protected override async void OnNavigatedTo(NavigationEventArgs e) { int?issue_id = e.Parameter as int?; if (issue_id != null && !App.Client.Issues.TryGetValue(issue_id.Value, out Issue)) { Issue = await Issues.Get(issue_id.Value); if (Issue.Id == issue_id.Value) { App.Client.Issues.Add(issue_id.Value, Issue); } } }