I want to pass the code I have from an activity to some tabs and I get an error
NullPointerException: Attempt to invoke virtual method 'void android.support.v7.widget.RecyclerView.setLayoutManager(android.support.v7.widget.RecyclerView$LayoutManager)' on a null object reference
gives me a bug in the line that is inside the onCreateView
rv = vista.findViewById( R.id.recycler );
rv.setLayoutManager( new LinearLayoutManager( getActivity() ) );
Where can the shots go? What code can I show more so that you can help me? I do not know if this will work but I import the fragmnets with android.support.v4.app.Fragment;
xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/layout_VoteAct"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.lujan.confirmaciones.Views.FinalActivity">
<TextView
android:id="@+id/tvTitulo"
android:layout_width="wrap_content"
android:layout_height="40dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:maxLength="25"
android:text="@string/title"
android:textAlignment="center"
android:textColor="@color/ColorActionBarTitle"
android:textSize="28sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.501"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="@+id/tvDescripcion"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginEnd="8dp"
android:layout_marginStart="18dp"
android:layout_marginTop="8dp"
android:maxLength="70"
android:text="@string/description"
android:textAlignment="center"
android:textColor="@android:color/holo_blue_dark"
android:textSize="18sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/imageView2" />
<TextView
android:id="@+id/tvCodigo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="28dp"
android:layout_marginTop="4dp"
android:onClick="shareCode"
android:text="@string/code"
android:textAlignment="center"
android:textColor="#00bcd4"
app:layout_constraintBottom_toTopOf="@+id/tv_diasrestantes"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="@+id/tv_contador"
app:layout_constraintVertical_bias="0.0"
tools:ignore="OnClick" />
<ImageView
android:id="@+id/imageView2"
android:layout_width="330dp"
android:layout_height="102dp"
android:layout_marginTop="8dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/tvTitulo"
app:srcCompat="@android:drawable/sym_def_app_icon" />
<Button
android:id="@+id/btnYes"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="4dp"
android:layout_marginStart="36dp"
android:elevation="5dp"
android:onClick="yes"
android:text="@string/Yes"
android:textColor="@android:color/holo_green_dark"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
tools:ignore="OnClick" />
<Button
android:id="@+id/btnNo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="4dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:elevation="5dp"
android:onClick="no"
android:text="@string/No"
android:textColor="@android:color/holo_red_light"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.498"
app:layout_constraintStart_toStartOf="parent"
tools:ignore="OnClick" />
<Button
android:id="@+id/btnSoSo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="4dp"
android:layout_marginEnd="36dp"
android:elevation="5dp"
android:onClick="maybe"
android:text="@string/Maybe"
android:textColor="@android:color/holo_blue_bright"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
tools:ignore="OnClick" />
<TextView
android:id="@+id/tv_contador"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="8dp"
android:layout_marginTop="8dp"
android:text="@string/share_code"
android:textSize="14sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="@+id/recycler" />
<TextView
android:id="@+id/tv_diasrestantes"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="12dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:text="TextView"
android:textSize="16sp"
app:layout_constraintBottom_toTopOf="@+id/btnNo"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent" />
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler"
android:layout_width="0dp"
android:layout_height="301dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:layout_marginTop="12dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/tvDescripcion"
tools:ignore="MissingConstraints">
</android.support.v7.widget.RecyclerView>
<TextView
android:id="@+id/tv.calendar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="@string/add_to_calendary"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/recycler" />
<Button
android:id="@+id/bt.calendar"
android:layout_width="35dp"
android:layout_height="27dp"
android:layout_marginStart="30dp"
android:layout_marginTop="4dp"
android:background="@drawable/agendas"
android:onClick="calendario"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/tv.calendar"
tools:ignore="OnClick" />
<Button
android:id="@+id/btn_DeleteEvent"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="@color/ColorActionBarTitle"
android:onClick="deleteEvent"
android:text="@string/Delete_evento"
android:textColor="@android:color/background_dark"
android:visibility="gone"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
tools:ignore="OnClick" />
Fragment Code
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View vista = inflater.inflate( R.layout.tab3_fragment, container, false );
// loadLanguage();
// setContentView( R.layout.activity_final );
// return new FinalActivity(this);
// UI
layout = vista.findViewById( R.id.layout_VoteAct );
mTitle = vista.findViewById( R.id.tvTitulo );
mDescription = vista.findViewById( R.id.tvDescripcion );
mCode = vista.findViewById( R.id.tvCodigo );
mImage = vista.findViewById( R.id.imageView2 );
Si = vista.findViewById( R.id.btnYes );
No = vista.findViewById( R.id.btnNo );
Nose = vista.findViewById( R.id.btnSoSo );
Delete = vista.findViewById( R.id.btn_DeleteEvent );
compartir = vista.findViewById( R.id.tv_contador );
calendario = vista.findViewById( R.id.tv_calendar );
calendar = vista.findViewById( R.id.bt_calendar );
//prueba=findViewById( R.id.tv_prueba );
rv = vista.findViewById( R.id.recycler );
//cont=findViewById( R.id.tv_contador );
dias = vista.findViewById( R.id.tv_diasrestantes );
// Intent
code = getActivity().getIntent().getExtras().getString("code");
dataEventIntent = getActivity().getIntent().getExtras().getString("data");
guri = getActivity().getIntent().getExtras().getString("uri");
random = getActivity().getIntent().getExtras().getString("random");
// Intent intent = getIntent();
/*
code = intent.getStringExtra( "code" );
dataEventIntent=intent.getStringExtra( "data" );
guri=intent.getStringExtra( "uri" );
random=intent.getStringExtra( "random" );
*/
// Habilitar el modo OffLine de la BBDD
if (FirebaseApp.getApps( getActivity() ).isEmpty()) {
FirebaseApp.initializeApp( getActivity() );
FirebaseDatabase.getInstance().setPersistenceEnabled( true );
}
mDatabase = FirebaseDatabase.getInstance().getReference().child( "Events" ).child( code );
mDatabase.addValueEventListener( new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
Event event = dataSnapshot.getValue( Event.class );
mTitle.setText( event.getTitle() );
mDescription.setText( event.getDescription() );
// prueba.setText( event.getDateEvent() );
dataEvent=event.getDateEvent();
code=event.getCode();
url=event.getFoto();
mCode.setText(event.getCode());
ano=event.getAno();
mes=event.getMes();
dia=event.getDia();
countDate();//diferencia fechas
url();//foto evento
}
@Override
public void onCancelled(final DatabaseError databaseError) {
}
} );
user = FirebaseAuth.getInstance().getCurrentUser();
//RecyclerView
FirebaseDatabase database=FirebaseDatabase.getInstance();
usuarios=new ArrayList<>( );
rv.setLayoutManager( new LinearLayoutManager( getActivity() ) ); //FALLO RV RECIBE NULL
adapter=new Adapter( usuarios );
rv.setAdapter( adapter );
database.getReference("Events").child( code ).child( "Users" ).addValueEventListener( new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
usuarios.removeAll( usuarios );
for (DataSnapshot snapshot:dataSnapshot.getChildren()) {
User user=snapshot.getValue(User.class) ;
usuarios.add( user );
}
adapter.notifyDataSetChanged();
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
} );//cada vez que se cambien datos se refresca
countVote();
return vista;
}