About deprecated api and SDKs

About deprecated api and SDKs



UIAlertview is available from iOS 2.0 to iOS 9.0. From iOS 8.0 .XCode will warn that use UIAlertController instead.


But when i set base sdk as iOS 10.3 and set deployment target as iOS 7.1, the app will run from iOS 7.1 to iOS 10.3 devices succefully.


And when set base sdk as iOS 10.3 and set deployment target as iOS 10.0, the app also run successfully ,just have many waring ,but build successfully.