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 59878 on
Developer Community or GitHub 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
In special cases on GitHub you might also want the comments:
GitHub Markdown with public comments
Using this custom renderer causes InvalidCastException inside the base class OnElementChanged function:
[assembly: ExportRenderer(typeof(NavigationPage), typeof(NavigationPageRenderer))]
public class NavigationPageRenderer : NavigationRenderer
protected override void OnElementChanged(ElementChangedEventArgs<NavigationPage> e)
It may or may not matter, but in my case, the NavigationPage in question is being used inside a MasterDetailPage Detail pane.
This bug appears to be documented elsewhere:
Ah... I figured out the problem.
It's AppCompat vs. regular. Which I had no idea was a thing until encountering this.
It would be really useful to have an informative exception message to direct developers to the correct classes.