IntroductionAdapter.java

public class IntroductionAdapter extends RecyclerView.Adapter<IntroductionAdapter.MyViewHolder> {


    private List<Introduction> introductionList;
    Context context;     // changes

    public IntroductionAdapter(Context context, List<Introduction> introductionList) {   // changes
        this.context = context;    // changes(here you can see context)
        this.introductionList = introductionList;
    }

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemView = LayoutInflater.from(context)
                .inflate(R.layout.introduction_list, parent, false);  // change

        return new MyViewHolder(itemView);
    }

    @Override
    public void onBindViewHolder(@NonNull final MyViewHolder holder, int position) {
        final Introduction introduction = introductionList.get(position);


        if (introduction.getImage() != null) {

            Glide.with(holder.imageView).load(introduction.getImage()).into(holder.imageView);
        }


        holder.introduction.setText(introduction.getIntroduction());

    }

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

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

    public class MyViewHolder extends RecyclerView.ViewHolder {
        public TextView introduction, about;
        public CircularImageView imageView;

        public MyViewHolder(View view) {
            super(view);


            introduction = (TextView) view.findViewById(R.id.introduction);
            about = (TextView) view.findViewById(R.id.about);
            imageView = (CircularImageView) view.findViewById(R.id.circularImageView);

        }
    }
}

IntroductionItem.java

public class IntroductionItem extends AppCompatActivity {
    public RealmList<Introduction> introductionList;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.introduction);

        RecyclerView recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
        //TODO move this initialization to App extends Application

        RealmConfiguration realmConfiguration = new RealmConfiguration.Builder().build();

        final Realm realm = Realm.getInstance(realmConfiguration);

        KitabInterface kitabInterface = ApiClient.getApiService();
        Call<KitabSawti> call = kitabInterface.getIntroduction();
        call.enqueue(new Callback<KitabSawti>() {
            @Override
            public void onResponse(Call<KitabSawti> call, Response<KitabSawti> response) {

                introductionList = response.body().getIntroduction();
                recyclerView.setAdapter(new IntroductionAdapter(IntroductionItem.this, introductionList));

                realm.beginTransaction();


                    Introduction introduction = realm.createObject(Introduction.class);
                    introduction.setImage(introductionList.get(0).getImage());
                    introduction.setIntroduction(introductionList.get(0).getIntroduction());

                realm.commitTransaction();


            }

            @Override
            public void onFailure(Call<KitabSawti> call, Throwable t) {

                List<Introduction> list = realm.where(Introduction.class).findAll();
                if (list != null) {

                    recyclerView.setAdapter(new IntroductionAdapter(IntroductionItem.this, list));

                }

            }

        });


    }
}

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