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recyclerview doesn't show any thing in fragment

hi guys i have a card view that populate it's data from a json. I parse json with volley and it is successfull .
but in card view there is nothing to show
here is my json
{"photo":[{"id":"4","profile_id":"mahdi","caption":"hello","image_url":"https:\/\/hemispheric-suggest.000webhostapp.com\/img\/img\/birjand.jpg","profile_img_url":"https:\/\/hemispheric-suggest.000webhostapp.com\/prof\/prof\/prof_1.jpg","insert_time":"2017-07-09 11:21:44"}
and my fragment adapter :
private RecyclerView recyclerView;
private RequestQueue mRequestQueue;
ArrayList<Card> list = new ArrayList<>();
String url = "My url";
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.frag,container,false);
recyclerView = (RecyclerView) view.findViewById(R.id.recycler);
mRequestQueue = Volley.newRequestQueue(getActivity());
list();
LinearLayoutManager MyLayoutManager = new LinearLayoutManager(getActivity());
MyLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView.setAdapter(new Adapter(list));
return view;
}
public class Adapter extends RecyclerView.Adapter<Adapter.MyviewHolder>{
// private ArrayList<Card> list;
public Adapter(ArrayList<Card> data) {
list = data;
}
public class MyviewHolder extends RecyclerView.ViewHolder{
public TextView textView;
public ImageView imageView;
public MyviewHolder(View itemView) {
super(itemView);
textView = (TextView) itemView.findViewById(R.id.textView);
imageView = (ImageView) itemView.findViewById(R.id.imageView);
}
}
#Override
public MyviewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.card_row,parent,false);
return new MyviewHolder(view);
}
#Override
public void onBindViewHolder(MyviewHolder holder, int position) {
Card card = list.get(position);
holder.textView.setText(card.getName());
Glide.with(getActivity()).load(card.getImg()).into(holder.imageView);
}
#Override
public int getItemCount() {
return list.size();
}
}
public void list() {
JsonObjectRequest object = new JsonObjectRequest(Request.Method.GET, url,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try{
JSONArray array = response.getJSONArray("photo");
for (int i = 0; i <array.length() ; i++) {
JSONObject temp = array.getJSONObject(i);
Card card = new Card();
card.setName(temp.getString("profile_id"));
card.setImg(temp.getString("image_url"));
list.add(card);
}
}catch (Exception ex){
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
}
);
mRequestQueue.add(object);
}
}

Volley is asynchronus, so when you call:
recyclerView.setAdapter(new Adapter(list));
just a few milliseconds after you enqueued your request, It's very likely that the list is still empty because Volley hasn't received any response yet. You should set your adapter once you get the response inside the onResponse callback.

RecyclerView dosent show any elements following is my code

Fragment_bookmovie2.java
public class Fragment_bookmovie2 extends android.support.v4.app.Fragment implements View.OnClickListener {
private static final String TAG ="Fragment_bookmovie2" ;
ArrayList<String> moviename= new ArrayList<>();
ArrayList<String> movieyear= new ArrayList<>();
ArrayList<String> moviebanner= new ArrayList<>();
private RecyclerView.LayoutManager layoutManager;
private static RecyclerView recyclerView;
Movie_listAdapter2 adapter ;
LinearLayout progress;
RelativeLayout ll;
public Fragment_bookmovie2() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Log.e(TAG,"reched on create");
// first step - retrieve object
Backendless.Persistence.of(Booking.class).find(new AsyncCallback<BackendlessCollection<Booking>>() {
#Override
public void handleResponse(BackendlessCollection<Booking> response) {
for(Booking booking : response.getData()) {
if(!moviename.contains(booking.getMovie().get(0).getMovie_Name())) {
moviename.add(booking.getMovie().get(0).getMovie_Name());
movieyear.add(booking.getMovie().get(0).getYear());
moviebanner.add("https://api.backendless.com/" + BackendSetting.APPLICATION_ID + "/" + BackendSetting.VERSION + "/files/mypics/" + booking.getMovie().get(0).getImage());
}
}
adapter.notifyDataSetChanged();
ll.removeView(progress);
}
#Override
public void handleFault(BackendlessFault fault) {
Toast.makeText(getActivity(), fault.getMessage(), Toast.LENGTH_SHORT).show();
}
});
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
moviename.add("haha");
movieyear.add("hello");
moviebanner.add("http://www.w3schools.com/css/trolltunga.jpg");
// Inflate the layout for this fragment
ll = (RelativeLayout) inflater.inflate(R.layout.fragment_bookmovie2, container, false);
progress = (LinearLayout) ll.findViewById(R.id.progress_bookingFrag);
recyclerView = (RecyclerView) ll.findViewById(R.id.recycle_movielist);
recyclerView.setHasFixedSize(true);
layoutManager = new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(layoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
adapter = new Movie_listAdapter2(getActivity(),moviename,movieyear,moviebanner);
recyclerView.setAdapter(adapter);
adapter.notifyDataSetChanged();
return ll;
}
#Override
public void onClick(View view) {
}
#Override
public void onPause() {
super.onPause();
}
#Override
public void onResume() {
super.onResume();
}
/*#Override
public void onButtonClickListnerProceed(Integer pos) {
Intent booking_screen_redirect = new Intent(getActivity(), BookingScreen2.class);
booking_screen_redirect.putExtra("movie_name",moviename.get(pos));
this.onPause();
startActivity(booking_screen_redirect);
getActivity().overridePendingTransition(R.anim.pull_in_right, R.anim.push_out_left);
}*/
}
Movie_listAdapter2.java
public class Movie_listAdapter2 extends RecyclerView.Adapter<Movie_listAdapter2.Movie_cards>{
final static String TAG="Movie_listAdapter2";
Context context_external;
ArrayList<String> moviename=new ArrayList<>();
ArrayList<String> movieyear=new ArrayList<>();
ArrayList<String> banner=new ArrayList<>();
public Movie_listAdapter2(Context context,ArrayList<String> resource, ArrayList<String> resource1, ArrayList<String> resource2) {
//set the context and the format of the layout inside the list item
//i.e R.layout.movie_list_adapter
//also the resource i.e the item names in an ArrayList
this.moviename = resource;
this.movieyear = resource1;
this.banner = resource2;
this.context_external=context;
Log.e(TAG,"size = "+movieyear.size()+" "+moviename.size());
}
public static class Movie_cards extends RecyclerView.ViewHolder {
CardView cv;
TextView movie_name;
TextView movie_year;
Button proceed;
ImageView movie_banner;
public Movie_cards(View itemView) {
super(itemView);
cv = (CardView)itemView.findViewById(R.id.movie_list_card);
movie_name = (TextView)itemView.findViewById(R.id.tv_card_moviename);
movie_year = (TextView)itemView.findViewById(R.id.tv_card_movieyear);
movie_banner = (ImageView)itemView.findViewById(R.id.card_moviebanner);
proceed = (Button) itemView.findViewById(R.id.b_card_proceed);
}
}
#Override
public Movie_cards onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.movie_list_card, parent, false);
Movie_cards pvh = new Movie_cards(v);
return pvh;
}
public void updateData(ArrayList<String> resource, ArrayList<String> resource1, ArrayList<String> resource2) {
this.moviename = resource;
this.movieyear = resource1;
this.banner = resource2;
notifyDataSetChanged();
}
#Override
public void onBindViewHolder(final Movie_cards holder, final int position) {
holder.movie_name.setText(moviename.get(position));
holder.movie_year.setText(movieyear.get(position));
Picasso.with(context_external)
.load(banner.get(position))
.placeholder(R.drawable.placeholder)
.networkPolicy(NetworkPolicy.OFFLINE)
.error(R.drawable.placeholder)
.fit()
.into(holder.movie_banner, new Callback() {
#Override
public void onSuccess() {
//i.e image was loaded from cache
}
#Override
public void onError() {
//image was downloaded as it wasn't available in cache
Picasso.with(context_external)
.load(banner.get(position))
.placeholder(R.drawable.placeholder)
.error(R.drawable.warning)
.fit()
.into(holder.movie_banner);
}
});
holder.proceed.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
Intent booking_screen_redirect = new Intent(context_external, BookingScreen2.class);
booking_screen_redirect.putExtra("movie_name",moviename.get(position));
context_external.startActivity(booking_screen_redirect);
//overridePendingTransition(R.anim.pull_in_right, R.anim.push_out_left);
}
});
}
#Override
public int getItemCount() {
return 0;
}
#Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
}
}
the fragment displays empty and no items appear even though i have added the data to arraylists and passed to the adapter. please help . thanks in advance

Problem is in below code you are returning 0 that's why its not showing any item
#Override
public int getItemCount() {
return 0;
}
You should return your list's size here either moviename.size(); or movieyear.size()

RecyclerView not populating inside fragment using volley

My recyclerview is not populating inside fragment. I am getting proper response from volley. I have parsed the JSON in arraylist in proper format only problem is that recyclerview is not populating.
MyFragment.java
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_undekha_tadka, container, false);
recyclerView = (RecyclerView) view.findViewById(R.id.recyclerView);
myVolleyOperation(view);
return view;
}
private void myVolleyOperation(View v) {
volleySingleton = VolleySingleton.getInstance();
requestQueue = volleySingleton.getRequestQueue();
String url = "http://abcd.com/undekha.html";
StringRequest stringRequest = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
jsonParsing(response);
Toast.makeText(getContext(), response, Toast.LENGTH_SHORT).show();
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getContext(), "ERROR\n" + error.toString(), Toast.LENGTH_SHORT).show();
}
});
requestQueue.add(stringRequest);
recyclerViewAdapter = new RecyclerViewAdapter(undekhaList, v.getContext());
layoutManager = new LinearLayoutManager(getContext());
recyclerView.setLayoutManager(layoutManager);
recyclerView.setAdapter(recyclerViewAdapter);
}
RecyclerViewAdapter.java
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.RecyclerViewHolder> {
ArrayList<UndekhaModel> myArrayList = new ArrayList<>();
Context context;
VolleySingleton volleySingleton;
ImageLoader imageLoader;
public RecyclerViewAdapter(ArrayList<UndekhaModel> myArrayList, Context context) {
this.myArrayList = myArrayList;
this.context = context;
volleySingleton = VolleySingleton.getInstance();
imageLoader = volleySingleton.getImageLoader();
}
#Override
public RecyclerViewAdapter.RecyclerViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.single_row, parent, false);
RecyclerViewHolder recyclerViewHolder = new RecyclerViewHolder(view, context, myArrayList);
return recyclerViewHolder;
}
#Override
public void onBindViewHolder(final RecyclerViewAdapter.RecyclerViewHolder holder, int position) {
UndekhaModel undekhaModel = myArrayList.get(position);
holder.title.setText(undekhaModel.getTitle());
String loadUrl = "http://img.youtube.com/vi/" + undekhaModel.getId() + "/0.jpg";
if (loadUrl!=null){
imageLoader.get(loadUrl, new ImageLoader.ImageListener() {
#Override
public void onResponse(ImageLoader.ImageContainer response, boolean isImmediate) {
holder.thumbnail.setImageBitmap(response.getBitmap());
}
#Override
public void onErrorResponse(VolleyError error) {
holder.thumbnail.setImageResource(R.mipmap.ic_launcher);
}
});
}
}
#Override
public int getItemCount() {
return myArrayList.size();
}
public static class RecyclerViewHolder extends RecyclerView.ViewHolder {
TextView title;
ImageView thumbnail;
ArrayList<UndekhaModel> modelArrayList = new ArrayList<>();
Context context;
public RecyclerViewHolder(View itemView, final Context ctx, final ArrayList<UndekhaModel> modelArrayList) {
super(itemView);
this.context = ctx;
this.modelArrayList = modelArrayList;
title = (TextView) itemView.findViewById(R.id.tvTitle);
thumbnail = (ImageView) itemView.findViewById(R.id.ivShow);
}
}
}

Your method jsonParsing() needs to populate data for your RecyclerViewAdapter, needs to notify of the update and the adapter needs to return the correct count of items it is managing. Right now its getItemCount() is always returning 0, so the RecyclerView does not think there is anything to show.

Same issue than here
https://stackoverflow.com/a/35802948/2144418
Try setting the adapter before the layout manager
Change the last two lines on myVolleyOperation to this
recyclerView.setAdapter(recyclerViewAdapter);
recyclerView.setLayoutManager(layoutManager);

Android Recycler View

I am using RecyclerView to display my products, problem is when if I select the first products and scroll down to the end of list I see different products selected and when i scroll back to top of list the first item is not selected.
My Adapter
public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.MyViewHolder> {
String u = "http://192.185.52.231/~sabby070/hyype/";
Context context1;
private java.util.List<ProductDetails> List;
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.view_list, parent, false);
return new MyViewHolder(itemView);
}
public RecyclerAdapter(List<ProductDetails> DataList, FragmentActivity activity) {
this.List = DataList;
context1 = activity;
}
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView Likecount;
public ImageView Image;
public ImageView Imagelike, ImageUnlike;
public MyViewHolder(View view) {
super(view);
Likecount = (TextView) view.findViewById(R.id.textView_itemPrice);
Image = (ImageView) view.findViewById(R.id.imageView_imgtosold);
Imagelike = (ImageView)view.findViewById(R.id.Like_Button);
ImageUnlike = (ImageView)view.findViewById(R.id.UnLike_Button);
}
}
#Override
public void onBindViewHolder(final RecyclerAdapter.MyViewHolder holder, final int position) {
final ProductDetails detail = List.get(position);
holder.Likecount.setText(detail.getLikeCount());
Glide.with(context1).load(u+detail.getImage()).override(600, 200).diskCacheStrategy(DiskCacheStrategy.ALL).into(holder.Image);
holder.Image.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Toast.makeText(context1, ""+position, Toast.LENGTH_SHORT).show();
Intent intent = new Intent(context1, Buy_Product.class);
intent.putExtra("Product Name",detail.getLikeCount());
intent.putExtra("Product Image",detail.getImage());
context1.startActivity(intent);
}
});
holder.Imagelike.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (holder.Imagelike.getVisibility()==View.VISIBLE)
{
holder.Imagelike.setVisibility(View.GONE);
holder.ImageUnlike.setVisibility(View.VISIBLE);
}
}
});
holder.ImageUnlike.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (holder.ImageUnlike.getVisibility()==View.VISIBLE)
{
holder.Imagelike.setVisibility(View.VISIBLE);
holder.ImageUnlike.setVisibility(View.GONE);
}
}
});
}
#Override
public int getItemCount() {
return List.size();
}
}
My class
public class Men_Fragment extends Fragment {
static String URL = "http://192.185.52.231/~sabby070/hyype/index.php?action=timeline&user_id=53&post_category=timeline";
private List<ProductDetails> DataList = new ArrayList<>();
private RecyclerView recyclerView;
private RecyclerAdapter rAdapter;
String img;
String a;
Boolean list[];
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_men_, container, false);
recyclerView = (RecyclerView) view.findViewById(R.id.men_recycler_view);
StringRequest stringRequest = new StringRequest(Request.Method.GET, URL, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
JSONObject jsonObject = null;
try {
jsonObject = new JSONObject(response);
for (int i = 0; i < response.length(); i++) {
JSONObject obj = jsonObject.getJSONObject(String.valueOf(i));
a = obj.getString("like_count");
img = obj.getString("video_thumb");
final ProductDetails details = new ProductDetails(a, img);
DataList.add(details);
rAdapter = new RecyclerAdapter(DataList, getActivity());
RecyclerView.LayoutManager mLayoutManager = new GridLayoutManager(getActivity(), 2);
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.setAdapter(rAdapter);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getActivity(), "" + error, Toast.LENGTH_SHORT).show();
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<String, String>();
return params;
}
};
RequestQueue requestQueue = Volley.newRequestQueue(getActivity());
requestQueue.add(stringRequest);
return view;
}
}

You have to take List(with boolean) and store selected values in that list and then use those values in onBindView()

In your ProductDetails class add a field boolean selected;
In your onClick() add List.get(position).setSelected(!List.get(position).isSelected()); to check/uncheck as needed.
Finaly in your onBindViewHolder(...) add
if(List.get(position).isSelected()){
holder.Imagelike.setVisibility(View.VISIBLE);
}else{
holder.ImageUnlike.setVisibility(View.GONE);
}

notify adapter after fetch new data

I have an adapter which won't get notified after fetching new data by Retrofit however, I'm using notifyDataSetChanged and get success in the logs but nothing works either :(
Also I tried to use local array with this adapter and it works great.
public class alberrClassNews extends Fragment {
private RecyclerView recyclerView;
private List<alberrNewsListContent> alberrNews = new ArrayList<alberrNewsListContent>();
private final String TAG = "Get JSONArray";
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.alberrnewsclass, container, false);
getActivity().setTitle("nnnn");
recyclerView = (RecyclerView) view.findViewById(R.id.alberrNewsList);
LinearLayoutManager layoutManager = new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(layoutManager);
layoutManager.setReverseLayout(true);
layoutManager.setStackFromEnd(true);
final alberrNewsAdapter aNA = new alberrNewsAdapter(getActivity(), alberrNews);
recyclerView.setAdapter(aNA);
final ProgressDialog progressDialog = new ProgressDialog(getActivity());
progressDialog.setMessage("loading");
progressDialog.show();
final Retrofit alberrRetrofit = new Retrofit.Builder()
.baseUrl("http://nn.com/abbn/")
.addConverterFactory(GsonConverterFactory.create()).build();
alberrService service = alberrRetrofit.create(alberrService.class);
Call<JSONArray> call = service.alberrNews();
call.enqueue(new Callback<JSONArray>() {
#Override
public void onResponse(Call<JSONArray> call, Response<JSONArray> response) {
progressDialog.dismiss();
Log.i(TAG, "success");
try{
JSONArray jsonArray = response.body().getJSONArray(0);
for (int i = 0 ; i < jsonArray.length() ; i++){
JSONObject jsonObject = jsonArray.getJSONObject(i);
alberrNewsListContent newsContent = new alberrNewsListContent();
newsContent.setAlberrNewsTitle(jsonObject.getString("title"));
newsContent.setAlberrNewsSubject(jsonObject.getString("subject"));
newsContent.setAlberrNewsImage(jsonObject.getString("image"));
alberrNews.add(newsContent);
}
} catch (JSONException e){
e.printStackTrace();
}
aNA.notifyDataSetChanged();
}
#Override
public void onFailure(Call<JSONArray> call, Throwable t) {
Log.i(TAG, "Failed");
progressDialog.dismiss();
Toast.makeText(getActivity().getApplicationContext(),
"no connection", Toast.LENGTH_SHORT).show();
}
});
return view;
}
Adapter Class
public class alberrNewsAdapter extends RecyclerView.Adapter<alberrNewsAdapter.ViewHolder> {
private List<alberrNewsListContent> newsListContent;
private Context context;
public alberrNewsAdapter(Context ncontext , List<alberrNewsListContent> nnewsListContent ){
this.context = ncontext;
this.newsListContent = nnewsListContent;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater
.from(parent.getContext())
.inflate(R.layout.alberrnewscontent, parent, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(alberrNewsAdapter.ViewHolder holder, int position) {
final alberrNewsListContent newsContent = newsListContent.get(position);
holder.alberrNewsTitle.setText(newsContent.getAlberrNewsTitle());
holder.alberrNewsSubject.setText(newsContent.getAlberrNewsSubject());
Glide.with(context)
.load(newsContent.getAlberrNewsImage())
.override(300, 260)
.into(holder.alberrNewsImage);
}
#Override
public int getItemCount() {
return newsListContent.size();
}
public void replaceDataSet(List<alberrNewsListContent> alberrNews){
this.newsListContent = alberrNews;
notifyDataSetChanged();
}
public static class ViewHolder extends RecyclerView.ViewHolder{
TextView alberrNewsTitle;
TextView alberrNewsSubject;
ImageView alberrNewsImage;
CardView alberrNewsCardView;
public ViewHolder(View itemView) {
super(itemView);
alberrNewsTitle = (TextView)itemView.findViewById(R.id.alberrNewsTitle);
alberrNewsSubject = (TextView)itemView.findViewById(R.id.alberrNewsSubject);
alberrNewsImage = (ImageView)itemView.findViewById(R.id.alberrNewsImage);
alberrNewsCardView = (CardView)itemView.findViewById(R.id.alberrNewsCardView);
}
}
}

In your alberrNewsAdapter, you can create a new method called replaceDataSet() which will replace your dataset in the adapter and call notifyDataSetChanged().
private List<alberrNewsListContent> alberrNews alberrNews;
public void replaceDataSet(List<alberrNewsListContent> alberrNews){
this.alberrNews = alberrNews;
notifyDataSetChanged();
}
And in onResponse() instead of calling aNA.notifyDataSetChanged(); call aNA.replaceDataSet();

Pass new list content to the adapter via public method and call notifyDataSetChanged(); inside that method. Currently, you're not updating the list inside the adapter.