Add an item to a list in Firebase Database

Question

I have the following Firebase database structure. uIds is a type of List. I am trying to add another uId under uIds with

Answer 1

Not sure what you mean when you say setValue, etc require you to retrieve existing data. The basic flow for inserting new record is as follows:

private DatabaseReference mDatabase;
// get reference to your Firebase Database.
mDatabase = FirebaseDatabase.getInstance().getReference();
//and here you add a new child to your 'requests' collection
//I am assuming you have a Request model like this..
Request newRequest = new Request(some-params);
mDatabase.child("requests").child(someRequestId).setValue(newRequest);

You can take a look at basic usage guide for Saving Data on Android Firebase.

Update: Following your comment - I think what you are looking to do can be achieved like this: You use the push() method which generates a unique ID every time a new child is added to the specified Firebase reference:

Firebase newRequestRef = mDatabase.child("request").push();
newRequestRef.setValue(newRequest);

This should do it.

I hope this helps.