.NET MAUI System.ObjectDisposedException: „Auf ein entsorgtes Objekt kann nicht zugegriffen werden.“ Objektname: „Micros ⇐ C#

[Anonymous]

Ich habe ein großes Problem mit meiner App, sie stürzt mit dem Fehler im Titel ab.
Ich verwende WeakMessageReferences.
Das ist Die Klasse, die ich erstellt habe:

Code: Select all

using CommunityToolkit.Mvvm.Messaging;

namespace NuesWarehouseMobile.Utilities
{
internal static class RefreshManager
{
public static void RequestRefresh(string viewName)
{
WeakReferenceMessenger.Default.Send(new RefreshViewMessage(viewName));
}

public static void Register(TRecipient recipient, Action action) where TRecipient : class
{
WeakReferenceMessenger.Default.Register(recipient, (r, m) => action(m));
}

public static void Unregister(TRecipient recipient) where TRecipient : class
{
WeakReferenceMessenger.Default.Unregister(recipient);
}
}

public class RefreshViewMessage
{
public string ViewName { get; }

public RefreshViewMessage(string viewName)
{
ViewName = viewName;
}
}

}

Die Verwendung von WeakReferences generiert die Ausnahme.
Ich habe versucht, die Ansichten zwischenzuspeichern, damit sie nicht verworfen werden, aber es funktioniert nicht.
Ich habe versucht, einige starke Referenzen für das Gleiche zu erstellen, aber es funktioniert nicht.
Ich habe versucht, verschiedene Methoden zu verwenden, um meine Ansichten zu aktualisieren, aber nur die Nachrichten funktionieren, also muss ich dabei bleiben.
Logik anzeigen:

Code: Select all

    using CommunityToolkit.Mvvm.Messaging;
using NuesWarehouse.Core.Dtos;
using NuesWarehouseMobile.Core.Interfaces.Services;
using NuesWarehouseMobile.Utilities;
using System.Collections.ObjectModel;
using System.Diagnostics;
using System.Windows.Input;

namespace NuesWarehouseMobile.MenuView;

public partial class DocumentiDaEvadereView : ContentView
{
private readonly IDocumentService _documentService;
private int currentPage = 1;
private int perPage = 20;
private string stato = "Aperto-Picking-Parzialmente Evaso"; //SPAZIO VUOTO
private string tipoDoc = "OrdineVendita";

private bool _isLoading;
public bool IsLoading
{
get => _isLoading;
set
{
_isLoading = value;
OnPropertyChanged(nameof(IsLoading));
}
}

public ObservableCollection Documents { get; set; }

public ICommand LoadDocumentsCommand { get; }
public ICommand NextPageCommand { get; }
public ICommand PreviousPageCommand { get; }

private int _currentPageDisplay;
public int CurrentPageDisplay
{
get => _currentPageDisplay;
set
{
_currentPageDisplay = value;
OnPropertyChanged();
}
}

public DocumentiDaEvadereView()
{
InitializeComponent();

RefreshManager.Register(this, OnRefreshViewMessageReceived);

IsLoading = true;
_documentService = Application.Current.Handler.MauiContext.Services.GetService();
Documents = new ObservableCollection();
LoadDocumentsAsync();

LoadDocumentsCommand = new Command(async () => await LoadDocumentsAsync());
NextPageCommand = new Command(async () => await LoadNextPageAsync());
PreviousPageCommand = new Command(async () =>  await LoadPreviousPageAsync());

//CurrentPageDisplay = currentPage;

double screenHeight = DeviceDisplay.MainDisplayInfo.Height / DeviceDisplay.MainDisplayInfo.Density;
double gridHeight = screenHeight * 0.6;
DocumentsDataGrid.HeightRequest = gridHeight;

BindingContext = this;
// Carica la prima pagina
LoadDocumentsCommand.Execute(null);

IsLoading = false;
}

private async Task LoadDocumentsAsync(int page = 1)
{

var documents = await _documentService.GetDocumentsByPage(page, perPage, tipoDoc, stato);
Documents.Clear();
foreach (var document in documents)
{
if (document.Stato == "Evaso")
{
document.StatoColor = "Green";
}
else if (document.Stato == "Parzialmente Evaso")
{
document.StatoColor = "Orange";
}
else
{
document.StatoColor = "Yellow";
}
Documents.Add(document);
}
CurrentPageDisplay = currentPage;

DocumentsDataGrid.ItemsSource = null;
DocumentsDataGrid.ItemsSource = Documents;
}

private async Task LoadNextPageAsync()
{
currentPage++;
await LoadDocumentsAsync(currentPage);
}

private async Task LoadPreviousPageAsync()
{
if (currentPage > 1)
{
currentPage--;
await LoadDocumentsAsync(currentPage);
}
}

// Metodo per aprire una nuova view
private void ApriNuovaPaginaCommand(object sender, EventArgs e)
{
IsLoading = true;
var button = sender as Button;
if (button?.CommandParameter is string documentId)
{
Debug.WriteLine(documentId);
Navigation.PushAsync(new EvasioneDocumentoPage(documentId));
}
else
{
Debug.WriteLine("====ATTENZIONE, PARAMETRO documentId NON PASSATO CORRETTAMENTE====");
}
IsLoading = false;

}

private void OnRefreshViewMessageReceived(RefreshViewMessage message)
{
if (message.ViewName == "EvasioneDocumento") // Controllo parametro
{
Debug.WriteLine("Messaggio ricevuto in DocumentsView! Aggiorno i documenti...");
_ = LoadDocumentsAsync(1); // Ricarica i documenti
}
}

~DocumentiDaEvadereView()
{
// Deregistrazione per evitare memory leaks
RefreshManager.Unregister(this);
}
}