How to pass onClickHandler as parameter while setting adapter for a RecyclerView in a Fragment?

Question

I made an Adapter for my recyclerView. This adapter works when I use on any xxxActivity.java but when I try to use is on a Fragment Its hows error. Doesn't let me Pass the onClickHandler() that I created in Adapter. I am Setting Adapter Like this -

events_recyclerview.setAdapter(new FixedPlaceListAdapter(getContext(), placelist, mClickHandler)); //ClickListener doesn't work :'(

Another try was like --

events_recyclerview.setAdapter(new FixedPlaceListAdapter(getContext(), placelist, getmClickHandler()));

Here, I implemented getClickHandler() in the Fragment--

public FixedPlaceListAdapter.FixedPlaceListAdapterOnclickHandler getmClickHandler() {
    return mClickHandler;
}   //Still doesn't work :'(

and the Adapter Part-- Constructor like this-

public FixedPlaceListAdapter(Context mContext, List<PlaceBean> 
placeBeanList, FixedPlaceListAdapterOnclickHandler mClickHandler) {
    this.mContext = mContext;
    this.placeBeanList = placeBeanList;
    this.mClickHandler = mClickHandler;
}

I tried to do this ... but still doesn't work--

events_recyclerview.setAdapter(new FixedPlaceListAdapter(getContext(), placelist, FixedPlaceListAdapter.FixedPlaceListAdapterOnclickHandler.mClickhandler));

here is my full adapter code-

public class FixedPlaceListAdapter extends RecyclerView.Adapter<FixedPlaceListAdapter.FixedPlaceListAdapterViewHolder> {

private final FixedPlaceListAdapterOnclickHandler mClickHandler;
Context mContext;
List<PlaceBean> placeBeanList;

public FixedPlaceListAdapter(Context mContext, List<PlaceBean> placeBeanList, FixedPlaceListAdapterOnclickHandler mClickHandler) {
    this.mContext = mContext;
    this.placeBeanList = placeBeanList;
    this.mClickHandler = mClickHandler;
}

public void setData(List<PlaceBean> placeBeanList) {
    this.placeBeanList = placeBeanList;
    notifyDataSetChanged();
}

@Override
public FixedPlaceListAdapterViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    LayoutInflater inflater = LayoutInflater.from(mContext);
    View view = inflater.inflate(R.layout.top_list_single, parent, false);
    return new FixedPlaceListAdapterViewHolder(view);
}

@Override
public void onBindViewHolder(FixedPlaceListAdapterViewHolder holder, int position) {
    PlaceBean pb = placeBeanList.get(position);
    holder.nameTextView.setText(pb.getName());
    holder.addressTextView.setText(pb.getVicinity());
    holder.rating.setRating(pb.getRating());

    if (pb.getPhotoref() != null) {
        String imageUrl = UrlsUtil.getSinglePhotoUrlString(mContext, pb.getPhotoref(), "350", "300");
        Picasso.with(mContext)
                .load(imageUrl)
                .into(holder.thumbnailImage);
    }
}

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

public interface FixedPlaceListAdapterOnclickHandler {
    void onClick(String id);
}

public class FixedPlaceListAdapterViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

    TextView nameTextView;
    TextView addressTextView;
    RatingBar rating;
    ImageView thumbnailImage;

    public FixedPlaceListAdapterViewHolder(View itemView) {
        super(itemView);
        nameTextView = (TextView) itemView.findViewById(R.id.place_name_now_in_list);
        addressTextView = (TextView) itemView.findViewById(R.id.address_in_list);
        rating = (RatingBar) itemView.findViewById(R.id.rating_single_place_in_list);
        thumbnailImage = (ImageView) itemView.findViewById(R.id.place_image_thumb);
        itemView.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        String placeID = placeBeanList.get(getAdapterPosition()).getPlaceref();
        mClickHandler.onClick(placeID);
    }
}

}

Need Help!

Answer 1

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

    private List<CategoryNews> actors = new ArrayList<>();
    private Context mContext;

    private Queue<List<CategoryNews>> pendingUpdates =
            new ArrayDeque<>();

    **public interface NewsItemClickListener {
        void onNewsItemClick(int pos, CategoryNews categoryNews, ImageView shareImageView);
    }**

    **NewsItemClickListener newsItemClickListener;**

    public CategoryNewsListAdapter(List<CategoryNews> personList, Context mContext, NewsItemClickListener newsItemClickListener) {
        this.actors.addAll(personList);
        this.mContext = mContext;
        this.newsItemClickListener = newsItemClickListener;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        final LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        final View view = inflater.inflate(R.layout.particular_cat_news_list_row, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        Log.d("BusinessSubCategoryListAdapter", "Bindviewholder without payload");
        final CategoryNews newsCategory = actors.get(position);
        holder.news_title.setText(newsCategory.getPostTitle());
        holder.news_date.setText(newsCategory.getPostDate());
        holder.news_category.setText(newsCategory.getCategoryName());
        holder.news_description.setText(newsCategory.getPostContent());
//        GlideApp
//                .with(mContext).load(newsCategory.getPostImage())
//                .placeholder(R.mipmap.ic_launcher) // can also be a drawable
//                .error(R.drawable.placeholder_image) // will be displayed if the image cannot be loaded
//                .crossFade()
//                .into(holder.news_image);

        Picasso.with(mContext).load(newsCategory.getPostImage()).placeholder(R.drawable.placeholder_image).error(R.drawable.placeholder_image).into(holder.news_image);
**holder.itemView.setOnClickListener(v -> {
    newsItemClickListener.onNewsItemClick(position, newsCategory, holder.news_image);
});**

    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position, List<Object> payloads) {

        if (payloads.isEmpty()) {
            // if empty, do full binding;
            onBindViewHolder(holder, position);
            return;
        }
        Bundle bundle = (Bundle) payloads.get(0);

        String newTitle = bundle.getString("NAME_CHANGE");
        if (newTitle != null) {
            // add some animation if you want
            final CategoryNews actor = actors.get(position);
            holder.news_title.setText(actor.getPostTitle());
            holder.news_date.setText(actor.getPostDate());
            holder.news_category.setText(actor.getCategoryName());
            holder.news_description.setText(actor.getPostContent());
        }
    }

    public void addItems(List<CategoryNews> newItems) {
        // record this value before making any changes to the existing list
        int curSize = getItemCount();
        // update the existing list
        actors.addAll(newItems);
        // curSize should represent the first element that got added
        // newItems.size() represents the itemCount
        notifyItemRangeInserted(curSize, newItems.size());
    }

    public void updtateItems(List<CategoryNews> newItems) {
        // record this value before making any changes to the existing list
        int curSize = getItemCount();
        // update the existing list
        actors.addAll(newItems);
        // curSize should represent the first element that got added
        // newItems.size() represents the itemCount
        notifyItemRangeInserted(0,newItems.size()- getItemCount()-1);

    }



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

    public static class ViewHolder extends RecyclerView.ViewHolder {

        private TextView news_title, news_date, news_category, news_description;

        private ImageView news_image;

        public ViewHolder(View itemView) {
            super(itemView);
            news_title = (TextView) itemView.findViewById(R.id.news_title);
            news_date = (TextView) itemView.findViewById(R.id.news_date);
            news_category = (TextView) itemView.findViewById(R.id.news_category);
            news_description = (TextView) itemView.findViewById(R.id.news_description);
            news_image = (ImageView) itemView.findViewById(R.id.news_image);
        }
    }

}

And In your activity

1. implements NewsItemClickListener
2. create object NewsItemClickListener newsItemClickListner;
3. inside oncreate newsItemClickListner=this; (you mush have implemented 1)
4. pass that object to recyclerview.

In adapter it is received by this public CategoryNewsListAdapter(List personList, Context mContext, NewsItemClickListener newsItemClickListener) { this.actors.addAll(personList); this.mContext = mContext; this.newsItemClickListener = newsItemClickListener; }

In your activity

CategoryNewsListAdapter categoryNewsListAdapter= new CategoryNewsListAdapter(list,this,newsItemClickListner)

After doing all this your overriden method will be called when you click in item of recycler view where you have set onclick listner

Answer 2

Okay .. The Problem is Fixed now ... I was passing the wrong value or maybe the method of passing the ClickHandler was wrong. The Solution of the Problem : I Created another Class for ClickHandler-

 public class PlaceCardClickHandler implements 
 FixedPlaceListAdapter.FixedPlaceListAdapterOnclickHandler,
    PlaceListAdapter.PlaceListAdapterOnclickHandler {
Context mContext;

public PlaceCardClickHandler(Context mContext) {
    this.mContext = mContext;
}

@Override
public void onClick(String id) {
    Intent intentToStartDetail = new Intent(mContext, PlaceDetailActivity.class);
    intentToStartDetail.putExtra("id", id);
    mContext.startActivity(intentToStartDetail);
}

}

and the change in the Fragment was like this- (Just passed a object from the ClickHandler class)

 events_recyclerview.setAdapter(new FixedPlaceListAdapter(getContext(), placelist, new PlaceCardClickHandler(getContext())));