Hey Xamarin.Forms gurus!
I needed a TreeView control for Xamarin.Forms and couldn't find one, so I did a spike and came up with a working prototype and demo app.
It its current version, data binding isn't set up, and the item template for the node header isn't separated out, but I think the demo provides a really good sense of the potential of this approach to building a TreeView as a set of nested StackLayouts (TreeNodeView inherits from StackLayout).
There's a screen image that I checked in with the source code, and I designed the layout of the demo for my 7" tablet, but it should squeeze down okay to smaller devices.
Here's the github repository:
https://github.com/danvanderboom/Xamarin-Forms-TreeView
KEY POINT: If you're familiar with best practices in building custom controls for Xamarin.Forms and you're interested in shaping the future of an open source TreeView control, let me know!