private Document GetThing(string address) { var getThingReq = data.Get("projects/sipp-1f4c4/databases/(default)/documents/data/step/things/" + address); try { Document doc = getThingReq.Execute(); if (doc == null) { MessageBox.Show("Can't find device"); return(null); } return(doc); } catch (Google.GoogleApiException e) { Dispatcher.BeginInvoke(new Action(() => { LoadingCover.Visibility = Visibility.Hidden; CoverText.Visibility = Visibility.Hidden; })); MessageBox.Show(e.ToString()); return(null); } }