Develop Reference

How to retrieve data from Firebase in android RealTimeDatabase to update on the basis of regid

I want to retrieve data from my Realtime Database server so that I can update values based on the reg-id (stored this as a child string, not as Auth) I have saved for the user.
I have done this till now
private void updateDatatoFirebase(String regid, String doctor_name, String city,String speciality) {
Map<String, Object> update=new HashMap<>();
update.put("doctor",doctor_name);
update.put("city",city);
update.put("speciality",speciality);
DatabaseReference dbref=FirebaseDatabase.getInstance().getReference();
dbref.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot snapshot) {
for (DataSnapshot ds : snapshot.getChildren()){
key = snapshot.getKey();
if(checkid.equalsIgnoreCase(regid))
{
dbref.updateChildren(update);
Toast.makeText(need_help.this, "Data in Database updated", Toast.LENGTH_SHORT).show();
}
else
Toast.makeText(need_help.this, "No such id found", Toast.LENGTH_SHORT).show();
}
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
Toast.makeText(need_help.this, "Fail to add data " + error, Toast.LENGTH_SHORT).show();
}
});
}
to update but it won't update
and I have saved data like this
private void addDatatoFirebase(String regid, String doctor_name, String city,String speciality) {
root=firebaseDatabase.getReference().child("RegId").child(regid);
HashMap<String, String> usermap=new HashMap<>();
usermap.put("doctor",doctor_name);
usermap.put("city",city);
usermap.put("speciality",speciality);
root.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot snapshot) {
root.push().setValue(usermap);
Toast.makeText(need_help.this, "Data in Database updated", Toast.LENGTH_SHORT).show();
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
Toast.makeText(need_help.this, "Fail to add data " + error, Toast.LENGTH_SHORT).show();
}
});

To be able to update all children under a particular node, for instance, 1234, you have to pass to the following method, 1234 as the first argument:
private void updateDatatoFirebase(String regid, String doctor_name, String city,String speciality) {
Map<String, Object> update=new HashMap<>();
update.put("doctor",doctor_name);
update.put("city",city);
update.put("speciality",speciality);
DatabaseReference dbref=FirebaseDatabase.getInstance().getReference();
dbref.child("RegId").child(regid).addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot snapshot) {
for (DataSnapshot ds : snapshot.getChildren()){
ds.getRef().updateChildren(update).addOnCompleteListener(new OnCompleteListener<Void>() {
#Override
public void onComplete(#NonNull Task<Void> task) {
if (task.isSuccessful()) {
Toast.makeText(need_help.this, "Data in Database updated", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(need_help.this, "Failed with an error: " + task.getException().getMessage(), Toast.LENGTH_SHORT).show();
}
}
});
}
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
Toast.makeText(need_help.this, "Fail to add data " + error, Toast.LENGTH_SHORT).show();
}
});
}
Things to notice:
I have added two extra calls .child("RegId") and .child(regid) call right after the root reference.
I have used the ds to call getRef() and then .updateChildren(update).
I have attached a listener to see if something goes wrong when updating the children under 1234.

Check if the user in the database firebase exists

I would like to check if the user in the database exists. with this line of codes, it says that it exists and also that it does not exist. I want to make the code read-only if the name exists in one of the registers
enter image description here
Firebase database
private void Criar_Conta() {
databaseReference_users.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
if (dataSnapshot.exists()) {
for (DataSnapshot snapshot : dataSnapshot.getChildren()) {
if (snapshot.child("usuario").getValue().equals(Usuario.getText().toString()) && snapshot.getKey().equals(Usuario.getText().toString()) && snapshot.getKey().equals(snapshot.child("usuario").getValue())) {
Toast.makeText(Sign_Up.this, "Usuário Existente", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(Sign_Up.this, "Gravar ...", Toast.LENGTH_SHORT).show();
//Gravar_Dados();
}
}
} else {
Gravar_Dados();
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
Toast.makeText(Sign_Up.this, databaseError.getMessage(), Toast.LENGTH_LONG).show();
Swipe.setRefreshing(true);
}
});

This is my code sample I hope this helps you
loginBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
final String phoneTxt = phone.getText().toString();
final String passwordTxt = password.getText().toString();
if (phoneTxt.isEmpty() || passwordTxt.isEmpty()){
Toast.makeText(Login.this, "Please Enter Your Phone Number Or Password", Toast.LENGTH_SHORT).show();
}else {
databaseReference.child("users").addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot snapshot) {
if (snapshot.hasChild(phoneTxt)){
final String getpassword = snapshot.child(phoneTxt).child("password").getValue(String.class);
if (getpassword.equals(passwordTxt)){
Toast.makeText(Login.this, "Successfully login! ", Toast.LENGTH_SHORT).show();
startActivity(new Intent(Login.this,HomeScreen.class));
finish();
}
else{
Toast.makeText(Login.this, "Wrong Password", Toast.LENGTH_SHORT).show();
}
}
else {
Toast.makeText(Login.this, "Wrong Phone Number!", Toast.LENGTH_SHORT).show();
}
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
}
});
}
}
});

To be able to check if a specific user exists in the database, you should only perform a get(), and not attach a ValueEventListener. Assuming that the users are direct children of your Firebase Realtime Database root, in code, will be as simple as:
DatabaseReference db = FirebaseDatabase.getInstance().getReference();
String usuario = Usuario.getText().toString();
DatabaseReference usuarioRef = db.child(usuario);
usuarioRef.get().addOnCompleteListener(new OnCompleteListener<DataSnapshot>() {
#Override
public void onComplete(#NonNull Task<DataSnapshot> task) {
if (task.isSuccessful()) {
DataSnapshot snapshot = task.getResult();
if(snapshot.exists()) {
Log.d("TAG", "User exists.");
} else {
Log.d("TAG", "User doesn't exist.");
}
} else {
Log.d("TAG", task.getException().getMessage()); //Never ignore potential errors!
}
}
});

firebase realtime database push infinite loop error

I'm using firebase authentication with email and password.
So I want to save user data in realtime database .
But when i push the data to database, infinite loop was executing.
I don't know why..
I want to save data like this form and continue saving.
But when I starting, infinite loop is starting
private void createUser(String email, String password,String name, String phone, String
nickname) {
firebaseAuth.createUserWithEmailAndPassword(email, password)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
if (task.isSuccessful()) { //Join Success
Toast.makeText(JoinActivity.this, "Join Success", Toast.LENGTH_SHORT).show();
mDatabase.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
if(firebaseAuth.getCurrentUser()!=null) {
String email=editTextEmail.getText().toString().trim();
FirebaseUser user=firebaseAuth.getCurrentUser();
String uid=user.getUid();
if(dataSnapshot.child("USER").child("user_info").child(uid).exists()){
Toast.makeText(JoinActivity.this,"already exist",Toast.LENGTH_SHORT).show();
}else{
User user_info = new User(uid, editTextId.getText().toString(), editTextEmail.getText().toString(), editTextPassword.getText().toString(),
editTextname.getText().toString(), editTextNickname.getText().toString(), editTextPhone.getText().toString());
//delete all data
mDatabase.setValue(null);
String key = mDatabase.child("USER").push().getKey();
// mDatabase.child("USER").child("user_info").child(key).setValue(user_info);
Toast.makeText(JoinActivity.this, "save the data", Toast.LENGTH_SHORT).show();
}
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
Intent intent = new Intent(JoinActivity.this, MainActivity.class);
startActivity(intent);
} else { //already exists
Toast.makeText(JoinActivity.this, "already exists", Toast.LENGTH_SHORT).show();
return;
}
}
});
}
}

Instead of :
mDatabase.addValueEventListener(new ValueEventListener() {
Use the following:
mDatabase.addListenerForSingleValueEvent(new ValueEventListener() {
This way you will retrieve data only once.

I am trying to use two firebase authentications (client, customer), I need to use firebase auth with database query

private void userSign() {
mAuth.signInWithEmailAndPassword(email, password).addOnCompleteListener(new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
if (!task.isSuccessful()) {
String message = Objects.requireNonNull(task.getException()).getMessage();
Toast.makeText(Start.this, "Error occured: " + message, Toast.LENGTH_SHORT).show();
dialog.dismiss();
}
else
{
Query DatabaseQuery = databaseReference.child("Users").child("Customer").orderByChild("email").equalTo(CLemail.getText().toString().trim());
DatabaseQuery.addListenerForSingleValueEvent(new ValueEventListener()
{
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot)
{
if (dataSnapshot.exists())
{
for (DataSnapshot user : dataSnapshot.getChildren())
{
User usersBean = user.getValue(User.class);
if (!usersBean.password.equals(CLpassword.getText().toString().trim()))
{
CLpassword.setError("Password is Wrong!");
CLpassword.requestFocus();
}
else
{
Intent intent = new Intent(Start.this, Home.class);
startActivity(intent);
dialog.setMessage("Loging please wait");
dialog.setIndeterminate(true);
dialog.show();
}
}
}
else {
Toast.makeText(Start.this, "User not found", Toast.LENGTH_LONG).show();
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError)
{
Toast.makeText(Start.this, "Email not found", Toast.LENGTH_LONG).show();
}
});
dialog.dismiss();
Intent intent = new Intent(Start.this, Home.class);
startActivity(intent);
}
}
});
}

How to get the URL of multiple images in Firebase

I'm storing multiple images at once in Firebase Storage and I need to get the URL of each one of them in the Firebase databse.
Here's the code:
private void SaveVersus() {
comment = Comment.getText().toString();
if (imageUri==null||imageUri2==null){
Toast.makeText(this, "...Select a Image...", Toast.LENGTH_SHORT).show();
}
else if(imageUri!=null&&imageUri2!=null&&imageUri3==null&&imageUri4==null) {
//Save2ImagesFirebase();
List<Uri> uri = Arrays.asList(imageUri,imageUri2);
storeMultipleImages(uri);
}
else if(imageUri!=null&&imageUri2!=null&&imageUri3!=null&&imageUri4==null){
//Save3ImagesFirebase();
List<Uri> uri2 = Arrays.asList(imageUri,imageUri2,imageUri3);
storeMultipleImages(uri2);
}
else if(imageUri!=null&&imageUri2!=null&&imageUri3!=null&&imageUri4!=null){
//Save4ImagesFirebase();
List<Uri> uri3 = Arrays.asList(imageUri,imageUri2,imageUri3,imageUri4);
storeMultipleImages(uri3);
}
}
public void storeImage(Uri imageUri) {
StorageReference filepath = mStorage.child("Versus Images").child(imageUri.getLastPathSegment());
filepath.putFile(imageUri).addOnCompleteListener(new OnCompleteListener<UploadTask.TaskSnapshot>() {
#Override
public void onComplete(#NonNull Task<UploadTask.TaskSnapshot> task) {
if (task.isSuccessful()){
downloadURL = task.getResult().getUploadSessionUri().toString();
Toast.makeText(ImageVersus.this, "Versus Published", Toast.LENGTH_SHORT).show();
GetInDB();
}
else{
Toast.makeText(ImageVersus.this, "..Error..", Toast.LENGTH_SHORT).show();
}
}
});
}
private void GetInDB() {
mDatabase.child(current_userID).addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
if(dataSnapshot.exists()){
String username = dataSnapshot.child("Username").getValue().toString();
HashMap InfoMap = new HashMap<>();
InfoMap.put("username",username);
InfoMap.put("imageUrl",downloadURL);
versusDBRef.child(current_userID).updateChildren(InfoMap);
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
}
public void storeMultipleImages(List<Uri> imageUris) {
for (Uri uri : imageUris) {
storeImage(uri);
}
}
The problem is that, in the hashmap, I can only put the URL of one image and I need to get multiple URLs depending on what the amount of pictures the user select, if they chose two, then in the hashmap must be two URL's and so on.