Download an audio file in .NET MAUI

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using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;

namespace NightClub.ViewModels;

public partial class MusicPlayerViewModel : ObservableObject
{
    #region Properties
    #endregion

    public MusicPlayerViewModel()
    {
    }

    #region Commands
    #endregion
}

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...
// This using is mandatory to resolve the definition of MusicPlayerViewModel
using NightClub.ViewModels;

namespace NightClub.Views;
public class MusicPlayerView : ContentPage
{
    public MusicPlayerView()
    {
        Console.WriteLine("[NightClub] MusicPlayerView - Constructor");

        // Here is where the association is happening
        BindingContext = new MusicPlayerViewModel();

        NavigationPage.SetHasNavigationBar(this, false);
        BackgroundColor = Colors.DimGray;
        ...
    }
    ...
}

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namespace NightClub.Models;

public class MusicTrack
{
    public string AudioURL { get; set; }
    public string AudioDownloadURL { get; set; }
    public string Title { get; set; }
    public string Author { get; set; }
}

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...
using NightClub.Models; // This is required to resolve MusicTrack object!

namespace NightClub.ViewModels;

public partial class MusicPlayerViewModel : ObservableObject
{
    #region Properties

    [ObservableProperty]
    MusicTrack currentTrack;

    #endregion
    ...
}

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public MusicPlayerViewModel()
{
    CurrentTrack = new MusicTrack()
    {
        AudioURL = "https://prod-1.storage.jamendo.com/?trackid=1890762&format=mp31&from=b5bSbOTAT1kXawaT8EV9IA%3D%3D%7CGcDX%2BeejT3P%2F0CfPwtSyYA%3D%3D",
        AudioDownloadURL = "https://prod-1.storage.jamendo.com/download/track/1890762/mp32/",
        Author = "Alfonso Lugo",
        Title = "Baila",
    };
}

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...
using NightClub.Models; // This is required to resolve MusicTrack object!

namespace NightClub.Views;
public class MusicPlayerView : ContentPage
{
    ...
    #region MusicPlayer

    MediaElement MusicPlayer = new MediaElement();

    // And here's the new definition for that method...
    void InitMusicPlayer()
    {
        MusicPlayer.ShouldAutoPlay = true;

        // ... with the binding logic on the MusicPlayer.
        MusicPlayer.Bind(
            MediaElement.SourceProperty,
            nameof(MusicPlayerViewModel.CurrentTrack),
            convert: (MusicTrack musicTrack) => MediaSource.FromUri(musicTrack.AudioURL)
            );
    }

    #endregion
    ...
}

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#region Media Control Panel
    ...
    // The “=>” sign has been replaced with “=”
    ImageButton DownloadButton = new ImageButton
    {
        CornerRadius = 5,
        HeightRequest = 25,
        WidthRequest = 25,
        Source = "download.png",
        BackgroundColor = Colors.Black
    } .BindCommand("DownloadCurrentTrackCommand"); // And here's the command to associate

#endregion

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...
using CommunityToolkit.Maui.Alerts; // This "using" is new...
using CommunityToolkit.Maui.Storage; // ... and this one as well !

namespace NightClub.ViewModels;
public partial class MusicPlayerViewModel : ObservableObject
{
    ...
    #region Commands

    [RelayCommand]
    async Task DownloadCurrentTrack(CancellationToken cancellationToken)
    {
        await Toast
            .Make($"[TEST] You have successfully downloaded \"{CurrentTrack.Title} - {CurrentTrack.Author}\"!")
            .Show(cancellationToken);
    }

    #endregion
}

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#region Commands

[RelayCommand]
async Task DownloadCurrentTrack(CancellationToken cancellationToken)
{
    // We raise an exception when cancellation is requested
    cancellationToken.ThrowIfCancellationRequested();

    try
    {
        // We need an HTTP client to send our request through the network
        HttpClient client = new HttpClient();
        client.MaxResponseContentBufferSize = 100000000; // We can download up to ~100MB of data per file!

        // We send an HTTP request to the link for downloading audio
        using var httpResponse =
            await client.GetAsync(
                new Uri(CurrentTrack.AudioDownloadURL), cancellationToken);

        httpResponse.EnsureSuccessStatusCode();

        var downloadedImage = await httpResponse.Content.ReadAsStreamAsync(cancellationToken);

        try
        {
            string fileName = $"{CurrentTrack.Title} - {CurrentTrack.Author}.mp3";

            // The retrieved data is then transferred to a file
            // Note: we need CommunityToolkit.Maui to be updated to 5.1.0 at least
            var fileSaveResult = await FileSaver.SaveAsync(fileName, downloadedImage, cancellationToken);

            fileSaveResult.EnsureSuccess();

            await Toast.Make($"File saved at: {fileSaveResult.FilePath}").Show(cancellationToken);
        }
        catch (Exception ex)
        {
            await Toast.Make($"Cannot save file because: {ex.Message}").Show(cancellationToken);
        }
    }
    catch (Exception ex)
    {
        await Toast.Make($"Cannot download file because: {ex.Message}").Show(cancellationToken);
    }
}

#endregion

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<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" android:maxSdkVersion="32" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />