I implemented a PSRadioGroupSpecifier like so: 
1. Regardless of which value a user selects inside the radio button group, next time the settings are opened the default value is marked as selected. Imho this is a bug in iOS, as i figured out that the value of the settings property is correctly set and could be retrieved.
Question: How to come around the false display in settings app WITHOUT using PSMultiValueSpecifier?
来源：https://stackoverflow.com/questions/34389422/ios-settings-bundle-psradiogroupspecifier-does-not-show-selected-value