Here i am trying to retrieve data stored in firebase into ha header of my navigation drawer but data snapshot is not retrieving the values from firebase. here is my code
public class MainActivitylite extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener{
private DrawerLayout drawer_layout;
private Toolbar toolbar;
private NavigationView navigation_view;
// private CircleImageView nav_profile_image;
private TextView nav_fullname, nav_email, nav_contact, nav_type;
private DatabaseReference userRef;
private DatabaseReference reference;
private RecyclerView recyclerview;
private ProgressBar progressbar;
private List<User> userList;
private UserAdapter userAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main3);
toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setTitle("My Hospital");
drawer_layout = findViewById(R.id.drawer_layout);
navigation_view = findViewById(R.id.navigation_view);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(MainActivitylite.this, drawer_layout,
toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_closed);
drawer_layout.addDrawerListener(toggle);
toggle.syncState();
navigation_view.setNavigationItemSelectedListener(this);
progressbar = findViewById(R.id.progressbar);
recyclerview = findViewById(R.id.recyclerview);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
layoutManager.setReverseLayout(true);
layoutManager.setStackFromEnd(true);
recyclerview.setLayoutManager(layoutManager);
userList = new ArrayList<>();
userAdapter = new UserAdapter(MainActivitylite.this, userList);
recyclerview.setAdapter(userAdapter);
reference = FirebaseDatabase.getInstance().getReference()
.child("users").child(FirebaseAuth.getInstance().getCurrentUser().getUid());
reference.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
String type = snapshot.child("type").getValue().toString();
if (type.equals("patient")){
readRecipients();
}else {
readPatient();
}
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
}
});
// nav_profile_image = nav_view.getHeaderView(0).findViewById(R.id.nav_user_image);
nav_fullname = navigation_view.getHeaderView(0).findViewById(R.id.nav_fullname);
nav_email = navigation_view.getHeaderView(0).findViewById(R.id.nav_email);
nav_contact = navigation_view.getHeaderView(0).findViewById(R.id.nav_contact);
nav_type = navigation_view.getHeaderView(0).findViewById(R.id.nav_type);
userRef = FirebaseDatabase.getInstance().getReference().child("users").child(
FirebaseAuth.getInstance().getCurrentUser().getUid()
);
userRef.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
if (snapshot.exists()){
String name = snapshot.child("name").getValue().toString();
nav_fullname.setText(name);
String email = snapshot.child("email").getValue().toString();
nav_email.setText(email);
String phonenumber = snapshot.child("phonenumber").getValue().toString();
nav_contact.setText(phonenumber);
String type = snapshot.child("type").getValue().toString();
nav_type.setText(type);
}
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
}
});
}
private void readPatient() {
DatabaseReference reference = FirebaseDatabase.getInstance().getReference()
.child("users");
Query query = reference.orderByChild("type").equalTo("patient");
query.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
userList.clear();
for (DataSnapshot dataSnapshot : snapshot.getChildren()){
User user = dataSnapshot.getValue(User.class);
userList.add(user);
}
userAdapter.notifyDataSetChanged();
progressbar.setVisibility(View.GONE);
if (userList.isEmpty()){
Toast.makeText(MainActivitylite.this, "No recipients", Toast.LENGTH_SHORT).show();
progressbar.setVisibility(View.GONE);
}
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
}
});
}
private void readRecipients() {
DatabaseReference reference = FirebaseDatabase.getInstance().getReference()
.child("users");
Query query = reference.orderByChild("type").equalTo("Doctor");
query.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
userList.clear();
for (DataSnapshot dataSnapshot : snapshot.getChildren()){
User user = dataSnapshot.getValue(User.class);
userList.add(user);
}
userAdapter.notifyDataSetChanged();
progressbar.setVisibility(View.GONE);
if (userList.isEmpty()){
Toast.makeText(MainActivitylite.this, "No recipients", Toast.LENGTH_SHORT).show();
progressbar.setVisibility(View.GONE);
}
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
System.out.println("The read failed: " + error.getCode());
}
});
}
All the values which I am trying to retrieve at string name,type,contact are not getting retrieved.Its not even getting inside the if loop if(snapshot.exists())) and the code above where type is to be retrieved is showing null pointer error.
