Code Quality: Removed ISidebarViewModel

[0x5bfa]

Resolved / Related Issues

This is part of the phase 1 mentioned in #17970 (comment)

• Code Quality: Broader SidebarView control usage #15283

Steps used to test these changes

Check if the click functionalities are the same as those in the main branch.

• Right click on an item
• Right click on empty space
• Click on an item

[sentry]

Bug: The async event handler SidebarControl_ItemDropped is missing a required deferral, which can cause the drag operation's data to become invalid before async work finishes.
_{Severity: HIGH | Confidence: High}

🔍 Detailed Analysis

The SidebarControl_ItemDropped event handler is an async method that performs significant asynchronous work, such as file operations and database updates, via SidebarAdaptiveViewModel.HandleItemDroppedAsync. However, it fails to acquire a deferral from the ItemDroppedEventArgs. In the WinUI drag-and-drop API, a deferral is necessary to prevent the operating system from cleaning up the drag operation's data context before the asynchronous work completes. Without it, the DataPackageView could be invalidated mid-operation, leading to failed drop actions.

💡 Suggested Fix

In the SidebarControl_ItemDropped method, acquire a deferral from the event arguments before the await call and complete it after the operation is finished. Example: var deferral = e.RawEvent.GetDeferral(); await SidebarAdaptiveViewModel.HandleItemDroppedAsync(e); deferral.Complete();

🤖 Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent.
Verify if this is a real issue. If it is, propose a fix; if not, explain why it's not
valid.

Location: src/Files.App/Views/MainPage.xaml.cs#L482-L485

Potential issue: The `SidebarControl_ItemDropped` event handler is an `async` method
that performs significant asynchronous work, such as file operations and database
updates, via `SidebarAdaptiveViewModel.HandleItemDroppedAsync`. However, it fails to
acquire a deferral from the `ItemDroppedEventArgs`. In the WinUI drag-and-drop API, a
deferral is necessary to prevent the operating system from cleaning up the drag
operation's data context before the asynchronous work completes. Without it, the
`DataPackageView` could be invalidated mid-operation, leading to failed drop actions.

_{Did we get this right? 👍 / 👎 to inform future reviews.
Reference ID: 7750491}

[0x5bfa]

I moved this code from here, where there is no deferral code.

[marcelwgn]

I would argue its a bug that we didnt do that before then (though its unlikely) it might cause an issue, since we have no idea what might be done in the event handler.

[marcelwgn]

Put differently, we should use a deferral here.

[marcelwgn]

Why didnt we already remove this as part of #15594?
Why did we even need add the MenuItems property for that fix if we just bound to the same thing at the end of the day?

[0x5bfa]

This was used also in the SidebarView's automation peer class (which I changed in this PR).
I don't remember but no reason to delete it in that PR.

[marcelwgn]

In that PR all of those should have switched away from that property, having two truths which elements we present is really strange. Regardless, I guess we get rid of it now.