Created attachment 12650 [details]
When setting the preferred language to "Chinese, Traditional", I would expect that the CurrentCulture and CurrentUICulture properties would be set to "zh-Hant" or "zh-TW". Instead, they are always set to "zh-CN".
This makes it difficult to use traditional Chinese localizations from a Resources.zh-TW.resx or Resources.zh-Hant.resx file.
See the attached Xamarin.iOS sample project that exhibits the behavior.
1. Open the iPad simulator
2. Set the preferred Language to "Chinese, Traditional"
3. Run the attached Xamarin.iOS project.
CurrentUICulture and CurrentCulture should be set to Chinese (Traditional), not Chinese (Simplified)
Created attachment 12651 [details]
Test app screenshot on iPhone 4S iOS 8.4 simulator
In the uploaded screenshot the region code was still set to United States.
Setting the region code to "China" makes no difference in the output of the managed code, other than properly setting the NSLocale to "zh-Hant_CN"
This appears to do what is expected if the region is set to TW as well as setting the Language to "Chinese, Traditional"
I'm not convinced there's actually a bug here. I don't actually know how common it might be to have a user set the Region to China and expect Chinese Traditional. I guess seeing what .NET 4.5 or 4.6 does would probably be a better validation of what this *should* do.
Fixed in master and mono 4.2 branch