All about linking libraries

All about linking libraries - How to solve import/link errors-
- Anatomy of linking libraries or frameworks
- Anatomy: importing libraries or frameworks

Transcript

1. All about linking
   libraries
   How to solve import/link errors
   

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2. How do you use libraries or
   frameworks in Swift project?
   

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3. Dragging to Embedded Binaries
   

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4. Import frameworks without modules
   (Some ObjC vendored frameworks)
   

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5. Dynamic vs Static
   w/ Bundle vs wo/Bundle
   Static Library (*.a)
   Static Framework (*.framework)
   Dynamic Framework (*.framework)
   Dynamic Library (*.dylib)
   

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6. with Bundle without Bundle
   Static Linking
   Dynamic Linking
   Dynamic vs Static
   w/ Bundle vs wo/Bundle
   Static Library
   Static Framework
   Dynamic Library
   Dynamic Framework
   

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7. Anatomy of linking libraries or
   frameworks
   

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8. How to make available
   external frameworks/libraries in Swift
   • Import the framework/library from your app or framework
   
   • Link the framework/library to your app or framework
   

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9. How Swift import
   frameworks/libraries
   

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10. What need to import libraries into Swift?
    

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11. Module
    

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12. Frameworks can contain modules
    

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13. Some frameworks don't have modules
    

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14. Any Library doesn't have modules
    Static Library (*.a)
    Dynamic Library (*.dylib)
    

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15. Anatomy: importing
    libraries or frameworks
    

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16. How to import frameworks
    • Does the framework has modules?
    
    Yes:
    
    => Set parent directory of the framework to Framework Search Paths
    

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17. Set parent directory of the framework to
    Framework Search Paths
    

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18. How to import frameworks
    • Does the framework has modules?
    
    No:
    
    • Do you try to import the framework to your app?
    
    Yes:
    
    => a) Create module map.
    
    b) Create bridging header.
    
    No:
    
    => Create module map.
    

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19. a) Bridging Header
    

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20. a) Bridging Header
    

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21. a.) Bridging Header
    

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22. b) Module Map
    

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23. b) Module Map
    

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24. b) Module Map
    module Marketo {
    umbrella header "../../Frameworks/Marketo.framework/Headers/Marketo.h"
    export *
    module * { export * }
    }
    

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25. b.) Module Map
    

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26. Import libraries
    

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27. How to import libraries
    • a) Create bridging header.
    
    • b) Create module map.
    

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28. Import libraries
    

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29. a) Bridging Header
    

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30. b) Module Map
    module WebPDecoder {
    header "include/decode.h"
    header "include/types.h"
    }
    

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31. Anatomy: linking
    libraries or frameworks
    

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32. How to link frameworks
    • Is the framework dynamic framework?
    
    Yes:
    
    => Copy the framework into the app bundle
    
    => Set parent directory of the framework to Framework Search Paths
    
    => Set -framework to Other Linker Flags
    
    No:
    
    => Set parent directory of the framework to Framework Search Paths
    
    => Set -framework to Other Linker Flags
    e.g.) -framework KeychainAccess
    

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33. Link dynamic frameworks
    

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34. Copy frameworks into app bundles
    

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35. Link frameworks
    

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36. How to link libraries
    • Is the library dynamic library?
    
    Yes:
    
    => Set parent directory of the framework to Library Search Paths
    
    => Copy the library into the app bundle
    
    No:
    
    => Set parent directory of the framework to Library Search Paths
    
    => Set -l to Other Linker Flags
    e.g.) -lwebpdecoder
    

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37. Link libraries
    

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38. You might see...
    => Correct module map
    
    => Make sure Header Search Paths is correct
    
    

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39. Recap
    • The processes of making external libraries available in the Swift project.
    
    => Import and Linking
    
    • Errors on importing
    
    => Module maps, Framework/Library Search Paths, Import Paths
    
    • Errors on linking
    
    => Module maps, Framework/Library Search Paths, Static or Dynamic
    
    • Errors on runtime
    
    => "Copy Files" Build phase
    

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40. Resources
    • http://nsomar.com/modular-framework-creating-and-using-them/
    
    • https://theswiftdev.com/2018/01/25/deep-dive-into-swift-frameworks/
    
    • https://samsymons.com/blog/understanding-objective-c-modules/
    
    • http://clang.llvm.org/docs/Modules.html
    

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