8);

            text.setTextSize(18f);



            //text.setTextAppearance(context, android.R.style.TextAppearance_Large);
            groupMessage.addView(text);
            i++;
        }

 }
 }
 }
 }

now initialize the adapter in my activity

public  RecyclerView.Adapter mAdapter;
public  RecyclerView mMessagesView;
public  List<MessageList> Message_List = new ArrayList<MessageList>();

onCreate Activity

    mAdapter = new MessageAdapter1(getApplicationContext(), Message_List);
    mMessagesView = (RecyclerView) findViewById(R.id.messages);
    mMessagesView.setLayoutManager(new LinearLayoutManager(this));
    mMessagesView.setAdapter(mAdapter);

add some data the Message_List

Message_List.add(data);
mAdapter.notifyItemInserted(Message_List.size() - 1);

and the result

now i will clear Message_List the recyclerView must be empty too

clear code

 Message_List.clear();
 mAdapter.notifyDataSetChanged();

result

here the problem when add new item to Messae_List after clear it

add new data now

 Message_List.add(some data new); // message i am new data (first)
 mAdapter.notifyItemInserted(Message_List.size() - 1);

see result

its append my new item in old removed item why the old one was gone i clear the list from where it come back

lets try add new second message

 Message_List.add(some data new); // message i am new data (second)
 mAdapter.notifyItemInserted(Message_List.size() - 1);

result

now add third and forth .... data

result

score 4 · Answer 1 · answered May 26 '20 at 17:48

This code did not solve this issue :

list.remove(position); //remove from list
recycler.removeViewAt(position); //remove view from recyclerview
mAdapter.notifyItemRemoved(position);

But once you add below line on start of onBindViewHolder did the work :

holder.setIsRecyclable(false);

score 2 · Answer 2 · answered Dec 19 '19 at 06:30

2

Please see this link.

To properly remove old items from recyclerview, use following code:

list.remove(position); //remove from list
recycler.removeViewAt(position); //remove view from recyclerview
mAdapter.notifyItemRemoved(position);

answered Dec 19 '19 at 06:30

Vijay E

459
5
12

blkrt · Answer 3 · 2016-07-31T10:19:26.447

0

So instead of Clear The Message_List , Just Create a new instance Of it And

NotifyDataSetChanged That see it have bug or Not....

Or :

mAdapter.remove(position);
mAdapter.notifyDataSetChanged();

edited Jul 31 '16 at 10:19

answered Jul 31 '16 at 10:06

blkrt

197
6

i will try it now .. and i see it in `LOG` old date not found in `Message_List` – medo Jul 31 '16 at 10:08
`Message_List = new ArrayList();` `mAdapter.notifyDataSetChanged();` item still in `RecyclerView` not removed ! – medo Jul 31 '16 at 10:10
try this mAdapter.remove(position); – blkrt Jul 31 '16 at 10:21

score 0 · Answer 4 · edited May 23 '17 at 12:02

0

Can you try like this; create a method in adapter class called refreshMessages. When you want to renew message list call this method.

public void refreshMessages(List<Message_List> messages) {
    this.mMessages = messages;
    notifyItemRangeChanged(0, mMessages.size());
}

To clear all data see this

edited May 23 '17 at 12:02

Community

1
1

answered Jul 31 '16 at 10:24

faranjit

1,461
1
13
19

score -1 · Answer 5 · edited Apr 12 '17 at 20:56

Call removeAll()

public void removeAll() {
    cardItems.clear(); //clear list
    notifyDataSetChanged();
}

After removeAll() you need to init recyclerView again.

private void initRecycleView() {
    recyclerView.setHasFixedSize(true);

    // linear layout manager
    layoutManager = new LinearLayoutManager(this);
    recyclerView.setLayoutManager(layoutManagerTag);

}

Then populate RecyclerView with the data you want.

RecyclerView clear list and add new item show old item too

5 Answers5