public override async void OnAppear(params object[] args) { if (string.IsNullOrWhiteSpace(_settingServicce.Token)) { _nav.Init <LoginViewModel>(); } else { _httpFactory.LoggedIn(_settingServicce.Token); var res = await _memberHandler.TouchLogin(); if (res == null) { _settingServicce.Token = string.Empty; _httpFactory.Logout(); _nav.NavigateTo <LoginViewModel>(); } else { AppService.CurrentUser = res; AppService.HasCRRole = res.ClassRepresentative; _nav.Init <HomeViewModel>(); if (AppService.CurrentUser.Batch != null) { _platformService.SubsubcribeTopics(AppService.CurrentUser.Batch.Name); } } } }