Get specific categories of data from firebase… here is a solution to the problem.
Get specific categories of data from firebase
I
want to categorize the data in the Firebase live database and then select them by category to display in different parts of my android View, but I don’t know where to start. I’m new to Firebase, I just know how to extract data, push it to the Firebase database, and display all the acquired data.
My question is: is this possible? If so, what should I do?
Thanks
Solution
If you have this database:
Animals
randomId
name: dog
category: mammal
randomId
name: snake
category: reptile
randomId
name: elephants
category: mammal
You can then query by class:
DatabaseReference ref=FirebaseDatabase.getInstance().getReference("Animals");
Query query=ref.orderByChild("category").equalTo("mammal");
query.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot datas: dataSnapshot.getChildren()){
String name=datas.child("name").getValue().toString();
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
This will retrieve all names with categories equal to mammals.
Check here too:
https://firebase.google.com/docs/database/android/lists-of-data