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Fragment, RecyclerView: No adapter attached; skipping layout

I am using a Fragment to view a RecyclerView. But I always get this error
E/RecyclerView: No adapter attached; skipping layout
I have created an adapter for my recyclerview but the layout does not display. The php backend is working fine. Can somebody please help. Here are my codes for the fragment and adapter
Tips.java
public class Tips extends Fragment {
Configuration config = new Configuration();
String HttpUrl = config.viewtips_url;
List<TipModel> tipList;
RecyclerView recyclerView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_tips, container, false);
recyclerView = view.findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
tipList = new ArrayList<>();
loadTips();
return view;
}
private void loadTips() {
StringRequest stringRequest = new StringRequest(Request.Method.GET, HttpUrl,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONArray jsonArray = new JSONArray(response);
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
tipList.add(new TipModel(
jsonObject.getInt("id"),
jsonObject.getString("tip")
));
}
TipAdapter tipAdapter = new TipAdapter(getActivity(), tipList);
recyclerView.setAdapter(tipAdapter);
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
Volley.newRequestQueue(getActivity()).add(stringRequest);
}
TipAdapter.java
public class TipAdapter extends RecyclerView.Adapter<TipAdapter.TipViewHolder> {
private Context context;
private List<TipModel> tipList;
public TipAdapter(Context context, List<TipModel> tipList) {
this.context = context;
this.tipList = tipList;
}
#Override
public TipViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(context);
View view = inflater.inflate(R.layout.itemlayout, null);
return new TipViewHolder(view);
}
#Override
public void onBindViewHolder(TipViewHolder holder, int position) {
TipModel tipModel = tipList.get(position);
holder.textViewTip.setText(tipModel.getTip());
}
#Override
public int getItemCount() {
return tipList.size();
}
class TipViewHolder extends RecyclerView.ViewHolder {
TextView textViewTip;
public TipViewHolder(View view) {
super(view);
textViewTip = view.findViewById(R.id.textViewTip);
}
}

It happens because RecyclerView is expecting an adapter when dispatching layout on view created, so it is fine if there is no adapter when the view is created, it will just skip the layout part.
If you are worried about the error, then you could set an empty adapter when the view is created:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_tips, container, false);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
recyclerView = view.findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
tipList = new ArrayList<>();
recyclerView.setAdapter(new TipAdapter(getActivity(), tipList));
}
Then adjust your code in the response callback:
#Override
public void onResponse(String response) {
// Instead of setting adapter here...
// TipAdapter tipAdapter = new TipAdapter(getActivity(), tipList);
// recyclerView.setAdapter(tipAdapter);
// Just notify the adapter that tipList has changed.
recyclerView.getAdapter().notifyDataSetChanged();
// ...
}

TipList is the Adapter's datastore, it belongs to the Adapter and not to the Fragment
I have edited your code ( don't have access to Android Studio, doing it in Text Editor, please check for syntax errors )
Fragment
public class Tips extends Fragment {
Configuration config = new Configuration();
String HttpUrl = config.viewtips_url;
RecyclerView recyclerView;
TipAdapter tipAdapter;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Initialize the Tip Adapter
tipAdapter = new TipAdapter(getActivity());
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_tips, container, false);
recyclerView = view.findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
// Assign the Adapter to recyclerView
recyclerView.setAdapter(tipAdapter);
return view;
}
private void loadTips() {
StringRequest stringRequest = new StringRequest(Request.Method.GET, HttpUrl,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONArray jsonArray = new JSONArray(response);
// Create a new TipList
List<TipModel> tipList = new ArrayList<>();
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
tipList.add(new TipModel(
jsonObject.getInt("id"),
jsonObject.getString("tip")
));
}
tipAdapter.updateWith(tipList)
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
Volley.newRequestQueue(getActivity()).add(stringRequest);
}
TipAdapter
public class TipAdapter extends RecyclerView.Adapter<TipAdapter.TipViewHolder> {
private Context context;
private List<TipModel> tipList = new ArrayList<>();
public TipAdapter(Context context) {
this.context = context;
}
#Override
public TipViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(context);
View view = inflater.inflate(R.layout.itemlayout, null);
return new TipViewHolder(view);
}
#Override
public void onBindViewHolder(TipViewHolder holder, int position) {
TipModel tipModel = tipList.get(position);
holder.textViewTip.setText(tipModel.getTip());
}
#Override
public int getItemCount() {
return tipList.size();
}
class TipViewHolder extends RecyclerView.ViewHolder {
TextView textViewTip;
public TipViewHolder(View view) {
super(view);
textViewTip = view.findViewById(R.id.textViewTip);
}
}
public updateWith(List<TipModel> tipList) {
this.tipList = tipList;
notifyDataSetChanged();
}

This is how I did it, when I had a similar problem while inflating recycler view in fragment. This code worked perfectly for me:
P.S. - This is the patch of code what I used in my application. I am sorry for any inconvenience.
First of all, in the onCreateView() of your Display Fragment:
public View onCreateView(#NonNull LayoutInflater inflater,
ViewGroup container, Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.fragment_home, container, false);
Firebase.setAndroidContext(getActivity());
((Home_Drawer) getActivity())
.setActionBarTitle("Home");
recyclerView = (RecyclerView) root.findViewById(R.id.recycler_view_home_frag);
progressBar = (ProgressBar) root.findViewById(R.id.mainPageProgressBar);
// Log.i("inside", "rv initiated" +mLayoutManager.toString());
// Assign activity this to progress dialog.
progressDialog = new ProgressDialog(getActivity());
// Setting up message in Progress dialog.
progressDialog.setMessage("Loading Images From Firebase.");
// Showing progress dialog.
progressDialog.show();
// The path is already defined in MainActivity.
databaseReference = FirebaseDatabase.getInstance().getReference().child("productDisplay");
Log.i("inside", databaseReference.toString());
return root;
}
Then, we call onStart(). This is because recycler view generally does not inflate, ehile setting the adapter in onCreateView().
#Override
public void onStart() {
super.onStart();
FirebaseRecyclerOptions<DisplayItemsModel> item_info =
new FirebaseRecyclerOptions.Builder<DisplayItemsModel>()
.setQuery(databaseReference, DisplayItemsModel.class)
.build();
final FirebaseRecyclerAdapter<DisplayItemsModel, ViewHolder> info_adapter =
new FirebaseRecyclerAdapter<DisplayItemsModel, ViewHolder>(item_info) {
#Override
protected void onBindViewHolder(final ViewHolder holder, final int position, final DisplayItemsModel model) {
mContext = getContext();
final DatabaseReference dref = getRef(position).getRef();
Log.i("dref", dref.toString());
// Adding Add Value Event Listener to databaseReference.
dref.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(final DataSnapshot snapshot) {
holder.item_name_single_card.setText(snapshot.child("name").getValue().toString());
holder.price_single_card.setText(snapshot.child("price").getValue().toString());
String image_url = snapshot.child("image").getValue().toString();
Picasso.get().load(image_url).into(holder.thumbnail);
// Continue with your code.
This worked perfectly for me. Hope it solves your problem.

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.

my recycler view in a fragments adapter getitem count showing zero,and not showing values in layout.but i add data to model class from api

homepageThis is my fragment class
public class Premiums extends Fragment {
private RecyclerView recyclerPremium;
private RecyclerView.LayoutManager mLayoutManager;
private List<FeaturedAddDetails> featuredAddDetailsList = new ArrayList<>();
private List<PremiumDetails> premiumDetailslist = new ArrayList<>();
private NewestAdapter newestAdapter;
private PremiumAdapter premiumAdapter;
private String jsonResponse;
private PremiumDetails premiumDetails;
private JSONObject jsonobject;
public Premiums() {
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View mainView = inflater.inflate(R.layout.premium_fragment, container, false);
recyclerPremium = (RecyclerView) mainView.findViewById(R.id.recycler_premium);
premiumAdd();
premiumAdapter = new PremiumAdapter(getActivity().getApplicationContext(), premiumDetailslist);
recyclerPremium.setAdapter(premiumAdapter);
return mainView;
}
#Override
public void onViewCreated(View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
mLayoutManager = new LinearLayoutManager(getContext(), LinearLayoutManager.VERTICAL, false);
recyclerPremium.setLayoutManager(mLayoutManager);
recyclerPremium.setHasFixedSize(true);
}
private void premiumAdd() {
PremiumRequestHandler premiumHandler = new PremiumRequestHandler("premiumADD");
premiumHandler.executeAsStringRequest(new Response.Listener<String>() {
#Override
public void onResponse(String response) {
Log.e("response", response);
JSONArray jsonarray = null;
try {
jsonarray = new JSONArray(response);
} catch (JSONException e) {
e.printStackTrace();
}
for (int i = 0; i < jsonarray.length(); i++) {
try {
jsonobject = jsonarray.getJSONObject(i);
Log.e("id", String.valueOf(jsonobject.getInt("id")));
premiumDetails = new PremiumDetails(jsonobject.getInt("id"),
jsonobject.getInt("userid"),
jsonobject.getInt("mobile"),
jsonobject.getInt("cityid"),
jsonobject.getInt("price"),
jsonobject.getInt("comments"),
jsonobject.getInt("created"),
jsonobject.getInt("categoryid"),
jsonobject.getInt("MainCategoryID"),
jsonobject.getInt("views"),
jsonobject.getInt("ImageCount"),
jsonobject.getInt("storeid"),
jsonobject.getString("title"),
jsonobject.getString("default_photo"),
jsonobject.getString("CityName"),
jsonobject.getString("CategoryName"),
jsonobject.getString("currency"),
jsonobject.getString("description"));
premiumDetailslist.add(premiumDetails);
premiumAdapter.setPremiumDetails(premiumDetailslist);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}, new BaseRequest.ErrorResponseCallback() {
#Override
public void onError(Exception exception) {
}
});
}
This is my adapter class
public class PremiumAdapter extends RecyclerView.Adapter<PremiumAdapter.MyViewHolderPremium> {
private List<PremiumDetails> premiumDetailsList;
private ImageLoader imageLoader;
private Context context;
public PremiumAdapter(Context context, List<PremiumDetails> premiumDetailsList) {
this.premiumDetailsList = premiumDetailsList;
this.context = context;
notifyDataSetChanged();
}
public void setPremiumDetails(List<PremiumDetails> premiumDetailsList) {
this.premiumDetailsList = premiumDetailsList;
notifyDataSetChanged();
}
public class MyViewHolderPremium extends RecyclerView.ViewHolder {
private TextView txtTitle,txtDescription,txtCityName,txtPrice,txtCategory,txtHour,txtPhotoNo;
private NetworkImageView imgPhoto;
public MyViewHolderPremium(View itemView) {
super(itemView);
txtTitle = (TextView)itemView.findViewById(R.id.txt_title_fad);
txtDescription = (TextView)itemView.findViewById(R.id.description_fad);
txtCityName = (TextView)itemView.findViewById(R.id.city_name_fad);
txtPrice = (TextView)itemView.findViewById(R.id.price_fad);
txtCategory = (TextView)itemView.findViewById(R.id.category_fad);
txtHour = (TextView)itemView.findViewById(R.id.hours_fad);
txtPhotoNo = (TextView)itemView.findViewById(R.id.txt_photo_no_fad);
imgPhoto=(NetworkImageView)itemView.findViewById(R.id.img_photo_lod_fad);
}
}
#Override
public MyViewHolderPremium onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.featured_ad_adapter_layout,parent,false);
final MyViewHolderPremium myViewHolderPremium = new MyViewHolderPremium(itemView);
return myViewHolderPremium;
}
#Override
public void onBindViewHolder(MyViewHolderPremium holder, int position) {
PremiumDetails premiumDetails = premiumDetailsList.get(position);
holder.txtTitle.setText(premiumDetails.getTitle());
holder.txtDescription.setText(premiumDetails.getDescription());
holder.txtCityName.setText(premiumDetails.getCityName());
holder.txtPrice.setText(Integer.toString(premiumDetails.getPrice()));
holder.txtCategory.setText(premiumDetails.getCategoryName());
holder.txtHour.setText(Integer.toString(premiumDetails.getCreated()));
holder.txtPhotoNo.setText(Integer.toString(premiumDetails.getImageCount())+" photos " );
try {
imageLoader= VolleyHandler.getImageLoader();
} catch (Exception e) {
e.printStackTrace();
}
//imageLoader = CustomVolleyRequest.getInstance(context).getImageLoader();
//imageLoader.get(featuredAddDetails.getDefault_photo(), ImageLoader.getImageListener(holder.imgPhoto, R.mipmap.ic_launcher, android.R.drawable.ic_dialog_alert));
holder.imgPhoto.setImageUrl(premiumDetails.getDefault_photo(),imageLoader);
}
#Override
public int getItemCount() {
Log.e("size", String.valueOf(premiumDetailsList.size()));
return premiumDetailsList.size();
}}
I am getting error on showing values but I got values from json and I can't add it to adapter and model class, plz help me I look stackoverflow whole day but I can't find my issue
my getItemCount() is showing as 0"

You are setting the adapter and then you are calling premiumAdd() method.First call that method and then set the adapter.
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View mainView = inflater.inflate(R.layout.premium_fragment, container, false);
recyclerPremium = (RecyclerView) mainView.findViewById(R.id.recycler_premium);
premiumAdd();
premiumAdapter = new PremiumAdapter(getActivity().getApplicationContext(), premiumDetailslist);
recyclerPremium.setAdapter(premiumAdapter);
return mainView;

Try notifyDataSetChanged() after setting data in the Constructor of your Adapter
[EDIT] Whenever your data changes, you need to inform your Adapter about it also, then call notifyDataSetChanged() on it.
You are probably setting empty data into the Adapter, your List changes, but the Adapter does not know about it.
[Update]
In addition to your Adapter constructor, add a setData(List) to your adapter to change your dataset at runtime.
public void setPremiumDetails(List<PremiumDetails> premiumDetailsList) {
this.premiumDetailsList = premiumDetailsList;
notifyDataSetChanged();
}
When your request in premiumAdd() returns, and you receive a new set of data, you call setPremiumDetails on your Adapter with the new data and the List will update.

#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View mainView = inflater.inflate(R.layout.premium_fragment, container, false);
recyclerPremium = (RecyclerView) mainView.findViewById(R.id.recycler_premium);
mLayoutManager = new LinearLayoutManager(getContext(), LinearLayoutManager.VERTICAL, false);
recyclerPremium.setLayoutManager(mLayoutManager);
recyclerPremium.setHasFixedSize(true);
premiumAdd();
premiumAdapter = new PremiumAdapter(getActivity().getApplicationContext(), premiumDetailslist);
recyclerPremium.setAdapter(premiumAdapter);
return mainView;
}
and remove premiumAdapter.notifyDataSetChanged();
added adapter code:
public class RVAdapter extends RecyclerView.Adapter<RVAdapter.ViewHolder> {
ArrayList<Model> dataset;
public RVAdapter(ArrayList<Model> dataset) {
this.dataset = dataset;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.rv_item,parent,false);
return new ViewHolder(v);
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
Model model = dataset.get(position);
holder.name.setText(model.name) ;
holder.status.setText(model.status);
if (model.status.equalsIgnoreCase("good"))
holder.ivStatus.setImageResource(R.drawable.ic_tick_48);
else
holder.ivStatus.setImageResource(R.drawable.ic_delete_48);
}
#Override
public int getItemCount() {
Log.e("TAG","SIZE: "+dataset.size());
return dataset.size();
}
public static class ViewHolder extends RecyclerView.ViewHolder {
TextView name;
TextView status;
ImageView ivStatus;
RelativeLayout parent;
public ViewHolder(View itemView) {
super(itemView);
name = (TextView) itemView.findViewById(R.id.rv_item_name);
status = (TextView) itemView.findViewById(R.id.rv_item_status);
ivStatus = (ImageView) itemView.findViewById(R.id.rv_item_iv);
parent = (RelativeLayout) itemView.findViewById(R.id.rv_item_parent);
}
}
}

your notifiy adapter on every single add
for (...){
....
premiumDetailslist.add(premiumDetails);
premiumAdapter.notifyDataSetChanged();// called every time wrong
}
also provide what exact error log says
and move the notifyDataSetChanged() after the for not in the loop
if no data is showing try recyclerview.invalidate , but i wont particularly do that way, would try debugging, log every step, inspect with method in the expected sequence isnt working

Recyclerview in fragmnet using volley json data?

please any one explain RecyclerView in fragment using volley to get json data.
Already i refered below link coding Google recyclerview in fragment
this is my first project in android, so i cannot understand that coding.
Please any one help me.
My fragmnet Coding:
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View drawer = inflater.inflate(R.layout.fragment_progress, container, false);
orderLists = new ArrayList<>();
getProgressData();
recyclerView = (RecyclerView) drawer.findViewById(R.id.progress);
adapter = new ProgressOrderListAdapter(orderLists, this);
adapter.clearAdaptor();
recyclerView.setAdapter(adapter);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
return recyclerView;
}
private void getProgressData(){
String mobilecustomertoken = SharedPreferencesManager.readPreferenceString("MobileCustomerToken", "D/N");
JSONObject progressData = new JSONObject();
try{
progressData.put("mobilecustomertoken", mobilecustomertoken);
JsonObjectRequest progressObject = new JsonObjectRequest(1, Common.OrderDetails + "progress", progressData, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject progressResponse) {
Log.d("Responseprogress", progressResponse.toString());
try {
int status = progressResponse.getInt("status");
if(status == 1) {
progressOrderProgress(progressResponse);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
Log.d("Response", "PROGRESS ERROR");
}
});
progressObject.setShouldCache(false);
ServiceBellApp.getInstance().addToRequestQueue(progressObject);
}
catch (JSONException localJSONException){
localJSONException.printStackTrace();
return;
}
}
private void progressOrderProgress(JSONObject progressResponse) throws JSONException {
JSONArray result = progressResponse.getJSONArray("orderdata");
OrderList orderListModule = new OrderList();
for(int i=0; i<result.length(); i++){
JSONObject orderData = result.getJSONObject(i);
orderListModule.setPackage_name(orderData.getString("package_name"));
orderListModule.setOrderdate(orderData.getString("orderdate"));
orderListModule.setServicedate(orderData.getString("servicedate"));
orderListModule.setServicetime(orderData.getString("servicetime"));
orderListModule.setOrderid(orderData.getString("orderid"));
orderListModule.setOrdstatus(orderData.getString("ordstatus"));
orderListModule.setOrderamount(orderData.getInt("orderamount"));
}
orderLists.add(orderListModule);
}
My adapter code:
public class OrderListAdapter extends RecyclerView.Adapter<OrderListAdapter.ViewHolder> {
List<OrderList> List;
private FragmentPending mContext;
public OrderListAdapter(List<OrderList> List, FragmentPending context) {
this.mContext = context;
this.List = List;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.order_list_view, null);
ViewHolder holder = new ViewHolder(view);
// this is where the each item is inflated.
return holder;
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
OrderList orderListsPos = List.get(position);
// this is where the data for each item is assigned
holder.textViewPackageName.setText(orderListsPos.getPackage_name());
holder.textOrderdate.setText(orderListsPos.getOrderdate());
holder.textServicedate.setText(orderListsPos.getServicedate());
holder.textServicetime.setText(orderListsPos.getServicetime());
holder.textOrderid.setText(orderListsPos.getOrderid());
holder.textOrderamount.setText("Rs." + orderListsPos.getOrderamount());
holder.textStatus.setText(orderListsPos.getOrdstatus());
}
#Override
public int getItemCount() {
return List.size();
}
public void clearAdaptor() {
List.clear();
}
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView textViewPackageName;
public TextView textServicedate;
public TextView textServicetime;
public TextView textOrderdate;
public TextView textOrderid;
public TextView textOrderamount;
public TextView textStatus;
public ViewHolder(View itemView) {
super(itemView);
textViewPackageName = (TextView) itemView.findViewById(R.id.productName);
textOrderdate = (TextView) itemView.findViewById(R.id.orderdate);
textOrderid = (TextView) itemView.findViewById(R.id.orderno);
textOrderamount = (TextView) itemView.findViewById(R.id.orderprice);
textStatus = (TextView) itemView.findViewById(R.id.orderstatus);
}
}}

First you need four things
1 ) layout that holds the each recycler view layout item
2 ) A view holder for creating each layout
3 ) A Model Class to holds the data
4 ) Recycler Adaptor which deals with the data for the Each Layout item
FIrst create a layout item
for eample lets create a single view with only TextView in it
XML
each_item.xml
<TextView
android:id="#+id/name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="2dp"
android:gravity="start|center_vertical"
android:textColor="#color/white"
android:textSize="18sp" />
and lets now create a view holder
i will post both code for the view holder and RecyclerAdaptor
public class Adaptor extends RecyclerView.Adapter<Adaptor.ViewHolder> {
List<Model> List = Collections.emptyList();
private Context mContext;
private LayoutInflater inflater;
public Adaptor(Context context, List<Model> List) {
inflater = LayoutInflater.from(context);
this.mContext = context;
this.List = List;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = inflater.inflate(R.layout.each_item, parent, false);
final ViewHolder holder = new ViewHolder(view);
// this is where the each item is inflated.
return holder;
}
#Override
public void onBindViewHolder(WinnersViewHolder holder, int position) {
Model mModel = List.get(position);
// this is where the data for each item is assigned
holder.nameView.setText("" + mModel.getName());
}
#Override
public int getItemCount() {
return List.size();
}
public void clearAdaptor() {
List.clear();
}
public class ViewHolder extends RecyclerView.ViewHolder {
protected TextView nameView;
public ViewHolder(View itemView) {
super(itemView);
this.nameView = (TextView) itemView.findViewById(R.id.name);
}
}
}
Now the model class
public class Model {
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name= name;
}
}
Now the back end is done, Lets implement it on the Fragment
List<Model> List = new ArrayList<>();
private RecyclerView mRecyclerView;
private Adaptor adaptor;
public Fragment() {
// constructor of fragment
// Required empty public constructor
}
in the onCreatView() get the id of recyclerView
View fragmentView = inflater.inflate(R.layout.fragment_layout, container, false);
mRecyclerView = (RecyclerView) fragmentView .findViewById(R.id.recycler_view);
and then pass the data to the Adaptor by creating its object
adaptor = new Adaptor(getContext(), List);
adaptor.clearAdaptor();
mRecyclerView.setAdapter(adaptor);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false));
You are done now, only thing pending is if you are accessing data form server call notifyDataSetChanged() or adaptor = new Adaptor(getContext(), getList()); where the getList() returns the Model data and do not call adaptor.clearAdaptor() .
hope this helps ..
EDIT
you can two ways infalte the each layout item .. one is above and second is in onCreateViewHolder
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.each_item, null);

Check this link It is really helpful for beginners for understanding concepts from start to mastering the RecyclerView.
https://github.com/codepath/android_guides/wiki/Using-the-RecyclerView
Hope this helps you to understand recycler view concepts.

RecycerView + Fragment + Volley
Fragment Code:
public class DogListFragment extends Fragment{
private RecyclerView rv;
private StaggeredGridLayoutManager llm;
private DogListAdapter adapter;
private ArrayList<DogModel> dogList;
private Context context;
public static DogListFragment getInstance(){
return new DogListFragment();
}
#Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
dogList = new ArrayList<>();
adapter = new DogListAdapter(context, dogList, this);
getListFromServer();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup parent, Bundle savedInstanceState){
View view = inflater.inflate(R.layout.fragment_dog_list, parent, false);
rv = view.findViewById(R.id.rv);
llm = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);
rv.setLayoutManager(llm);
rv.setAdapter(adapter);
return view;
}
public void getListFromServer(){
String url = "https://dog.ceo/api/breed/hound/images/random/20";
RequestQueue requestQueue = Volley.newRequestQueue(context);
StringRequest request = new StringRequest(Request.Method.GET, url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject jsonObject = new JSONObject(response);
JSONArray array = jsonObject.getJSONArray("message");
for(int i=0;i<array.length();i++){
String imageUrl = array.getString(i);
dogList.add(new DogModel(imageUrl));
}
adapter.updateDataSet(dogList);
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
}
);
requestQueue.add(request);
}
}
Full code
Woof Repository
It has the following implementations
Fragment communication via interface
Reusing fragment by
getSupportFragmentManager().findFragmentByTag(TAG)
Which lifecycle method should have API call so that it is called just
once
How to save RecylcerView state in Fragment (Scroll position + content)
Pagination in RecyclerView
Rest Calls (Volley)
Image Rendering (Glide)
JSON Parsing

adapter.setNotifyDatachanged() is not working as expected in android

This is my code file.
public class FragmentOfferList extends ListFragment {
private RecyclerView recyclerView;
private String TAG = FragmentOfferList.class.getSimpleName();
private static final String endpoint = "http://example.com/offer/offers.json";
private List<Offer> offers = new ArrayList<>();
private ProgressDialog pDialog;
RecyclerView.Adapter adapter;
public FragmentOfferList() {
}
public static FragmentOfferList newInstance(int num) {
FragmentOfferList f = new FragmentOfferList();
// Supply num input as an argument.
Bundle args = new Bundle();
args.putInt("num", num);
f.setArguments(args);
return f;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
pDialog = new ProgressDialog(getActivity());
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.recycler_list, container, false);
recyclerView = (RecyclerView) v.findViewById(R.id.recycler_view);
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
adapter = new MyAdapter(offers, getActivity());
recyclerView.setAdapter(adapter);
recyclerView.addOnItemTouchListener(new RecyclerTouchListener(getActivity(), recyclerView, new ClickListener() {
#Override
public void onClick(View view, int position) {
Offer offer = Utility.getOffers().get(position);
Intent intent = new Intent(getActivity(), ActivityProductList.class);
intent.putExtra("query", offer.getQuery());
startActivity(intent);
//startActivity(new Intent(getActivity(), ActivityProductList.class));
}
#Override
public void onLongClick(View view, int position) {
}
}));
if (Utility.getOffers().size() == 0){
fetchOffers();
}
else{
Utility.displayToast("here");
offers = Utility.getOffers();
adapter.notifyDataSetChanged();
}
return v;
}
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
private List<Offer> offers;
private Context context;
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView title, year, offer;
ImageView imageView;
public MyViewHolder(View view) {
super(view);
imageView = (ImageView) view.findViewById(R.id.thumbnail);
title = (TextView) view.findViewById(R.id.title);
offer = (TextView) view.findViewById(R.id.offer);
}
}
public MyAdapter(List<Offer> offers, Context context) {
this.offers = offers;
this.context = context;
}
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.card_offer, parent, false);
return new MyViewHolder(itemView);
}
#Override
public void onBindViewHolder(MyViewHolder holder, int position) {
Offer offer = offers.get(position);
holder.title.setText(offer.getName());
holder.offer.setText(offer.getOffer());
Glide.with(context).load(String.valueOf(offer.getUrl()))
.error(R.drawable.placeholder)
.thumbnail(0.5f)
.crossFade()
.diskCacheStrategy(DiskCacheStrategy.ALL)
.into(holder.imageView);
}
#Override
public int getItemCount() {
return offers.size();
}
}
private void fetchOffers() {
pDialog.setMessage("Downloading json...");
pDialog.show();
JsonArrayRequest req = new JsonArrayRequest(endpoint,
new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
Log.d(TAG, response.toString());
pDialog.hide();
offers.clear();
for (int i = 0; i < response.length(); i++) {
try {
JSONObject object = response.getJSONObject(i);
Offer offer = new Offer();
offer.setOffer(object.getString("offer"));
offer.setName(object.getString("name"));
offer.setUrl(object.getString("url"));
offer.setQuery(object.getString("query"));
offers.add(offer);
} catch (JSONException e) {
Log.e(TAG, "Json parsing error: " + e.getMessage());
}
}
Utility.setOffers(offers);
adapter.notifyDataSetChanged();
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Error: " + error.getMessage());
pDialog.hide();
}
});
// Adding request to request queue
AppController.getInstance().addToRequestQueue(req);
}
}
First time when Utility.getoffers().size() is 0, it fetches data, save it in Utility.setOffers(offers) and display on screen as expected. But next time (go back and to same activity), Utility.getoffers().size() is not 0 , i got data directly from Utility.getBrands().
After that i called adapter.notifyDataSetChaned(), but it is not working. Not working menas even though data sise is more than 0 but no data rendering on screen?
What is wrong here? am i missing anything?

You are not updating your offers list, but rather replacing it with another list that your adapter has no reference to. To fix this you can do the following:
offers.clear();
offers.addAll(Utility.getOffers());
adapter.notifyDataSetChanged();