Retrieve and display all nodes from the Firebase database

Question

Retrieve and display all nodes from the Firebase database

Having trouble retrieving data from Firebase

This is my attempted solution :

DatabaseReference databaseRef = FirebaseDatabase.instance.reference();
await databaseRef.child('...').once().then((DataSnapshot snapshot) {
  print(snapshot.value);

});

Outcome (SUCCESSFUL) :

https://i.sstatic.net/HguUT.png

The data structure looks like this:

 id1
    key1 = val1
 id2
    key2 = val2

I want to retrieve each value (e.g. val1, val2, etc.)

I attempted the following:

  snapshot.value.forEach((d) {
    //print(d);
  });

However, I encountered this issue:

https://i.sstatic.net/UOsBE.png Any suggestions?

javascript firebase firebase-realtime-database flutter

Answer 1

Answer №1

Currently, there is no direct way to iterate through the child nodes of a DataSnapshot in Flutter. For more information, refer to this previously raised issue.

If the order of iteration is not important, you can extract a Map from the snapshot and then iterate over it:

Map<dynamic,dynamic> map = snapshot.value;
map.forEach((key, value) { print('$key: $value'); });

Update: As of mid-2021, the DataSnapshot class now includes a children property, allowing you to finally do:

snapshot.children.forEach((child) {
  print(child.value);
});

Answer 2

Currently, there is no direct way to iterate through the child nodes of a DataSnapshot in Flutter. For more information, refer to this previously raised issue.

If the order of iteration is not important, you can extract a Map from the snapshot and then iterate over it:

Map<dynamic,dynamic> map = snapshot.value;
map.forEach((key, value) { print('$key: $value'); });

Update: As of mid-2021, the DataSnapshot class now includes a children property, allowing you to finally do:

snapshot.children.forEach((child) {
  print(child.value);
});

Retrieve and display all nodes from the Firebase database

Answer №1

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