Call Swift Code From Objective-C Code

Category: Swift

This TIL shows how to call Swift code from Objective-C code in the same project without creating a circular dependency.

Ensure the method you are trying to call in your Swift class is prefixed with @objc, for example:

public class YourSwiftClass: NSObject {
    
    @objc public func someMethod() {
        print("Hello world!")
    }
    
}

Add a forward reference in your Objective-C header file:

@class YourSwiftClass; // Forward reference to Swift class

@interface YourObjectiveC : NSObject
{
    YourSwiftClass* yourSwiftClass;
}

@end

In your Objective-C implementation file, call the Swift method:

#import "ProjectName-Swift.h"
#import "YourObjectiveC.h"

@implementation YourObjectiveC

// Implement methods or properties that use YourSwiftClass
[yourSwiftClass someMethod];

@end