Initial commit of WinUI3 Shell32 helpers <WIP>

[tajbender]

Initial commit of WinUI3 Shell32 helpers.

For Reference only.

[tajbender]

This is a stub actually.

More coming soon.

[tajbender]

Hello, @dahall

I'm working on the WinUI3 stuff using the brand new IconExtractor again.

When enumerating some special folders, the IconExtractor throws errors when then trying to get the DisplayName:

Code involved at public void ExtractChildItems( ... ):

        Debug.Assert(targetFolder.IsFolder);
        Debug.Assert(targetFolder.ShellItem.PIDL != null);
        var shItemId = targetFolder.ShellItem.PIDL;
        var shFolder = new ShellFolder(shItemId);
        var shellIconExtractor = new ShellIconExtractor(shFolder);
        shellIconExtractor.IconExtracted += (sender, args) =>
        {
            var shItem = new ShellItem(args.ItemID);
            var ebItem = new ExplorerBrowserItem(shItem);

            DispatcherQueue.TryEnqueue(() =>
            {
                CurrentFolderItems.Add(ebItem);
            });
        };
        shellIconExtractor.IconExtracted += iconExtOnIconExtracted;
        shellIconExtractor.Complete += iconExtOnComplete;
        shellIconExtractor.Start();

...

    public ExplorerBrowserItem(ShellItem? shItem, bool isSeparator = false)
    {
        ShellItem = new ShellItem(shItem.PIDL);
        DisplayName = ShellItem.Name ?? ":error: <DisplayName.get()>";
        IsExpanded = false;
        // todo: If IsSelected, add overlay of opened folder icon to TreeView optionally
        IsSelected = false;
    }

The folders that don't work are virtual ones: Home, This PC, Network.

You can (hopefully) build the branch involved from this:

• https://github.com/tajbender/electrifier.v1.24/tree/IconExtractor-Branch

You can see the result here:

• https://1drv.ms/v/s!AhSOruD5hLFbhr87UzH6vGqfPHmiKA?e=2SZ94j

Any ideas? Didn't debug into your code, cause I'm not privileged enough to understand it 🤣

Keep in mind, that there are no icons involved, no navigation is working ⚒

Any thoughts on this?

Thank you very much,
regards,
tajbender

[tajbender]

You don't have to care. I'm bringing in Unit-Tests for this Issue, to track it down...

My 1st Unit Testing 👅 🥇

[tajbender]

Hello, @dahall

I've made some progress with the Shell controls for WinUI the last weeks.

I will update this pull request soon, I guess. In the meantime, a made a little class diagram from what I've got so far:

---

As one can see, It's the same class hierarchy native ExplorerBrowser is using.

There is one difference though: I'm using abstract classes for what represents a single shell Item.

namespace electrifier.Controls.Vanara.Contracts;

[DebuggerDisplay($"{{{nameof(ToString)}(),nq}}")]
public abstract class AbstractBrowserItem<T>(bool isFolder, List<AbstractBrowserItem<T>>? childItems)
{
    public readonly bool IsFolder = isFolder;       // WARN: TODO: Check this. If unknown, then find it out!  ... edit: or use virtual function for this!
    public readonly List<AbstractBrowserItem<T>> ChildItems = childItems ?? [];
    public SoftwareBitmapSource SoftwareBitmapSource = isFolder
        ? IShellNamespaceService.FolderBitmapSource
        : IShellNamespaceService.DocumentBitmapSource;
    public new string ToString() => $"AbstractBrowserItem(<{typeof(T)}>(isFolder {isFolder}, childItems {childItems})";
}

[DebuggerDisplay($"{{{nameof(ToString)}(),nq}}")]
public abstract class AbstractBrowserItemCollection<T> : IEnumerable<AbstractBrowserItem<T>>, IList<AbstractBrowserItem<T>>
{
    //protected readonly ShellItem? _parentOwnerItem;
    protected readonly IList<AbstractBrowserItem<T>> Collection = [];

    AbstractBrowserItem<T> IList<AbstractBrowserItem<T>>.this[int index] { get => Collection[index]; set => Collection[index] = value; }
    int ICollection<AbstractBrowserItem<T>>.Count => Collection.Count;
    bool ICollection<AbstractBrowserItem<T>>.IsReadOnly => false;
    void ICollection<AbstractBrowserItem<T>>.Add(AbstractBrowserItem<T> item) => Collection.Add(item);
    void ICollection<AbstractBrowserItem<T>>.Clear() => Collection.Clear();
    bool ICollection<AbstractBrowserItem<T>>.Contains(AbstractBrowserItem<T> item) => Collection.Contains(item);
    void ICollection<AbstractBrowserItem<T>>.CopyTo(AbstractBrowserItem<T>[] array, int arrayIndex) => Collection.CopyTo(array, arrayIndex);
    IEnumerator<AbstractBrowserItem<T>> IEnumerable<AbstractBrowserItem<T>>.GetEnumerator() => Collection.GetEnumerator();
    IEnumerator IEnumerable.GetEnumerator() => Collection.GetEnumerator();
    int IList<AbstractBrowserItem<T>>.IndexOf(AbstractBrowserItem<T> item) => Collection.IndexOf(item);
    void IList<AbstractBrowserItem<T>>.Insert(int index, AbstractBrowserItem<T> item) => Collection.Insert(index, item);
    bool ICollection<AbstractBrowserItem<T>>.Remove(AbstractBrowserItem<T> item) => Collection.Remove(item);
    void IList<AbstractBrowserItem<T>>.RemoveAt(int index) => Collection.RemoveAt(index);

    public new string ToString() => $"AbstractBrowserItemCollection(<{typeof(T)}>(number of child items: {Collection.Count})";
}

This actually leads to the following (wip) descent BrowserItem of AbstractBrowserItem<ShellItem>:

public class BrowserItem(Shell32.PIDL pidl, bool isFolder, List<AbstractBrowserItem<ShellItem>>? childItems = default)
    : AbstractBrowserItem<ShellItem>(isFolder, childItems), INotifyPropertyChanged
{
    public readonly Shell32.PIDL PIDL = new(pidl);
    public string DisplayName => ShellItem.GetDisplayName(ShellItemDisplayString.NormalDisplay) ?? ShellItem.ToString();
    public ShellItem ShellItem = new(pidl);
    public new ObservableCollection<BrowserItem> ChildItems = [];
    public static BrowserItem FromPIDL(Shell32.PIDL pidl) => new(pidl, false);
    public static BrowserItem FromShellFolder(ShellFolder shellFolder) => new(shellFolder.PIDL, true);
    public static BrowserItem FromKnownFolderId(Shell32.KNOWNFOLDERID knownItemId) => new(new ShellFolder(knownItemId).PIDL, true);
    public Task<int> Enumerate() {}
    public event PropertyChangedEventHandler? PropertyChanged;
    protected virtual void OnPropertyChanged([CallerMemberName] string? propertyName = null) { }
    protected bool SetField<T>(ref T field, T value, [CallerMemberName] string? propertyName = null) { }
}

As one can see, it's pretty straightforward. However, I'm not sure how massive the impact of using INotifyPropertyChanged will be.

@dahall: But, in my humble opinion, there should be none, what're your ideas on this?

I'm writing things down so no one is wondering why I'm using such an approach. That is, cause i hope to get things abstract enough to have a generic platform for any structured content, like databases etc. pp.

Regards and thanks for readings,

tajbender