In my app, users can create a post, and update their profile picture, but when they do, their profile picture of their created posts does not change. I thought I solved it with the following code, but it was not.
Does anyone know how to fix it?
In BD I have the following structure as seen in the image, and in each post id the data of the user id are saved, what I want to do is that regardless of the post id in all children where the userId node is the same To the current user the userPhoto node is updated, I thought that with the image code it would be enough but what it does is create a new child node of Posts but it is not what I am looking for how could I solve what they think.
final DatabaseReference sd = FirebaseDatabase.getInstance().getReference("Posts");
Query query = sd.orderByChild("userPhoto").equalTo(currentUsers.getPhotoUrl().toString());
query.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
HashMap<String, Object> maps = new HashMap<>();
maps.put("userPhoto", ""+mUri);
sd.updateChildren(maps);
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
If you want to update the userPhoto under the id, then you can do the following:
final DatabaseReference sd = FirebaseDatabase.getInstance().getReference("Posts");
Query query = sd.orderByChild("userPhoto").equalTo(currentUsers.getPhotoUrl().toString());
query.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()){
String key = ds.getKey();
HashMap<String, Object> maps = new HashMap<>();
maps.put("userPhoto", ""+mUri);
sd.child(key).updateChildren(maps);
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
Since you are doing a query, then all you need to do is iterate and then you will retrieve the correct random id, and then use it in the path child(key)
Related
I'm new to Firebase I wanted to know is there a way to only get the value of first child and insert it into my spinner in android. Ex:
Just like the image shown I wanted to retrieve only the name "slot x" instead of getting all the values of it. Is it possible to do so?
Sure thing, you can order and limit the number of child nodes retrieved with something like this:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference myRef = rootRef.child("path to your parent node");
Query query = myRef.orderByKey().limiToFirst(1);
query.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot childSnapshot: dataSnapshot.getChildren()) {
String key = childSnapshot.getKey(); // "slot 1"
String status = childSnapshot.child("status").getValue(String.class); // "occupied"
...
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
throw databaseError.toException();
}
});
I have developed an admin side application from where I will be adding the email id, pin, city and country data to the firebase realtime database. Then I will be providing the email and pin to the customer. So my simple target is that when the customer logins, the data of city and country should be displayed on his application. To do this I have to search the database for that particular customer's node which can be done through the email id which he puts during login.
I tried my best but everytime null is returned. Please have a look at my code and help me out.
void searchQuery(String email){
DatabaseReference mFirebaseDatabaseReference = FirebaseDatabase.getInstance().getReference();
Query query = mFirebaseDatabaseReference.child("arvi-admin").orderByChild("mailId").equalTo(email);
query.addValueEventListener(valueEventListener);
}
ValueEventListener valueEventListener = new ValueEventListener()
{
#Override
public void onDataChange(DataSnapshot dataSnapshot)
{
try {
DataModel obj = dataSnapshot.getValue(DataModel.class);
logData(""+obj.getCity()); //the values are null
}catch (Exception e){
Log.d("##","Error");
e.printStackTrace();
}
}
#Override
public void onCancelled(DatabaseError databaseError){
}
};
Firebase Database Image
To solve this, please change the following line of code:
Query query = mFirebaseDatabaseReference.child("arvi-admin").orderByChild("mailId").equalTo(email);
to
Query query = mFirebaseDatabaseReference.orderByChild("mailId").equalTo(email);
As you can see, I have removed the call to .child("arvi-admin") because the root is not a child and should not be added in your reference.
Edit:
Query query = mFirebaseDatabaseReference.orderByChild("mailId").equalTo(email);
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
DataModel obj = ds.getValue(DataModel.class);
Log.d(TAG, obj.getCity());
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
Log.d(TAG, databaseError.getMessage()); //Don't ignore errors!
}
};
query.addListenerForSingleValueEvent(valueEventListener);
I want to retrive division and rno from for all key in array and compare those values in array with two other strings. how to do that?
You can get all children. try below code:
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference reference = database.getReference();
reference.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot ds: dataSnapshot.getChildren()) {
String rno = ds.child("rno").getValue().toString();
String div = ds.child("division").getValue().toString();
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
I don't understand your question. But you can play on those who fulfill the requirements of the child and fulfill the conditions.
DatabaseReference roomRef = dbRef.child("Everybody Room List Messages");
ValueEventListener roomEventListener = new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
for (DataSnapshot dsKey : dataSnapshot.getChildren()) {
for (DataSnapshot dsNick : dsKey.getChildren()) {
if (dsNick.child("nick").getValue().toString().equals(Nick)) {
dsNick.child("image").getRef().setValue("");
}
}
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
};
roomRef.addListenerForSingleValueEvent(roomEventListener);
UPDATE
So, if I understand, you need this code:
FirebaseDatabase database = FirebaseDatabase.getInstance();
database.getReference().addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot item: dataSnapshot.getChildren()) {
String snapDiv = item.child("division").getValue().toString();
String snapRno = item.child("rno").getValue().toString();
if(snapDiv.equals(divi) && snapRno.equals(roll)){
//Here you can do everythings you need because division and rno value are those you are searching.
}
}
}
});
I can't understand completly your question.
You need to retrieve for each child his division and rno value. After that you need to compare them with other variables. But in the session these variables are 2 and fixed or you need to compare with a list of pairs?
After that, assuming that the above question will be clarify, if strings are matches, you need to update the value of sub1, sub2,...,sub5 fields?
Please, give us more informations to understand your situation and give you more support.
I am trying to display all child "name" located in my database tree. My Database tree I used the Map to do so:
GenericTypeIndicator<Map<String, Object>> m = new GenericTypeIndicator<Map<String, Object>>() {};
Map<String, Object> map = snapshot.getValue(m);
String username = (String) map.get("name");
displayName.setText(username);// Display the name
I am displaying all the data into a recyclerView. But for some reasons instead of getting all names(Eva, smith, princess), I am only one which is the lastest one created "princess" being displayed 3 times in my recyclerView layout(princess, princess, princess). Anyone has any idea what I am doing wrong?
Assuming that you have a node named users in which you have all those uid's, to get all those name, please use the code below. Is the easiest way to achieve this.
DatabaseReference yourRef = FirebaseDatabase.getInstance().getReference().child("users");
ValueEventListener eventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String userId = (String) dataSnapshot.getKey();
DatabaseReference userIdRef = FirebaseDatabase.getInstance().getReference().child("users").child(userId);
ValueEventListener eventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String name = (String) dataSnapshot.child("name").getValue();
Log.d("TAG", name);
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
userIdRef.addListenerForSingleValueEvent(eventListener);
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
yourRef.addListenerForSingleValueEvent(eventListener);
Hope it helps.
I try to get data from the database.
Code:
mDatabaseUsers = FirebaseDatabase.getInstance().getReference().child("User")mDatabaseUsers.orderByChild("name").startAt("m");
mDatabaseUsers.keepSynced(true); mDatabaseUsers.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
Map<String, String> map = dataSnapshot.getValue(Map.class);
String name = map.get("name");
Toast.makeText(AddFriendActivity.this,nick.toString(),Toast.LENGTH_SHORT).show();
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
I want to get all users with the letter m!
How does is work?
Thank you!
When you execute a query against the Firebase Database, there will potentially be multiple results. So the snapshot contains a list of those results. Even if there is only a single result, the snapshot will contain a list of one result.
So you'll need to loop over the results in dataSnapshot:
mDatabaseUsers.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot userSnapshot: dataSnapshot.getChildren()) {
System.out.println(userSnapshot.child("name").getValue(String.class));
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
throw databaseError.toException(); // don't ignore errors
}
});
Also see the brief example in the Firebase documentation on using a value event to get a list of results.