I'm trying to popular a RecyclerView with the FirebaseRecyclerAdapter. When the onBindViewHolder method is called to populate the layout through the ViewHolder class, the error is triggered:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: br.com.coop.ascenderideias.maissaude, PID: 19982
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
at br.com.coop.ascenderideias.maissaude.viewHolder.MyViewHolder.bind(MyViewHolder.java:19)
at br.com.coop.ascenderideias.maissaude.MainActivity$3.onBindViewHolder(MainActivity.java:93)
at br.com.coop.ascenderideias.maissaude.MainActivity$3.onBindViewHolder(MainActivity.java:84)
at com.firebase.ui.database.FirebaseRecyclerAdapter.onBindViewHolder(FirebaseRecyclerAdapter.java:122)
at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:6673)
at android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:6714)
at android.support.v7.widget.RecyclerView$Recycler.tryBindViewHolderByDeadline(RecyclerView.java:5647)
at android.support.v7.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:5913)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5752)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5748)
at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2232)
at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1559)
at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1519)
at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:614)
at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3812)
at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:3529)
at android.support.v7.widget.RecyclerView.consumePendingUpdateOperations(RecyclerView.java:1767)
at android.support.v7.widget.RecyclerView$1.run(RecyclerView.java:356)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858)
at android.view.Choreographer.doCallbacks(Choreographer.java:670)
at android.view.Choreographer.doFrame(Choreographer.java:603)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
at android.os.Handler.handleCallback(Handler.java:746)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5443)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
I'm not sure how to solve it. Previously I loaded the data from the firebase to an arraylist, but even then the objects are only listed after the second boot, after installing the application. From what I understand, the data is not being returned, how do I solve it?
Model:
public class Instituicao {
private String nome;
public Instituicao() {
}
public Instituicao(String nome) {
this.nome = nome;
}
...
public String getNome() {
return nome;
}
public void setNome(String nome) {
this.nome = nome;
}
@Exclude
public Map<String, Object> toMap() {
HashMap<String, Object> result = new HashMap<>();
result.put("Nome", getNome());
return result;
}
@Override
public String toString() {
return "Instituicao{" + "Nome='" + nome +'}';
}
}
ViewHolder
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.TextView;
import br.com.coop.ascenderideias.maissaude.Dominio.Instituicao;
import br.com.coop.ascenderideias.maissaude.R;
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView titulo;
public MyViewHolder(View itemView) {
super(itemView);
titulo = (TextView) itemView.findViewById(R.id.edt_label_nome);
}
public void bind(Instituicao model) {
titulo.setText(model.getNome().toString());
}
}
Activity
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.design.widget.FloatingActionButton;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.firebase.ui.database.FirebaseRecyclerAdapter;
import com.firebase.ui.database.FirebaseRecyclerOptions;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.Query;
import br.com.coop.ascenderideias.maissaude.Dominio.Instituicao;
import br.com.coop.ascenderideias.maissaude.viewHolder.MyViewHolder;
import butterknife.BindView;
import butterknife.ButterKnife;
public class MainActivity extends AppCompatActivity {
private static final String TAG = "MainActivity";
protected static Query instQuery =
FirebaseDatabase.getInstance().getReference().child("INSTITUICAO").limitToLast(50);
@BindView(R.id.lista_recyclerview)
RecyclerView mRecyclerView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.bind(this);
mRecyclerView = (RecyclerView) findViewById(R.id.lista_recyclerview);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
FloatingActionButton fab = findViewById(R.id.floatingActionButton);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
startActivity(new Intent(MainActivity.this,CadastroInstituicaoActivity.class));
}
});
}
@Override
protected void onStart() {
super.onStart();
attachRecyclerViewAdapter();
}
@Override
protected void onStop() {
super.onStop();
}
private void attachRecyclerViewAdapter() {
final RecyclerView.Adapter adapter = newAdapter();
// Scroll to bottom on new messages
adapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
@Override
public void onItemRangeInserted(int positionStart, int itemCount) {
mRecyclerView.smoothScrollToPosition(adapter.getItemCount());
}
});
mRecyclerView.setAdapter(adapter);
}
protected RecyclerView.Adapter newAdapter() {
FirebaseRecyclerOptions<Instituicao> options =
new FirebaseRecyclerOptions.Builder<Instituicao>()
.setQuery(instQuery, Instituicao.class)
.setLifecycleOwner(this)
.build();
return new FirebaseRecyclerAdapter<Instituicao, MyViewHolder>(options) {
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new MyViewHolder(LayoutInflater.from(parent.getContext())
.inflate(R.layout.item_lista_instituicao, parent, false));
}
@Override
protected void onBindViewHolder(@NonNull MyViewHolder holder, int position, @NonNull Instituicao model) {
holder.bind(model);
}
@Override
public void onDataChanged() {
// If there are no chat messages, show a view that invites the user to add a message.
}
};
}
}