bridging swift and objective-c

1
votes

I have objective-c project and I added swift files in it. i created bridge file and imported swift file in some header files without problems.

But I need to import some header files to swift files by adding them in the "<project-name>-Bridging-Header.h" file.

If I put header file in that bridge file and this header file was import swift file before; Xcode give me error message: "file not found" for the swift bridge file.

i.e:

  • I have project name called: "ProjectBlaBla"

  • I have header file called "readingPage.h"

  • I have swift file called: "readingSwift.swift"

  • swift bridge file's name: "ProjectBlaBla-Swift.h"

  • I created header bridge file: "ProjectBlaBla-Bridging-Header.h"

  • I imported "ProjectBlaBla-Swift.h" in "readingPage.h" file without problem and used swift classes inside objective-c

  • when I import "readingPage.h" in the "ProjectBlaBla-Bridging-Header.h", I got error message in "readingPage.h" said: "ProjectBlaBla-Swift.h file not found"

    any suggestions ?

thanks

3
iosobjective-cswift

3 Answers

3
votes

You are not able to reference -Swift.h files directly or indirectly in -Bridging-Header.h files.

If you open -Swift.h, you will see a line near the top, in my case line 99: #import "/Users/.../...-Bridging-Header.h", meaning -Swift.h already imports -Bridging-Header.h, so importing back creates a circular dependency.

To avoid this, any header you import in -Bridging-Header.h must use forward references to Swift classes or protocols it uses as described in answers to this question.

In short, if readingPage.h uses a Swift class named MySwiftClass you should:

  1. Remove any references to -Swift.h from readingPage.h.
  2. Import -Swift.h in readingPage.m
  3. Insert @class MySwiftClass; into readingPage.h before the class is used, letting Objective-C know that such a class exists and is declared elsewhere.
1
votes

Check whether the bridging header path is correct. On the left, select your project name -> TARGETS -> Build Settings -> search for Objective-C Bridging Header. Refer the photo below.

Bridging Header

0
votes

Two options

  1. Import the "ProjectBlaBla-Swift.h" inside the "readingPage.m" file instead of "readingPage.h" file
  2. Create a new PCH file named "Prefix.pch" and import "ProjectBlaBla-Swift.h" inside the "Prefix.pch" file.

Note: Prefix.pch is a precompiled header which makes compiling faster. You do not need to reimport any files that are imported in prefix.ch file.