How to prevent items from getting duplicated when

问题:

I have created a row inside recycler view and inside that I have inflated two rows or more but when I scroll the items are getting used again. I am not getting where to recycle view or remove them dynamically I need a feed and their comments.For comments I need to inflate layouts to display them below feeds for which getCommentInflaterView method is created.

But the view created using getCommentInflaterView() gets duplicated. MyAdapterClass:

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

    ArrayList<Data> arrayListAllFeedsData;
    Comment objComment;


    Context context;

    public AllFeedsAdapter(Context context, ArrayList<Data> data) {
        this.context = context;
        arrayListAllFeedsData = new ArrayList<>();
        arrayListAllFeedsData = data;
    }


    @Override
    public AllFeedsAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        Context context = parent.getContext();
        LayoutInflater inflater = LayoutInflater.from(context);

        // Inflate the custom layout
        View post_row_view = inflater.inflate(R.layout.row_teacher_post, parent, false);

        // Return a new holder instance
        ViewHolder viewHolder = new ViewHolder(post_row_view);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(AllFeedsAdapter.ViewHolder holder, int position) {

        holder.txtUsernamePostCreator.setText(arrayListAllFeedsData.get(position).getFull_name());
        holder.txtPostContent.setText(arrayListAllFeedsData.get(position).getFeed_text());
        holder.txtPostLikeCounter.setText(arrayListAllFeedsData.get(position).getTotal_like());
        holder.txtPostCommentsCounter.setText(arrayListAllFeedsData.get(position).getTotal_comment());

        if (arrayListAllFeedsData.get(position).getComment().size() > 0) {


            if (arrayListAllFeedsData.get(position).getComment().size() > 2) {
                for (int i = 0; i < 2; i++) {

                    objComment = arrayListAllFeedsData.get(position).getComment().get(i);

                    if (getCommentInflaterView(objComment) == null) {
                        holder.llCommentRowInflater.addView(getCommentInflaterView(objComment));
                    } else {
                        holder.llCommentRowInflater.removeAllViews();
                    }


                }
            } else {
                for (int i = 0; i < arrayListAllFeedsData.get(position).getComment().size(); i++) {

                    objComment = arrayListAllFeedsData.get(position).getComment().get(i);
                    if (getCommentInflaterView(objComment) == null) {
                        holder.llCommentRowInflater.addView(getCommentInflaterView(objComment));

                    } else {
                        holder.llCommentRowInflater.removeAllViews();
                    }

                }
            }

        }


    }

    private View getCommentInflaterView(Comment commentData) {

        LayoutInflater layoutInflater = LayoutInflater.from(context);
        View v = layoutInflater.inflate(R.layout.post_comments_list_item, null, false);

        TextView txtCommenterUsername = (TextView) v.findViewById(R.id.txt_username_commenter);
        TextView txtCommenterComment = (TextView) v.findViewById(R.id.txt_comments_from_commenter);
        TextView txtCommentDuration = (TextView) v.findViewById(R.id.txt_comment_duration);


        txtCommenterUsername.setText(commentData.getUsername());
        txtCommenterComment.setText(commentData.getComment());
        txtCommentDuration.setText(commentData.getCommentBy());


        return v;

    }

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

    /**
     * USed to create static class for all the view if listitem child
     */
    public static class ViewHolder extends RecyclerView.ViewHolder {
        // Your holder should contain a member variable
        // for any view that will be set as you render a row

        public LinearLayout llParentTeacherPost, llCommentRowInflater;

        // We also create a constructor that accepts the entire item row
        // and does the view lookups to find each subview
        public ViewHolder(View itemView) {
            // Stores the itemView in a public final member variable that can be used
            // to access the context from any ViewHolder instance.
            super(itemView);
            llParentTeacherPost = (LinearLayout) itemView.findViewById(R.id.ll_parent_teacher_post);
            llCommentRowInflater = (LinearLayout) itemView.findViewById(R.id.ll_comment_row_inflater);

            imgDpPostCreator = (ImageView) itemView.findViewById(R.id.img_dp_post_creator);
            txtUsernamePostCreator = (TextView) 
        }


    }
}

回答1:

Override these two methodes in adapter.

@Override
public long getItemId(int position) {
    return position;
}

@Override
public int getItemViewType(int position) {
   return position;
}

回答2:

inside your adapter class AllFeedsAdapter, you need to override the method:

@Override
public long getItemId(int position){
// return specific item's id here
}

回答3:

Worked for me Clear the content before loading the data in Recycler View

listOftrailers.clear();

回答4:

I was having this problem too. I can confirm adding getItemId and getItemViewType to the adapter solves the duplication of images in recyclerview items, when scrolling.

@Override
public long getItemId(int position) {
    return position;
}

@Override
public int getItemViewType(int position) {
   return position;
}

I would have left this as a comment, but I have less than 5 feedback.

回答5:

At the end of onBindViewHolder method, include: holder.itemView.setTag(arrayListAllFeedsData.get(position));