Swift class using Objective-C class using Swift class

Question

I have an obj-c project to which I successfully added a new Swift class A, which is being used by some existing obj-c class B - the use of the automatically generated \"MyPr

Answer 1

This is a typical cyclical referencing problem.

Be careful to read the docs:

To avoid cyclical references, don’t import Swift into an Objective-C header file. Instead, you can forward declare a Swift class to use it in an Objective-C header. Note that you cannot subclass a Swift class in Objective-C.

So, you should use "forward declare" in .h, and #import in .m:

//  ObjCClass.h
#import <Foundation/Foundation.h>

@class SwiftClassA;

@interface ObjCClass : NSObject
@property (nonatomic, strong) SwiftClassA *aProperty;
@property (nonatomic) int *aNumber;
@end

// ObjCClass.m
#import "ObjCClass.h"
#import "MyProject-Swift.h"

@implementation ObjCClass
// your code
@end