Drag and drop does not work in a flyout with ShouldConstrainToRootBounds set to false

[benstevens48]

Drag and drop does not work in a flyout with ShouldContrainToRootBounds set to false. The DragOver and Drop events do not fire.

Windows 10 version	Saw the problem?
November 2019 Update (18363)	Yes

[codendone]

Yes, this is not supported with the current implementation of ShouldConstrainToRootBounds=false popups. Originally that support was only used for tooltips and MenuFlyout, neither of which should be a drop target (and should usually auto-hide before any potential drag-n-drop operation). With the expanded use and exposure of the ShouldConstrainToRootBounds property, this is a limitation which you could hit.

This isn't likely to be something we'll fix any time soon. I expect the implementation of ShouldConstrainToRootBounds will eventually be changed in WinUI, but not until sometime after 3.0. Hopefully setting ShouldConstrainToRootBounds=true is sufficient for you for now?

[benstevens48]

Yes, at the moment it's just a nice-to-have feature for me. But it's not a totally outrageous thing to try to do. Basically I'm using the flyout as a menu with a list of items, but the user can reorder the items, for which I'm using the drag-and-drop functionality as it's convenient. I could rewrite my code not to use drag and drop, but that would be a bit time consuming, especially writing an alternative for the dragging UI preview, so I'll just keep ShouldConstrainToRootBounds as true for now.

I have to say it's really great that ShouldConstrainToRootBounds was added. As a direct result of that, I've been able to add a rich context menu to my app which makes certain actions much quicker to get to. Luckily, I don't need the user to reorder these!

[codendone]

Thanks for logging this. The current thinking is that eventually we'd like to have ShouldConstrainToRootBounds=false popups use a XAML Island behind the scenes, at which point drag-n-drop should work as long as it works for islands.

Since we're not likely to get to this for a while, I'd like to close this. But we definitely should support this eventually.

[FireCubeStudios]

Hello I am need of drag and drop events to fire now with #9276 there are some usecases with flyouts to be drop targets