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Android studio java can't get context in Fragment

I am absolute beginner for this, I'm sorry if this such a dumb mistakes.
so, I created fragment in which i have got recyclerView, but my recycler view is empty, i saw that my context is empty, and i think, that it can be the reason of this, i try to use getActivity
here is code of my fragment
package com.example.pocketcinema;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.fragment.app.Fragment;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.QueryDocumentSnapshot;
import com.google.firebase.firestore.QuerySnapshot;
import java.util.ArrayList;
import java.util.List;
public class SearchFragment extends Fragment implements RecyclerViewInterface {
private RecyclerView recyclerView;
RecyclerViewInterface rci;
MyAdapter myAdapter;
public List<String> nameOfFilm, youTubeUrl, photoUrl, descriptionToFilm, category;
FirebaseFirestore db = FirebaseFirestore.getInstance();
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
recyclerView = inflater.inflate(R.layout.fragment_search, container,
false).findViewById(R.id.filmsList);
rci = this;
nameOfFilm = new ArrayList<>();
youTubeUrl = new ArrayList<>();
photoUrl = new ArrayList<>();
descriptionToFilm = new ArrayList<>();
category = new ArrayList<>();
loadFilmsFromDB();
return inflater.inflate(R.layout.fragment_search, container, false);
}
private void loadFilmsFromDB() {
Context context = requireContext();
db.collection("films").get().addOnCompleteListener(new
OnCompleteListener<QuerySnapshot>()
{
#Override
public void onComplete(#NonNull Task<QuerySnapshot> task) {
for (QueryDocumentSnapshot document : task.getResult()) {
nameOfFilm.add(document.get("nameOfFilm").toString());
descriptionToFilm.add(document.get("descriptionToFilm").toString());
photoUrl.add(document.get("imageUrl").toString());
youTubeUrl.add(document.get("videoURL").toString());
category.add(document.get("category").toString());
myAdapter = new MyAdapter(context, nameOfFilm, descriptionToFilm,
photoUrl, youTubeUrl,
rci, category);
recyclerView.setAdapter(myAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(context));
}
}
});
}
here is screenshot with debuger, you can see that context = null
context = null
here you can see that i set layout for recyclerView
with logcat
here is Adapter
package com.example.pocketcinema;
import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.cardview.widget.CardView;
import androidx.recyclerview.widget.RecyclerView;
import com.squareup.picasso.Picasso;
import java.util.List;
public class MyAdapter extends
RecyclerView.Adapter<MyAdapter.MyViewHolder> {
Context ct;
List<String> name, description, image, video, category;
private final RecyclerViewInterface recyclerViewInterface;
public MyAdapter(Context ct, List<String> nameOfFilm, List<String>
descriptionOfFilm, List<String> imageUrl, List<String> videoUrl,
RecyclerViewInterface rci,List<String> category) {
name = nameOfFilm;
description = descriptionOfFilm;
image = imageUrl;
video = videoUrl;
this.ct = ct;
recyclerViewInterface = rci;
this.category = category;
}
#NonNull
#Override
public MyViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int
viewType) {
LayoutInflater inflater = LayoutInflater.from(ct);
View view = inflater.inflate(R.layout.my_row, parent, false);
return new MyViewHolder(view, recyclerViewInterface);
}
#Override
public void onBindViewHolder(#NonNull MyViewHolder holder, int
position) {
holder.nameFilm.setText(name.get(position));
holder.cardView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(ct, PlayerActivity.class);
}
});
Picasso.get().load(image.get(position)).into(holder.image2);
}
#Override
public int getItemCount() {
return image.size();
}
public static class MyViewHolder extends RecyclerView.ViewHolder {
TextView nameFilm;
ImageView image2;
CardView cardView;
public MyViewHolder(#NonNull View itemView, RecyclerViewInterface
recyclerViewInterface) {
super(itemView);
nameFilm = itemView.findViewById(R.id.nameTV);
image2 = itemView.findViewById(R.id.imageView2);
cardView = itemView.findViewById(R.id.cardView);
itemView.findViewById(R.id.sectionOFRecyclerView).setOnClickListener
(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (recyclerViewInterface != null) {
int pos = getAdapterPosition();
if (pos != RecyclerView.NO_POSITION) {
recyclerViewInterface.onItemClick(pos);
}
}
}
});
}
}
}
myAdapter isn't null

You are trying to create an instance of activity as global variable. That means the context has not been generated yet.
Basically you can just use requireContext() method of Fragment class. This will provide you the context.
As I have mentioned in comment, you need to update your onCreateView method as below:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_search, container, false);
}
Then, you need to initialize your view and other stuff on onViewCreated method. You can update that method like this:
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
recyclerView = view.findViewById(R.id.filmsList);
textView = view.findViewById(R.id.test);
rci = this;
nameOfFilm = new ArrayList<>();
youTubeUrl = new ArrayList<>();
photoUrl = new ArrayList<>();
descriptionToFilm = new ArrayList<>();
category = new ArrayList<>();
loadFilmsFromDB();
}
Notes
You don't have to send many string parameters to your adapter. It is better to create a Model class for that item, and send the list of that item. So, model classes will have all the data you need, and you can use them from that model. This will give you better coding style and will let you manage your data easier.
To communicate with your XML layout, you can use ViewBinding or DataBinding for that. This will also help you to use your view elements without creating variables for each of them.

Can I create method inside the fragment?

I am kind of new to android studio thing. I got some questions to ask. How do I add method locally in fragments and how can I show it in app? I am trying to show my data from existing database with REST API using Retrofit, to show it in Android fragment. I tried different tutorials from YouTube but I am not sure with it.
This is the code for RecyclerView Adapter:
package com.example.cyberview_android1;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import java.util.List;
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.RecyclerHolder> {
List<ProfileModel> models;
public RecyclerViewAdapter(List<ProfileModel> models) {
this.models = models;
}
#NonNull
#Override
public RecyclerHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.layout_row, viewGroup, false);
return new RecyclerHolder(view);
}
#Override
public void onBindViewHolder(#NonNull RecyclerHolder holder, int position) {
recyclerHolder.textView.setText(models.get(i).profile_cat);
}
#Override
public int getItemCount() {
return models.size();
}
public class RecyclerHolder extends RecyclerView.ViewHolder {
TextView textView;
public RecyclerHolder(#NonNull View itemView) {
super(itemView);
textView = itemView.findViewById(R.id.textTitle);
}
}
}
This is the code for Fragment:
package com.example.cyberview_android1;
import android.os.Bundle;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import java.util.List;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
public class ProfileFragment extends Fragment {
RecyclerView rvProfile;
public ProfileFragment() {
// Required empty public constructor
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
rvProfile = rvProfile.findViewById(R.id.rv_profile);
rvProfile.setLayoutManager(new LinearLayoutManager(ProfileFragment.this));
RetrofitInterface retrofitInterface = RetrofitInstance.getRetrofitInstance().create(RetrofitInterface.class);
Call<List<ProfileModel>> listCall = retrofitInterface.getAllProfile();
listCall.enqueue(new Callback<List<ProfileModel>>() {
#Override
public void onResponse(Call<List<ProfileModel>> call, Response<List<ProfileModel>> response) {
parseData(response.body());
}
#Override
public void onFailure(Call<List<ProfileModel>> call, Throwable t) {
}
});
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_profile, container, false);
}
private void parseData(List<ProfileModel> body) {
RecyclerViewAdapter recyclerViewAdapter = new RecyclerViewAdapter(body);
rvProfile.setAdapter(recyclerViewAdapter);
}
}package com.example.cyberview_android1;
import android.os.Bundle;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import java.util.List;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
public class ProfileFragment extends Fragment {
RecyclerView rvProfile;
public ProfileFragment() {
// Required empty public constructor
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
rvProfile = rvProfile.findViewById(R.id.rv_profile);
rvProfile.setLayoutManager(new LinearLayoutManager(ProfileFragment.this));
RetrofitInterface retrofitInterface = RetrofitInstance.getRetrofitInstance().create(RetrofitInterface.class);
Call<List<ProfileModel>> listCall = retrofitInterface.getAllProfile();
listCall.enqueue(new Callback<List<ProfileModel>>() {
#Override
public void onResponse(Call<List<ProfileModel>> call, Response<List<ProfileModel>> response) {
parseData(response.body());
}
#Override
public void onFailure(Call<List<ProfileModel>> call, Throwable t) {
}
});
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_profile, container, false);
}
private void parseData(List<ProfileModel> body) {
RecyclerViewAdapter recyclerViewAdapter = new RecyclerViewAdapter(body);
rvProfile.setAdapter(recyclerViewAdapter);
}
}
This is the retrofit instance code:
package com.example.cyberview_android1;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;
public class RetrofitInstance {
private static Retrofit retrofit;
private static final String BASE_URL = "http://localhost:5000/api/";
public static Retrofit getRetrofitInstance() {
if (retrofit == null) {
retrofit = new retrofit2.Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build();
}
return retrofit;
}
}
The interface:
package com.example.cyberview_android1;
import java.util.List;
import retrofit2.Call;
import retrofit2.http.GET;
public interface RetrofitInterface {
#GET("/employee/profile")
Call<List<ProfileModel>> getAllProfile();
}
And the model:
package com.example.cyberview_android1;
import com.google.gson.annotations.SerializedName;
public class ProfileModel {
#SerializedName("category")
String profile_cat;
#SerializedName("description")
String profile_desc;
#SerializedName("date")
String date;
public String getProfile_cat() {
return profile_cat;
}
public void setProfile_cat(String profile_cat) {
this.profile_cat = profile_cat;
}
public String getProfile_desc() {
return profile_desc;
}
public void setProfile_desc(String profile_desc) {
this.profile_desc = profile_desc;
}
public String getDate() {
return date;
}
public void setDate(String date) {
this.date = date;
}
}
Additionally, I am getting an error from the Holders and View groups. I followed the steps from the tutorial but I assure that I didnt miss anything from it.
I would really appreciate your help.

Change viewGroup with parent
And recyclerHolder with holder
And your error will go away

change :
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.layout_row, viewGroup, false);
to:
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.add_customer_customlist , parent , false);
and:
recyclerHolder.textView.setText(models.get(position).profile_cat);
to:
holder.textView.setText(models.get(position).profile_cat);
this would solve your problem but if you want to know what exactly does adapters do I have a brief explain for you:
adapters usually have 4 main parts :
1- onCreateViewHolder
2- A ViewHolder sub_class
3- onBindViewHolder
4- getItemCount
1-in onCreateViewHolder you will set your viewHolder xml view and then return a ViewHolder object.(this is where you create an instance of your itemView)
(you have two arguments here a ViewGroup and a viewType )
ViewGroup is the parent view of your itemView it means the parent of your xml layout file that you inflate in this method to create a view Object :
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.layout_row, viewGroup, false);
viewtype is for implementing multiple viewTypes in your recycler and is not necessary in your scenario so I just skip it.
2-in your viewHolder class you can get access to your itemView widgets.
3-in onBindViewHolder which will be called when you scroll or a dataset change by notifying the adapter, data will be set based on your model by its position
4-getItemCount will identify the size of your items in the adapter.(in your scenario it's models):
List<ProfileModel> models;

Mortuza is right. You can change your code like this:
#NonNull
#Override
public RecyclerHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_row, parent, false);
return new RecyclerHolder(view);
}
#Override
public void onBindViewHolder(#NonNull RecyclerHolder holder, int position) {
holder.textView.setText(models.get(position).profile_cat);
}
For second error you can use context. If you want to get context from fragment you can use getActivity() or requireActivity().
Remove this line:
rvProfile.setLayoutManager(new LinearLayoutManager(ProfileFragment.this));
And then add this line:
rvProfile.setLayoutManager(new LinearLayoutManager(getActivity()));

Cannot resolve method setText() in imageView

I'm trying to do a simple project with Recyclerview and Cardview in Android Studio following this tutorial.
But I'm getting an error in onBindViewHolder function line 32 saying it can't resolve the method setText() in imageView and I don't know why since mTitle is not an ImageView and it is a TextView:
package com.example.demoproject;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import java.util.ArrayList;
import android.content.Context;
public class MyAdapter extends RecyclerView.Adapter<MyHolder> {
Context c;
ArrayList<Model> models; // this array list creates a list of arrays which parameters define in my model class
public MyAdapter(Context c, ArrayList<Model> models) {
this.c = c;
this.models = models;
}
#NonNull
#Override
public MyHolder onCreateViewHolder(#NonNull ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.row,null); // this line inflate my row
return new MyHolder(view); // this will return my view to holder class
}
#Override
public void onBindViewHolder(#NonNull MyHolder myHolder, int i) {
myHolder.mTitle.setText(models.get(i).getTitle()); // here i is position
}
#Override
public int getItemCount() {
return 0;
}
}
MyHolder.java :
package com.example.demoproject.
import android.view.View;
import android.widget.ImageView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
public class MyHolder extends RecyclerView.ViewHolder {
ImageView mImaeView, mTitle;
public MyHolder(#NonNull View itemView) {
super(itemView);
this.mImaeView = itemView.findViewById(R.id.imageIv);
this.mTitle = itemView.findViewById(R.id.titleTv);
}
}

Your mTile is not a TextView it is a ImageView. Change it to this:
ImageView mImaeView;
TextView mTitle;
And make sure that itemView.findViewById(R.id.titleTv); returns TextView. Check in Your xml file (recycler view item) that You made it eveything well and titleTv is a TextView

because setText() method is set on textview not in imageView

RecyclerView that's supposed to diplay cardViews doesn't show anything

I have a recyclerView that must show a list of cards, but it doesn't!
There is an arrayList of recipes get passed to the adapter to display them as cardviews, everything in the debugging seems to be alright, but it doesnt display anything on the screen.
ViewHolder:
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;
import com.example.nd.ameer.bake.R;
public class RecipeViewHolder extends RecyclerView.ViewHolder {
public TextView titleTextView;
public ImageView coverImageView;
public RecipeViewHolder(View v) {
super(v);
titleTextView = (TextView) v.findViewById(R.id.titleTextView);
coverImageView = (ImageView) v.findViewById(R.id.recipeImageView);
}
}
Adapter:
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.bumptech.glide.Glide;
import com.example.nd.ameer.bake.R;
import com.example.nd.ameer.bake.models.Recipe;
import com.example.nd.ameer.bake.views.holders.RecipeViewHolder;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
public class RecipeAdapter extends
RecyclerView.Adapter<RecipeViewHolder> {
ArrayList<Recipe> recipes = new ArrayList<>();
Context context;
public RecipeAdapter(ArrayList<Recipe> recipes, Context context) {
this.recipes = recipes;
this.context = context;
}
#Override
public RecipeViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context).inflate(R.layout.recipe_item, parent, false);
return new RecipeViewHolder(view);
}
#Override
public void onBindViewHolder(RecipeViewHolder holder, int position) {
holder.coverImageView.setImageResource(R.color.colorPrimaryLight);
holder.titleTextView.setText(recipes.get(position).getName());
}
#Override
public int getItemCount() {
return recipes.size();
}
}
Fragment onCreateView:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
rootView = inflater.inflate(R.layout.fragment_recipe, container, false);
createRecipes();
recyclerView = (RecyclerView) rootView.findViewById(R.id.rv_recipe);
recyclerView.setHasFixedSize(true);
LinearLayoutManager layoutManager = new LinearLayoutManager(getContext());
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
if (recipes.size() > 0 & recyclerView != null) {
recyclerView.setLayoutManager(layoutManager);
recyclerView.setAdapter(new RecipeAdapter(recipes, getContext()));
}
return rootView;
}
The method createRecipes(); creates a list of recipes and then it get passed to the adapter.
as you can see, the recipes size is 4, so it's not the problem

I didn't know the cause of the problem till now, but I moved both the adapter and the view holder to the Recipes Fragment as inner classes, and this has fixed the problem.

proper way of creating method in your custom listview adapter

I created a simple android application with a ListView in it. I have my custom list adapter below:
package com.example.android.efaas;
import java.util.List;
import com.example.android.R;
import com.example.android.efaas.bean.ListItem;
import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class CustomListAdapter extends BaseAdapter {
LayoutInflater inflater = null;
Context ctx;
List<ListItem> data;
public CustomListAdapter(Activity activity, List<ListItem> data){
ctx = activity;
this.data = data;
inflater = ( LayoutInflater )ctx.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
#Override
public int getCount() {
return data.size();
}
#Override
public Object getItem(int pos) {
return pos;
}
#Override
public long getItemId(int pos) {
return pos;
}
#Override
public View getView(int pos, View view, ViewGroup vgroup) {
View rowView = inflater.inflate(R.layout.list_menu, null);
ImageView img = (ImageView) rowView.findViewById(R.id.list_menu_image);
TextView title = (TextView) rowView.findViewById(R.id.list_menu_title);
ListItem item = data.get(pos);
img.setImageResource(item.getId());
title.setText(item.getTitle());
return rowView;
}
public ListItem getListItem(int pos){
return data.get(pos);
}
}
I have a public method getListItem, I tried to call it during ListView onClick but somehow I cant seem to make it work. Here's the image of the problem:
How do I resolve this?

You should cast adapter.getAdapter() to CustomListAdapter class then

the compile time error is due of the fact that adapter is not your CustomListAdapter. What you can do is cast the return value of adapter.getAdapter() to CustomListAdapter. Conversely you should use what's already available to retrieve the object at position. Like getItemAtPosition(int)