Objective C to Swift header file with multiple targets

Question

I'm successfully calling my Swift classes from Objective C (for target 'MyApp') via the import statement:

#import "MyApp-Swift.h"

I've now created a new target called "MyAppLite"

When I compile the new target, I get errors because "MyApp-Swift.h" is required by the code, but the compiler is creating "MyAppLite-Swift.h"

So, I need to create a conditional Swift/ObjC header #import for the target I'm compiling against.

How can this be done, or is there a better way?

user2067021 · Accepted Answer · 2016-07-07 01:03:43Z

98

It is also possible to set the Product Module Name setting in Build Settings to be the same across your modules (I set it to $(PROJECT_NAME)), so that the <project>-Swift.h file that is generated has the same name across all modules. This eliminates the need for adding/checking preprocessor macros.

edited Jul 7, 2016 at 1:03

user2067021

4,54940 silver badges45 bronze badges

answered Dec 10, 2014 at 21:43

C0D3LIC1OU5

8,6802 gold badges41 silver badges49 bronze badges

Sign up to request clarification or add additional context in comments.

7 Comments

Kevin R Over a year ago

When you create your first Swift-file in your project, xcode will ask you to add the bridging header to the project. In my case it only added the needed config to the first build target. So I also needed to fix the other build targets by configuring the Objective-C Bridging Header

Saltymule Over a year ago

I found that this caused issues in the build process, and that when switching between them, I needed to clean the build folder. I believe that because they all share the same project name, they all build to the same folder.

Dan Rosenstark Over a year ago

I"m not sure, but my feeling is that messing with the Product Module Name will affect something later on, probably when submitting to the App Store ;)... changing the Objective-C Generated Interface Header Name as described in the other answer has no implications.

C0D3LIC1OU5 Over a year ago

@Yar Just saw your comment. That was my feeling initially but the app has been in the App Store for a while and it hasn't been an issue. But if I was using the latest version of Xcode, I'd use Mike Fay's solution tbh. This answer was made before SWIFT_MODULE_NAME was available.

Vitalii Gozhenko Over a year ago

God bless you! Using same module name across all my targets save me from crappy issue with custom swift class in mixed Swift/ObjC project which happens only in release build!!! Thanks a lot!

|

Mike Fay · Accepted Answer · 2015-07-10 19:26:17Z

69

The best way I've found to address this issue is in your Xcode shared project settings. You can search for the following setting:

Objective-C Generated Interface Header Name*

If you set that value to a common header name, such as "MyProject-Swift.h", it will be applied to each of your targets and you can safely use the import declaration in any of your Objective-C files. This allows you to continue using unique product module names for each target, if needed.

I've tested this in Xcode Version 6.4 (6E35b).

*Note: This will appear under your Swift compiler settings, which are only visible if you have Swift source files added to your project. Additionally, if a target doesn't have any Swift source associated with it, the Swift compiler options will not be visible for that target's build settings.

Good luck!

edited Jul 10, 2015 at 19:26

answered Jul 10, 2015 at 19:15

Mike Fay

8766 silver badges8 bronze badges

7 Comments

Rafael Nobre Over a year ago

This is the best solution IMO.

Dan Rosenstark Over a year ago

The original value of this is $(SWIFT_MODULE_NAME)-Swift.h... so while this answer is awesome, I'd love to know how to adjust the SWIFT_MODULE_NAME for the module.

Dan Rosenstark Over a year ago

While I'm here, I'd recommend using some obvious name to reduce confusion, e.g., MidiDesignerAllTargets-Swift.h Thanks for this great answer, it's a great find.

hdoria Over a year ago

This is the best solution if you are using Xcode 7+.

Mike Fay Over a year ago

It is definitely still available in Version 8.3.3 (8E3004b).

|

Dmitry Isaev · Accepted Answer · 2017-01-09 08:28:59Z

54

Previous answers have some problems if you decide to rename your targets or project, or use SWIFT_MODULE_NAME as intended.

The most universal solution is to change SWIFT_OBJC_INTERFACE_HEADER_NAME (“Objective-C Generated Interface Header Name”) under Project's, not Targets, Build Settings, to:

$(PROJECT_NAME)-Swift.h — one per project;
$(SWIFT_MODULE_NAME)-Swift.h — one per module (default value).

answered Jan 9, 2017 at 8:28

Dmitry Isaev

4,0082 gold badges40 silver badges51 bronze badges

4 Comments

Klajd Deda Over a year ago

the cleanest of all solutions.Xcode 8.3.3, Swift 3, make sure the common/shared swift files belong to each target, all works after this.

ViruMax Over a year ago

How to handle "$(PROJECT_NAME)-Swift.h file not found" error like warnings?

Sandeep Rana Over a year ago

This should be accepted Answer as it shows some more details though @C0D3LIC1OU5 's answer was good enought

Emre Önder Over a year ago

This is what I'm looking for. Thank you for your answer.

Fittoburst · Accepted Answer · 2014-10-13 15:35:08Z

5

Well, the only way I can fix is to...

#ifdef IS_LITE
#import "MyApp_Lite-Swift.h"
#else
#import "MyApp-Swift.h"
#endif

Note that if there's any 'illegal' chars in my Product Module Name, they need to be replaced with underscores.

Hope that helps!

answered Oct 13, 2014 at 15:35

Fittoburst

2,3152 gold badges21 silver badges33 bronze badges

2 Comments

Saltymule Over a year ago

This worked for me, as the accepted answer caused build issues when switching between targets.

Duyen Hang Kim Over a year ago

what's IS_LITE?

Will · Accepted Answer · 2015-08-25 16:23:03Z

5

I put the appropriate #import <project>-Swift.h statement in a prefix header file (<project>-Prefix.pch) defined/added for each build (target/scheme).

answered Aug 25, 2015 at 16:23

Will

511 silver badge1 bronze badge

1 Comment

paulmelnikow Over a year ago

This has the advantage of making it more convenient to use Swift classes in Objective-C, and more consistency between the Swift experience, where headers do not need to be explicitly imported, and the Objective-C experience.

RGB_DS · Accepted Answer · 2021-03-10 08:35:31Z

1

pickture will tell you all

second targets name xxx and xxx-ih

select first target tap build setting -> find Objective-C Bridging Header set xxx-bridging-Header.h and Objective-C Generated Interface Header Name set xxx-Swift.h
select second target and same step 2

answered Mar 10, 2021 at 8:35

RGB_DS

1184 bronze badges

Comments

dvlprliu · Accepted Answer · 2024-09-03 04:28:39Z

1

Also check SWIFT_INSTALL_OBJC_HEADER to be YES under "Swift Compiler - General". It's default value should be YES, bug it's NO by default. 🤷

answered Sep 3, 2024 at 4:28

dvlprliu

342 bronze badges

1 Comment

Yonic Surny Jul 25 at 18:42

This is what was missing for me, thanks

Ahmad Albash · Accepted Answer · 2017-01-18 11:27:32Z

0

The only working way is the following :

1- from first target (which has a working bridging) Build Setting select Objective C Bridging Header
2- Copy Objective C Bridging Header
3- open the other target Build Setting
4- Paste it 5- change the header file to your new header file (i.e target B.h)

(now you have this option for two target)

answered Jan 18, 2017 at 11:27

Ahmad Albash

11 bronze badge

Collectives™ on Stack Overflow

Objective C to Swift header file with multiple targets

8 Answers 8

7 Comments

7 Comments

4 Comments

2 Comments

1 Comment

Comments

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

8 Answers 8

7 Comments

7 Comments

4 Comments

2 Comments

1 Comment

Comments

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related