SelectPhoneCodePopup.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Maui.Controls;
using NeuroAccessMaui.Services;
using NeuroAccessMaui.Services.Data;
 
namespace NeuroAccessMaui.UI.Popups
{
    public partial class SelectPhoneCodePopup : BasePopup, IDisposable
    {
        private readonly TaskCompletionSource<ISO_3166_Country?> result = new(TaskCreationOptions.RunContinuationsAsynchronously);
        private CancellationTokenSource? cancellationTokenSource;
        private bool isDisposed;
 
        public Task<ISO_3166_Country?> Result => this.result.Task;
 
        public static ISO_3166_Country[] Countries => ISO_3166_1.Countries;
 
        public SelectPhoneCodePopup()
        {
            this.InitializeComponent();
            this.BindingContext = this;
            this.InnerSearchBar.Text = string.Empty;
        }
 
        private void SearchBar_TextChanged(object? sender, TextChangedEventArgs e)
        {
            if (string.IsNullOrEmpty(e.NewTextValue))
            {
                this.InnerListView.ItemsSource = Countries;
                return;
            }
 
            this.cancellationTokenSource?.Cancel();
            this.cancellationTokenSource = new CancellationTokenSource();
            CancellationToken token = this.cancellationTokenSource.Token;
 
            Task.Run(() =>
            {
                IEnumerable<ISO_3166_Country> filtered = Countries.Where(country =>
                    country.Name.Contains(e.NewTextValue, StringComparison.OrdinalIgnoreCase)
                    || string.Equals(country.Alpha2, e.NewTextValue, StringComparison.OrdinalIgnoreCase)
                    || string.Equals(country.Alpha3, e.NewTextValue, StringComparison.OrdinalIgnoreCase)
                    || country.DialCode.Contains(e.NewTextValue, StringComparison.OrdinalIgnoreCase));
 
                this.Dispatcher.Dispatch(() =>
                {
                    if (!token.IsCancellationRequested)
                    {
                        this.InnerListView.ItemsSource = filtered;
                    }
                });
            }, token);
        }
 
        private async void InnerListView_SelectionChanged(object? sender, SelectionChangedEventArgs e)
        {
            if (this.InnerListView.SelectedItem is ISO_3166_Country selected)
            {
                this.result.TrySetResult(selected);
                await ServiceRef.PopupService.PopAsync();
            }
        }
 
        public override async Task OnDisappearingAsync()
        {
            this.result.TrySetResult(null);
            await base.OnDisappearingAsync();
        }
 
        protected virtual void Dispose(bool disposing)
        {
            if (!this.isDisposed)
            {
                if (disposing)
                {
                    this.cancellationTokenSource?.Dispose();
                    this.cancellationTokenSource = null;
                }
 
                this.isDisposed = true;
            }
        }
 
        public void Dispose()
        {
            this.Dispose(true);
            GC.SuppressFinalize(this);
        }
    }
}