Using iOS Objective-C SDK classes

Just as we saw regarding Android in the previous recipe, Delphi is able to access the iOS SDK as well. In this section, we'll talk about the mechanisms that the compiler offers to import classes from the iOS SDK. This is not a standard recipe, but more of a showcase showing the possibilities offered by the Delphi compiler and the process needed to fully use them when dealing with OS built-in libraries. The mechanism is similar to the Android ones, but there are some notable differences.

Getting ready

In Objective-C, all classes have NSObject as a common ancestor. The iOS SDK is composed of some frameworks. An iOS framework is a number of classes specialized for a single purpose. For example, UIKit is the framework containing all the basic classes related to the UI, the iAd framework contains all the stuff related to the advertising, and MapKit wraps up all the mapping-related classes.

Note that Objective-C uses the NSString objects, while Delphi uses strings...