realtimedatabasefirabase.java

FirebaseDatabase.getInstance().setPersistenceEnabled(true);

final FirebaseDatabase database = FirebaseDatabase.getInstance();
final DatabaseReference showWallet = database.getReference("donation").child("show_wallet");

showWallet.addValueEventListener(new ValueEventListener() {
    @Override
    public void onDataChange(DataSnapshot dataSnapshot) {
        Boolean value = dataSnapshot.getValue(Boolean.class);

        if (value)
            llAboutDonate.setVisibility(View.VISIBLE);
        else
            llAboutDonate.setVisibility(View.GONE);

        showWallet.keepSynced(true);
    }

    @Override
    public void onCancelled(DatabaseError error) {
        // Failed to read value
        Log.w(TAG, "Failed to read value.", error.toException());
    }
});