Repeating items in ListView?

Question

Everything was working fine but now I am not getting what is happening,I have 10 items to display in the listView,its working fine till the 6th item and after that it repeats again from the 1st item again??

    public class GroupDetailsAdapter extends BaseAdapter {
        List<GetSetGroupDetails> group_details = new ArrayList<GetSetGroupDetails>();
        Context context;
        Typeface face;

        public GroupDetailsAdapter(List<GetSetGroupDetails> group_details,
                Context context) {
            super();
            this.group_details.clear();
            this.group_details = group_details;
            this.context = context;
            face = Typeface.createFromAsset(context.getAssets(),
                    "HelveticaNeueLTStd-Th.otf");
        }

        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            int count = group_details.size();
            return count;
        }

        @Override
        public Object getItem(int arg0) {
            // TODO Auto-generated method stub
            return null;
        }

        @Override
        public long getItemId(int position) {
            // TODO Auto-generated method stub
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            // TODO Auto-generated method stub

            View v = convertView;
            ViewHolder holder;
            if (v == null) {
                try {

                    LayoutInflater vi = (LayoutInflater) context
                            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                    v = vi.inflate(R.layout.group_item, null);
                    holder = new ViewHolder();

                    holder.tv_group_name = (TextView) v
                            .findViewById(R.id.tv_group_name);
                    String group_name = group_details.get(position).getGroup_name();
                    holder.tv_group_name.setText(group_name);
                    holder.tv_group_name.setTypeface(face);

                    holder.tv_group_reg_id = (TextView) v
                            .findViewById(R.id.tv_group_reg_id);
                    String groupRegId = group_details.get(position)
                            .getGroup_reg_id();
                    holder.tv_group_reg_id.setText(groupRegId);
                    holder.tv_group_reg_id.setTypeface(face);   

                    holder.tv_subscriber_count = (TextView) v
                            .findViewById(R.id.tv_subscriber_count);
                    holder.tv_subscriber_count.setText(group_details.get(position)
                            .getSubscriber_count());

                    v.setTag(holder);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            } else
                holder = (ViewHolder) v.getTag();
            return v;

        }

        class ViewHolder {
            TextView tv_group_name;
            TextView tv_group_reg_id;
            TextView tv_subscriber_count;

        }

    }

_I might be wrong_, you are essentially repeating the non null views. Try moving the `setText()` lines to after if-else block. — hypd09, Jun 02 '14 at 12:57
just call .clear(); method on list before you fill the adpter — Android, Jun 02 '14 at 13:03
yeah you only assign values when views are created, so the recycled views just keep the old values — rupps, Jun 02 '14 at 14:41

score 21 · Accepted Answer · answered Jun 02 '14 at 12:58

You are facing that data repeat issue, just because you aren't following the exact standards of implementing View-Holder pattern.

Wrong:

Here you are doing findViewById() and setting data if view is null, so it will be running fine for first set of items, afterword it will show you the same data for the next sets of items.

public View getView(int position, View convertView, ViewGroup parent) {
            // TODO Auto-generated method stub

            View v = convertView;
            ViewHolder holder;
            if (v == null) {
                try {

                    LayoutInflater vi = (LayoutInflater) context
                            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                    v = vi.inflate(R.layout.group_item, null);
                    holder = new ViewHolder();

                    holder.tv_group_name = (TextView) v
                            .findViewById(R.id.tv_group_name);
                    String group_name = group_details.get(position).getGroup_name();
                    holder.tv_group_name.setText(group_name);
                    holder.tv_group_name.setTypeface(face);

                    holder.tv_group_reg_id = (TextView) v
                            .findViewById(R.id.tv_group_reg_id);
                    String groupRegId = group_details.get(position)
                            .getGroup_reg_id();
                    holder.tv_group_reg_id.setText(groupRegId);
                    holder.tv_group_reg_id.setTypeface(face);   

                    holder.tv_subscriber_count = (TextView) v
                            .findViewById(R.id.tv_subscriber_count);
                    holder.tv_subscriber_count.setText(group_details.get(position)
                            .getSubscriber_count());

                    v.setTag(holder);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            } else
                holder = (ViewHolder) v.getTag();
            return v;

        }

Correct:

Correct way to implement View Holder pattern is to find views if current view is null (that would happen for the first time) and set data only after doing it. So eventually findViewById() process will be done for the first time and next time onwards it will get views by using attached tags.

public View getView(int position, View convertView, ViewGroup parent) {
            // TODO Auto-generated method stub

            View v = convertView;
            ViewHolder holder;
            if (v == null) {
                    LayoutInflater vi = (LayoutInflater) context
                            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                    v = vi.inflate(R.layout.group_item, null);

                    holder = new ViewHolder();

                    holder.tv_group_name = (TextView) v
                            .findViewById(R.id.tv_group_name);
                    holder.tv_group_reg_id = (TextView) v
                            .findViewById(R.id.tv_group_reg_id);
                    holder.tv_subscriber_count = (TextView) v
                            .findViewById(R.id.tv_subscriber_count);
                    v.setTag(holder);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            } else
                holder = (ViewHolder) v.getTag();

            String group_name = group_details.get(position).getGroup_name();
            holder.tv_group_name.setText(group_name);
            holder.tv_group_name.setTypeface(face);

            String groupRegId = group_details.get(position)
                            .getGroup_reg_id();
            holder.tv_group_reg_id.setText(groupRegId);
            holder.tv_group_reg_id.setTypeface(face);   

            holder.tv_subscriber_count.setText(group_details.get(position)
                            .getSubscriber_count());
            return v;

        }

Yes,you are right buddy.Thanks for the help and in future i will follow the standards and yes Paresh I will accept this answer in few mins.Thanks for the help. :) — codeRider, Jun 02 '14 at 13:05
This is the correct explanation for repeating items on scroll. Great. — user1947746, May 28 '16 at 02:56

score -1 · Answer 2 · edited Jun 20 '20 at 09:12

You may get nullpointerexception.. to get rid out of this try this simple code

 public View getView(int position, View convertView, ViewGroup parent) {
            final ViewHolder vh;
            View v = convertView;
            if(v == null){
                
                v = LayoutInflater.from(ctx).inflate(R.layout.simple_list_item, parent, false);
                vh = new ViewHolder(v);
                v.setTag(vh);
            }
            else{
                vh = (ViewHolder) v.getTag();
            }
    
            vh.tvTitle.setText(list.get(position).toString());
            return v;
        }
    
        class ViewHolder{
            TextView tvTitle;
    
            public ViewHolder(View v){
                tvTitle = (TextView) v.findViewById(R.id.tvVideoName);
            }

Repeating items in ListView?

2 Answers2

Wrong:

Correct:

You may get nullpointerexception.. to get rid out of this try this simple code

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