I have a database that looks like this:
And my code like this:
myRef.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot uniqueKey:dataSnapshot.getChildren()) {
for (DataSnapshot keysiswa:uniqueKey.getChildren()) {
for (DataSnapshot valuesiswa:keysiswa.child("nama_siswa").getChildren()) {
String c = valuesiswa.getValue().toString();
Log.i(TAG,c);
}
}
}
}
I want to take the value of "nama_siswa" but nothing happens in logcat. What is wrong with my code?
Try this code.
DatabaseReference reference = FirebaseDatabase.getInstance().getReference("siswa");
reference.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
Log.d("Name:",dataSnapshot.getValue(User.class).name); // define your pojo class
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
To get the value of nama_siswa property, please use the following code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference siswaRef = rootRef.child("siswa");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
String nama_siswa = ds.child("nama_siswa").getValue(String.class);
Log.d("TAG", nama_siswa);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
siswaRef.addListenerForSingleValueEvent(valueEventListener);
The output will be:
chandra
coba
Related
I want to show all product child details. but I was unable to do so. I am new to firebase and wish to complete my university project I need to use firebase.
each user has a single or multiple products. I can show all shops from a single user but I want to show all products from all user.
private void loadShopProducts() {
productList = new ArrayList<>();
DatabaseReference ref = FirebaseDatabase.getInstance().getReference("Users");
ref.child(shopUid).child("Products")
.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
productList.clear();
for (DataSnapshot ds : dataSnapshot.getChildren()){
ModelProduct modelProduct = ds.getValue(ModelProduct.class);
productList.add(modelProduct);
}
adapterProductBuyer = new
AdapterProductBuyer(ShopDetailsActivity.this, productList);
productRv.setAdapter(adapterProductBuyer);
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
}
Basically, I need to pull out all the children from users who are the seller.
private void loadAllProduct(){
productList = new ArrayList<>();
DatabaseReference ref = FirebaseDatabase.getInstance().getReference("Users");
ref.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
productList.clear();
for (DataSnapshot ds : dataSnapshot.getChildren()){
String uid = ""+ds.getRef().getKey();
DatabaseReference ref = (DatabaseReference) FirebaseDatabase.getInstance().getReference("Users").child(uid).child("Products");
// ref.addValueEventListener(new ValueEventListener() {
ref.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
productList.clear();
if (dataSnapshot.exists()){
for (DataSnapshot ds : dataSnapshot.getChildren()){
ModelProduct modelProduct = ds.getValue(ModelProduct.class);
productList.add(modelProduct);
}
adapterProductShow = new AdapterProductShow(MainBuyerActivity.this, productList);
showAllProductRv.setAdapter(adapterProductShow);
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
My database looks as follows, in here I want to retrieve the data inside the mylocation child (see the attached image here). But it is not working.
How to solve that?
My current code looks as this,
private void loadAddress() {
DatabaseReference ref= FirebaseDatabase.getInstance().getReference("Users");
ref.orderByChild("uid").equalTo(firebaseAuth.getUid())
.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
for(DataSnapshot ds: dataSnapshot.getChildren()){
String name=""+ds.child("name").getValue();
String lat=""+ds.child("name2").getValue();
addresstv.setText(name);
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
}
});
}
To get the data under mylocation, you use an explicit call to that child, like in the following lines of code:
String uid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference uidRef = rootRef.child("Users").child(uid);
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String name = dataSnapshot.child("mylocation").child("name2").getValue(String.class);
double latitude = dataSnapshot.child("mylocation").child("latitude").getValue(Double.class);
double longitude = dataSnapshot.child("mylocation").child("longitude").getValue(Double.class);
Log.d("TAG", name + "/" + latitude + "/" + longitude);
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
Log.d("TAG", databaseError.getMessage()); //Don't ignore errors!
}
};
uidRef.addListenerForSingleValueEvent(valueEventListener);
The result in the logcat will be:
5555/79.8571577/6.9448882
{
"History" : {
"-LIRZ4Nf2HyTTYtZEeOA" : {
"destination" : "101 Main Street, Your Town, Your Country",
"driver" : "vP9r4F2yDWRRuvKjRiQvMEXVuoK2",
"payment response" : "approved",
"rating" : 0,
"ridePrice" : 3.63,
"rider" : "C0RjB5NPZcTvWz9XiUAhpTDOK0C2",
"status" : "accepted",
"timestamp" : 1532709012
}
}
The above is the History node in my Firebase database.
My ultimate goal is to send an alert dialog once the payment response = "approved" but, in this case, when there is more than one key in the History node, the alerts run on top of each other.
What can I do so this does not happen?
The code I am using to get the key for each History entry is:
private void getPaymentResponse() {
final DatabaseReference paymentConfirmed = FirebaseDatabase.getInstance().getReference("History");
paymentConfirmed.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
ryydeKey = ds.getKey(); **<-- gets the key**
DatabaseReference response = FirebaseDatabase.getInstance().getReference("History")
.child(ryydeKey);
response.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot child : dataSnapshot.getChildren()) {
if (child.getKey().equals("payment response")) {
String response = String.valueOf(child.getValue().toString());
if (response.equals("approved")) {
proceedToPickupDialog();
}
}
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
});
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
I am assuming that the code:
for(DataSnapshot ds : dataSnapshot.getChildren()) {
ryydeKey = ds.getKey();
is getting all the keys, but all I want is the present key.
Edit
I am putting in this code and nothing is printing up. Tried logs and toasts.
DatabaseReference payRef = FirebaseDatabase.getInstance().getReference();
Query query = payRef.child("History").orderByChild("driver").equalTo(driverId).limitToLast(1);
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
String response = ds.child("payment response").getValue(String.class);
Log.e(TAG, "response = " + response);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
query.addListenerForSingleValueEvent(valueEventListener);
When you are using getChildren() method, it means that you are looping through the entire DataSnapshot object. If the DataSnapshot contains more then one child, then the alerts will run on top of each other. If you want to check only for a particular child, you need to change the code a little bit.
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference idRef = rootRef.child("History").child("-LIRZ4Nf2HyTTYtZEeOA");
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String response = dataSnapshot.child("payment response").getValue(String.class);
if(response.equalTo("approved")) {
Log.d("TAG", "Payment approved!");
} else {
Log.d("TAG", "Payment not approved!");
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
idRef.addListenerForSingleValueEvent(valueEventListener);
Using this code, you get only the response form a single child. To actually get this work done, first you need to store this value -LIRZ4Nf2HyTTYtZEeOA in a variable in order to be able to use in your reference.
Edit: This another approach using a query"
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
Query query = rootRef.child("History").orderByChild("driver").equalsTo(driverId).limitToLast(1);
ValueEventListener valueEventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
String response = dataSnapshot.child("payment response").getValue(String.class);
if(response.equalTo("approved")) {
Log.d("TAG", "Payment approved!");
}
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
query.addListenerForSingleValueEvent(valueEventListener);
I am new in android and I want to get userIDS from Firebase Database, I've tried by using this but it returns null.
By using this code
Value of Constants.ARG_CHAT_GROUP_ROOMS=Groups and Constants.NEW_NODE=newGroup
private void getMYuid() {
String senderUid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference mTest = FirebaseDatabase.getInstance().getReference();
mTest.child(Constants.ARG_CHAT_GROUP_ROOMS).child(Constants.NEW_NODE)
.child(senderUid).addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (!dataSnapshot.exists()){
Toast.makeText(ActivityChatView.this, "not exist", Toast.LENGTH_SHORT).show();
Log.e("151","ACV"+dataSnapshot);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
Log.e("139","ACV"+senderUid);
}
Database Structure is this
if you want the first one under 15052169227329_myGroupName_Hell By Anne: Your problem is that you forgot the node before "Constants.NEW_NODE"
private void getMYuid() {
String senderUid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference mTest = FirebaseDatabase.getInstance().getReference();
mTest.child(Constants.ARG_CHAT_GROUP_ROOMS).child("15052169227329_myGroupName_Hell By Anne").child(Constants.NEW_NODE)
.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (!dataSnapshot.exists()){
Toast.makeText(ActivityChatView.this, "not exist", Toast.LENGTH_SHORT).show();
Log.e("151","ACV"+dataSnapshot);
}
// You can cast this object later but it seems that that is a string and not an array
Object yourRequiredObject = dataSnapshot.child("usersIDS").getValue();
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
Log.e("139","ACV"+senderUid);
}
As i see, it's not an array it's a String. To get the userIDS, please use the following code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference yourRef = rootRef.child(Constants.ARG_CHAT_GROUP_ROOMS).child(senderUid).child(Constants.NEW_NODE);
ValueEventListener eventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String usersIDS = dataSnapshot.child("usersIDS").getValue(String.class);
Log.d("TAG", usersIDS);
//Here you can split the usersIDS String by , (comma)
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
yourRef.addListenerForSingleValueEvent(eventListener);
In which senderUid is the missing child. This child can have the value like 1505217176288_myGroupName_1 or other coresponding group names.
Here is my firebase data structure . The child "Tags" is a child of root.
final Query searchquery = mDatabase.child("Tags").orderByKey().limitToFirst(10).startAt(s.toString().toLowerCase()).endAt(s.toString().toLowerCase() + "\uf8ff");
searchquery.addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
try {
String u = dataSnapshot.child("article_name").getValue(String.class);
Toast.makeText(MainActivity.this,":/ : "+u.toString(),Toast.LENGTH_LONG).show();
}catch (Exception tg){
Toast.makeText(MainActivity.this,tg.toString(),Toast.LENGTH_LONG).show();
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
I want to get the value of child "article_name" . I used the code above . But it is returning null .
Please use this code:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference tagsRef = rootRef.child("Tags");
ValueEventListener eventListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
String article_name = ds.child("article_name").getValue(String.class);
Log.d("TAG", tagsRef);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {}
};
tagsRef.addListenerForSingleValueEvent(eventListener);
The output will be:
Blood Circulation
Dummy Article
Also don't forget to use names for the keys that does not contain any spaces. So you need to change blood circulation in blood_circulation or bloodCirculation