Not sure where to stick this, as not even sure why this isn't working (i.e. if it's Forms, or VS - which had been playing up right before I discovered this - or UWP, or...), so I'll stick this under General.
Working on something, things were just not working (for reasons that turned out to be nothing to do with my code, but it's led to a discovery),so I decided to delete and reclone. Having done that, I went through making sure everything was now working, only to find it wasn't. My single image display from an image search, which had previously been working (at this last commit), now wasn't. After some detective work, I eventually found that...
this (still) works - ResultsImage="https://developer.xamarin.com/demo/IMG_1415.jpg";
this doesn't - ResultsImage=imageResults.Value.ElementAt(0).ContentUrl; (but had been working previously)
note: imageResults is a Bing image search ImageObject. ResultsImage is a source string property which has been bound to an image in my view.
i.e. if I hardcode an image source in, it works, but if I try to load it from a variable it doesn't. I even tried adding a .tostring() at the end just to be doubly-sure, but that doesn't work either. I suspect an unfortunate co-incidence that this (whatever this is) broke just when I changed from loading single images to trying a ListView (so all this time I couldn't get ListView working, was actually that my images were no longer loading from a variable to begin with). BTW ContentUrl is definitely valid, as if I copy+paste it into a browser the image comes up. Just won't load within the app for some reason (well, the image from it isn't displaying anyhow).
So, anyone have any idea what is going on here and how to fix it?