Reading a value (string) from real-time database firebase and save it into a list of strings
I want to read a data field from my firebase and save the value inside a list of a strings. I keep getting the null error.
This is my code:
List<String> names;
void alluser () async {
DatabaseReference db = await
FirebaseDatabase.instance.reference().child("users");
db.once().then((DataSnapshot snapshot){
Map<dynamic, dynamic> values= snapshot.value;
values.addAll(names2);
});
}
After that I want to call a function to print all the name ( I don't want to print all the names inside the " alluser " function since I want to have the names in a list of strings.
void printall (){
for (int i = 0 ; i< names2.length; i++){
print("hello");
print( names2["names"]);
}
}
android 
firebase firebase-realtime-database 
flutter edited Nov 22 at 22:48
Frank van Puffelen
226k27369396
asked Nov 22 at 22:11
Manaf
14
add a comment |
I want to read a data field from my firebase and save the value inside a list of a strings. I keep getting the null error.
This is my code:
List<String> names;
void alluser () async {
DatabaseReference db = await
FirebaseDatabase.instance.reference().child("users");
db.once().then((DataSnapshot snapshot){
Map<dynamic, dynamic> values= snapshot.value;
values.addAll(names2);
});
}
After that I want to call a function to print all the name ( I don't want to print all the names inside the " alluser " function since I want to have the names in a list of strings.
void printall (){
for (int i = 0 ; i< names2.length; i++){
print("hello");
print( names2["names"]);
}
}
edited Nov 22 at 22:48
Frank van Puffelen
226k27369396
asked Nov 22 at 22:11
Manaf
14
read the docs => firebase.google.com/docs/database/android/read-and-write
– Har Kal
Nov 22 at 23:04
Can you try - snapshot.data instead of snapshot.value
– anmol.majhail
Nov 23 at 7:35
@anmol.majhail it doesn't work sir. it says " data " isn't defined on the class DataSnapShot.
– Manaf
Nov 23 at 11:55
add a comment |
I want to read a data field from my firebase and save the value inside a list of a strings. I keep getting the null error.
This is my code:
List<String> names;
void alluser () async {
DatabaseReference db = await
FirebaseDatabase.instance.reference().child("users");
db.once().then((DataSnapshot snapshot){
Map<dynamic, dynamic> values= snapshot.value;
values.addAll(names2);
});
}
After that I want to call a function to print all the name ( I don't want to print all the names inside the " alluser " function since I want to have the names in a list of strings.
void printall (){
for (int i = 0 ; i< names2.length; i++){
print("hello");
print( names2["names"]);
}
}
edited Nov 22 at 22:48
Frank van Puffelen
226k27369396
asked Nov 22 at 22:11
Manaf
14
I want to read a data field from my firebase and save the value inside a list of a strings. I keep getting the null error.
This is my code:
List<String> names;
void alluser () async {
DatabaseReference db = await
FirebaseDatabase.instance.reference().child("users");
db.once().then((DataSnapshot snapshot){
Map<dynamic, dynamic> values= snapshot.value;
values.addAll(names2);
});
}
After that I want to call a function to print all the name ( I don't want to print all the names inside the " alluser " function since I want to have the names in a list of strings.
void printall (){
for (int i = 0 ; i< names2.length; i++){
print("hello");
print( names2["names"]);
}
}
edited Nov 22 at 22:48
Frank van Puffelen
226k27369396
asked Nov 22 at 22:11
Manaf
14
edited Nov 22 at 22:48
Frank van Puffelen
226k27369396
asked Nov 22 at 22:11
Manaf
14
edited Nov 22 at 22:48
Frank van Puffelen
226k27369396
edited Nov 22 at 22:48
Frank van Puffelen
226k27369396
edited Nov 22 at 22:48
Frank van Puffelen
226k27369396
226k27369396
asked Nov 22 at 22:11
Manaf
14
asked Nov 22 at 22:11
Manaf
14
asked Nov 22 at 22:11
Manaf
14
14
read the docs => firebase.google.com/docs/database/android/read-and-write
– Har Kal
Nov 22 at 23:04
Can you try - snapshot.data instead of snapshot.value
– anmol.majhail
Nov 23 at 7:35
@anmol.majhail it doesn't work sir. it says " data " isn't defined on the class DataSnapShot.
– Manaf
Nov 23 at 11:55
add a comment |
read the docs => firebase.google.com/docs/database/android/read-and-write
– Har Kal
Nov 22 at 23:04
Can you try - snapshot.data instead of snapshot.value
– anmol.majhail
Nov 23 at 7:35
@anmol.majhail it doesn't work sir. it says " data " isn't defined on the class DataSnapShot.
– Manaf
Nov 23 at 11:55
read the docs => firebase.google.com/docs/database/android/read-and-write
– Har Kal
Nov 22 at 23:04
read the docs => firebase.google.com/docs/database/android/read-and-write
– Har Kal
Nov 22 at 23:04
Can you try - snapshot.data instead of snapshot.value
– anmol.majhail
Nov 23 at 7:35
Can you try - snapshot.data instead of snapshot.value
– anmol.majhail
Nov 23 at 7:35
@anmol.majhail it doesn't work sir. it says " data " isn't defined on the class DataSnapShot.
– Manaf
Nov 23 at 11:55
@anmol.majhail it doesn't work sir. it says " data " isn't defined on the class DataSnapShot.
– Manaf
Nov 23 at 11:55
add a comment |
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read the docs => firebase.google.com/docs/database/android/read-and-write
– Har Kal
Nov 22 at 23:04
Can you try - snapshot.data instead of snapshot.value
– anmol.majhail
Nov 23 at 7:35
@anmol.majhail it doesn't work sir. it says " data " isn't defined on the class DataSnapShot.
– Manaf
Nov 23 at 11:55