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iOS

Posted by kasaltrix
kasaltrix
9,491 Points

Confusion between Foundation and UIKit Frameworks

This question might sound silly because I am a beginner in iOS Development.

I wanted to ask that how can we use the classes found in the Foundation framework such as NSArray or NSString within an iOS project file even though we do not import Foundation/Foundation.h anywhere in our project.

On the other hand if I make a custom class in an iOS project inheriting from the NSObject using the File>NewFile option and want to use a UIKit Framework class, I have to import the UIKit/UIKit.h header file in that given project file.

1 Answer

Dylan Shine
Dylan Shine
17,565 Points
Dylan Shine
Dylan Shine
17,565 Points

I believe when you create a new Cocoa Touch Class, Foundation is imported in the background by default. UIKit on the other hand isn't used to build all projects, such as command line applications, so they require you to import it manually on files that don't. If I create a new Cocoa Touch Class that inherits from NSObjects, I won't get UIKit, but if it inherits from something like UIViewController than it will...Xcode is just smart in that way.

kasaltrix
kasaltrix
9,491 Points

Thanks for your reply Dylan.

I googled some answers for my question and found that the .pch file was responsible for importing both these frameworks. But those articles were pretty outdated and I cannot find the .pch file under the supporting files folder in my iOS project.
I presume that what you are saying is correct but I am still confused!