When I try to run the app my recycler view unable to generate the output. It is unable to load data and there is no error the code.

Below is adapter class PlayerListAdapter.java

public class PlayerListAdapter extends RecyclerView.Adapter<PlayerListAdapter.FeaturedViewHolder> {

    ArrayList<plaerListHelperClass> featuredLocation;

    public PlayerListAdapter(ArrayList<plaerListHelperClass> featuredLocation) {
        this.featuredLocation = featuredLocation;
    }

    @NonNull
    @Override
    public FeaturedViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.playerlist,parent,false);
        FeaturedViewHolder featuredViewHolder= new FeaturedViewHolder(view);
        return featuredViewHolder;
    }

    @Override
    public void onBindViewHolder(@NonNull FeaturedViewHolder holder, int position) {

        plaerListHelperClass plaerListHelperClass = featuredLocation.get(position);
        String namep= plaerListHelperClass.getPlayerName();
        String mailp= plaerListHelperClass.getPlayerEmail();

        holder.name.setText(namep);
        holder.mail.setText(mailp);

    }

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

    public static class FeaturedViewHolder extends RecyclerView.ViewHolder{

        TextView name,mail;

        public FeaturedViewHolder(@NonNull View itemView) {
            super(itemView);

            name=itemView.findViewById(R.id.playerName);
            mail=itemView.findViewById(R.id.pmail);
        }
    }

mainactivity.java This is main activity of my code

public class MainActivity extends AppCompatActivity {
    RecyclerView featuredRecycler;
    RecyclerView.Adapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        featuredRecycler=findViewById(R.id.playerListRecyclerView);

        featuredRecycler();
    }

    private void featuredRecycler() {
        featuredRecycler.setHasFixedSize(true);

        ArrayList<plaerListHelperClass> featuredLocation = new ArrayList<>();

        featuredLocation.add(new plaerListHelperClass("Shubham","[email protected]"));
        featuredLocation.add(new plaerListHelperClass("Shubham","[email protected]"));
        featuredLocation.add(new plaerListHelperClass("Shubham","[email protected]"));
        featuredLocation.add(new plaerListHelperClass("Shubham","[email protected]"));

        adapter=new PlayerListAdapter(featuredLocation);

        featuredRecycler.setAdapter(adapter);

    }

Build this helper class to contains the element that is to be send to the recycler view layout

plaerListHelperClass.java

public class plaerListHelperClass {
    String playerName;
    String playerEmail;

    public plaerListHelperClass(String playerName, String playerEmail) {
        this.playerName = playerName;
        this.playerEmail = playerEmail;
    }

    public String getPlayerName() {
        return playerName;
    }

    public String getPlayerEmail() {
        return playerEmail;
    }
}

playerlist.xml

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white">
    <TextView
        android:id="@ id/playerName"
        android:layout_height="wrap_content"
        android:textColor="#897668"
        android:layout_weight="1.50"
        android:layout_width="match_parent"
        android:layout_marginTop="10dp"
        android:layout_marginLeft="0dp"/>
    <TextView
        android:id="@ id/pmail"
        android:layout_height="wrap_content"
        android:textColor="#897668"
        android:layout_below="@ id/name"
        android:layout_width="match_parent"
        android:layout_weight="1"
        android:layout_marginTop="10dp"
        android:layout_centerHorizontal="true"/>



</LinearLayout>

activity_main.xml

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:background="@color/white">

    <androidx.recyclerview.widget.RecyclerView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@ id/playerListRecyclerView"
        tools:ignore="MissingConstraints" />

</androidx.constraintlayout.widget.ConstraintLayout>

CodePudding user response：

Welcome to the Stack Overflow,

your implementation is correct but I guess you forgot to add the Layout Manager for RecyclerView.

so you can do this by adding it in xml or in your java class as :

activity_main.xml

    <?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:background="@color/white">

<!--    for Linear layout...-->
    <androidx.recyclerview.widget.RecyclerView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@ id/playerListRecyclerView"
        tools:listitem="@layout/playerlist"
        tools:itemCount="7"
        app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
        tools:ignore="MissingConstraints" />

</androidx.constraintlayout.widget.ConstraintLayout>

Or,

you can add it in your java class as

 private void featuredRecycler() {
            featuredRecycler.setHasFixedSize(true);
    
            ArrayList<plaerListHelperClass> featuredLocation = new ArrayList<>();
    
            featuredLocation.add(new plaerListHelperClass("Shubham","[email protected]"));
            featuredLocation.add(new plaerListHelperClass("Shubham","[email protected]"));
            featuredLocation.add(new plaerListHelperClass("Shubham","[email protected]"));
            featuredLocation.add(new plaerListHelperClass("Shubham","[email protected]"));
    
            adapter=new PlayerListAdapter(featuredLocation);
    
            featuredRecycler.setAdapter(adapter);
            featuredRecycler.setLayoutManager(new LinearLayoutManager(this@MainActivity))

        }

for more reference you can refer https://www.javatpoint.com/android-recyclerview-list-example