Notice (2018-05-24): bugzilla.xamarin.com is now in
Please join us on
Visual Studio Developer Community and in the
Mono organizations on
GitHub to continue tracking issues. Bugzilla will remain
available for reference in read-only mode. We will continue to work
on open Bugzilla bugs, copy them to the new locations
as needed for follow-up, and add the new items under Related
Our sincere thanks to everyone who has contributed on this bug
tracker over the years. Thanks also for your understanding as we
make these adjustments and improvements for the future.
Please create a new report on
Developer Community or GitHub with
your current version information, steps to reproduce, and relevant error
messages or log files if you are hitting an issue that looks similar to
this resolved bug and you do not yet see a matching new report.
UIImageView.HighlightedImage = null throws an NRE, so there is no way to unset this value.
In objc highlightedImage = nil behaves as expected.
The [NullAllowed] attribute is present. OTOH when a binding is missing a [NullAllowed] it should be throwing an ANE (ArgumentNullException) not a NRE (NullReferenceException).
Which version of MonoTouch are you using ?
Oh, sorry, it is an ANE. MT version 6.0.8.
[ERROR] FATAL UNHANDLED EXCEPTION: System.ArgumentNullException: Argument cannot be null.
Parameter name: value
at MonoTouch.UIKit.UIImageView.set_HighlightedImage (MonoTouch.UIKit.UIImage value) [0x0000b] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIImageView.g.cs:239
It's fixed but it's not in 6.0.8 (or in 6.0.9) but it will be in 6.2 (and it's part of the 6.1 betas).
p.s. I can give you a workaround (manual binding) if this blocks you.