private async void btnPCompleted_Click(object sender, RoutedEventArgs e) { if (PC.FinishProject(P) != null) { rtbCommentHistory.Document.Blocks.Add(CC.AddProjectComment(P.idProject, "The user " + MC.SearchMember(Environment.UserName).displayName + " has marked the project as completed.", MC.SearchMember(Environment.UserName).idMember)); var ProjectView = new ProjectView(); this.Content = ProjectView; } else { await metroWindow.ShowMessageAsync("Attention", "Project can not be updated"); } }