help with filering

Question

Hello

I have a weird issue, I am filtering my notebooks in the firebasService class, and that is working fine and I can see it in my collectionView

But when I click a notebook, I supposedly filter with this code

   public async void ReadAsync(string ChildName, string NotebookId = "") {

            var list = await Client.Child(ChildName)
                 .OnceAsync<NotebookNote>();

            var collection = new List<NotebookNote>();

            foreach (var item in list) {
                NotebookNote notebookNote = null;
                notebookNote = Convert(ChildName, item);
                collection.Add(notebookNote);
            }

            if (ChildName.Equals(App.Notes)) {
                collection.Where(n => ((Note)n).NotebookId == NotebookId).ToList();
            } else {
                collection = collection.Where(n => n.UserID == Preferences.Get(App.UserID, string.Empty)).ToList();
            }
            FireBaseNotebooks.Clear();
            foreach (var element in collection) {
                FireBaseNotebooks.Add(element);
            }

As you can see I check if the child name is a note, and I also send the Notebook as a parameter because the query is bring me all the notes from the notebook that has this specific id

https://github.com/eduardoagr/DuoNotes

Answer 1

Hello,

Welcome to our Microsoft Q&A platform!

You're getting RecivedSelectedNotebook as null in constructor because

It is populated with value in RecivedSelectedNotebookAccion , RecivedSelectedNotebookAccion is an Action , here it is used as a callback , it is only triggered when clicking on the specific note , but before you clicking on it , the viewmodel has already finished its initialization .

Refer to

https://stackoverflow.com/a/22024979/8187800.

Best Regards,

Cole Xia

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