How to move Firebase child from one node to another in Android?

Question

I am working on a project where user request for our valet services and on the other end valet accepts request.

I am using using Firebase as backend and on request c

Answer 1

you can listen to value event on your child you want to copy it ,, and #onDataChange get reference of new child and set value dataSnapshot to this child like below sample code

FirebaseDatabase.getInstance().getReference("childYouWantToCopy")
                    .addListenerForSingleValueEvent(new ValueEventListener() {
                @Override
                public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                    FirebaseDatabase.getInstance().getReference("ChildCopyTo").setValue(dataSnapshot.getValue());
                }

                @Override
                public void onCancelled(@NonNull DatabaseError databaseError) {

                }
            });

Answer 2

As of compile firebase-database:11.0.1, this is the same function with the new class references (https://firebase.google.com/support/guides/firebase-android July 05 2017)

private void moveGameRoom(final DatabaseReference fromPath, final DatabaseReference toPath) {
        fromPath.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                toPath.setValue(dataSnapshot.getValue(), new DatabaseReference.CompletionListener() {
                    @Override
                    public void onComplete(DatabaseError firebaseError, DatabaseReference firebase) {
                        if (firebaseError != null) {
                            System.out.println("Copy failed");
                        } else {
                            System.out.println("Success");

                        }
                    }
                });

            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });
    }

Answer 3

I recommend using this :

public void moveFirebaseRecord(Firebase fromPath, final Firebase toPath)
{
    fromPath.addListenerForSingleValueEvent(new ValueEventListener()
    {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot)
        {
            toPath.setValue(dataSnapshot.getValue(), new Firebase.CompletionListener()
            {
                @Override
                public void onComplete(FirebaseError firebaseError, Firebase firebase)
                {
                    if (firebaseError != null)
                    {
                        System.out.println("Copy failed");
                    }
                    else
                    {
                        System.out.println("Success");
                    }
                }
            });
        }

        @Override
        public void onCancelled(FirebaseError firebaseError)
        {
            System.out.println("Copy failed");
        }
    });
}

This come from this source : https://gist.github.com/katowulf/6099042 . I used it several times in my JavaEE code and also in my android app.

You pass your fromPath and toPath. This is a copy tought and not a move, so the original will remain at his original place too. If you would like to delete, you can do a set value on the fromPath just after the System.out.println("Success"); .

Answer 4

If you want to perform a move which also erases the original, you might make use of the following snippet:

// In this piece of code, "fromPath" and "toPath" parameters act like directories.
private void removeFromFirebase(final DatabaseReference fromPath, final DatabaseReference toPath, final String key) {
    fromPath.child(key).addListenerForSingleValueEvent(new ValueEventListener() {
        // Now "DataSnapshot" holds the key and the value at the "fromPath".
        // Let's move it to the "toPath". This operation duplicates the
        // key/value pair at the "fromPath" to the "toPath".
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            toPath.child(dataSnapshot.getKey())
                    .setValue(dataSnapshot.getValue(), new DatabaseReference.CompletionListener() {
                        @Override
                        public void onComplete(DatabaseError databaseError, DatabaseReference databaseReference) {
                            if (databaseError == null) {
                                Log.i(TAG, "onComplete: success");
                                // In order to complete the move, we are going to erase
                                // the original copy by assigning null as its value.
                                fromPath.child(key).setValue(null);
                            }
                            else {
                                Log.e(TAG, "onComplete: failure:" + databaseError.getMessage() + ": "
                                        + databaseError.getDetails());
                            }
                        }
                    });
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
            Log.e(TAG, "onCancelled: " + databaseError.getMessage() + ": "
                    + databaseError.getDetails());
        }
    });
}