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 for Bug 60447 on
Developer Community if you have new
information to add and do not yet see a matching new report.
If the latest results still closely match this report, you can use the
Created attachment 25508 [details]
Custom Layer and View animation that shows use of Layer
In a workbook, create a custom layer and custom view. In the ActionForKey override, access the UIView.Layer.PresentationLayer.CornerRadius property. Now, do the same in a solution. And then access the subtly shorter UIView.Layer.CornerRadius property.
It's complicated. The PresentationLayer is a copy of the View's layer for information and calculation. Assigning to it is allowed, but has no effect, on iOS. Assigning UIView.Layer.CornerRadius is the way implicit animations are created (with other finagling.)
In a solution running on iOS, NullReferenceException on the PresentationLayer if the view has not been displayed. Otherwise, in a solution, success and a no-op. In a workbook, success, and the animation happens (with the finagling mentioned above).
The desired behavior for the workbook is, since the view has been displayed, that the assignment not throw an exception, but have no result. The user should be required to assign to UIView.Layer.CornerRadius, and/or UIView.CornerRadius.
The attached solution is patterned after Erica Sadun's implicit animation blog post. (http://www.informit.com/articles/article.aspx?p=2233980) I will be attaching a similarly patterned workbook that has the incorrect behavior, shortly.
Created attachment 25509 [details]
Workbook showing PresentationLayer assignment bug
The assignment to PresentationLayer.CornerRadius should succeed, but not cause animation. In reality, it succeeds and acts as if it were an assignment to Layer.CornerRadius, triggering the animation.