Xcode Configuration Files

What Xcode configuration (.xcconfig) files are, and why they might be useful to you.

Presented at the HelsinkiOS/CocoaHeads meetup on January 22, 2013.

Transcript

1. Xcode configuration files
   Ali Rantakari
   HelsinkiOS / CocoaHeads • January 22, 2013
   

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2. Build Settings GUI
   

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3. [.xcconfig alloc]
   

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4. GUI vs Text
   GCC_PREPROCESSOR_DEFINITIONS = DEBUG=1 $(inherited)
   

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5. Unique pros
   Human readable names
   Comments
   Custom organization
   Better at avoiding repetition
   Discoverability
   

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6. Comments
   // I am disabling -Wunused-variable because goddamnit, I might
   // need those variables later! Who knows, right!
   //
   WARNING_CFLAGS = -Wall -Wno-unused-variable
   

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7. DRY to the max
   *_Common
   *_Debug *_Release
   #include
   #include
   

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8. DRY to the max
   LIBFOO_ROOT = $(SRCROOT)/MyApp/libfoo
   HEADER_SEARCH_PATHS = "$(LIBFOO_ROOT)/include"
   LIBRARY_SEARCH_PATHS = "$(LIBFOO_ROOT)/lib"
   (Yes, you can do this with the GUI as well, but this is nicer, no?)
   

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9. Inheritance
   WARNING_CFLAGS = -Wall
   Common.xcconfig
   #include "Common.xcconfig"
   WARNING_CFLAGS = $(inherited) -Wno-unused-variables
   Other.xcconfig
   (!!) does not do what you may think it does
   

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10. Inheritance
    WARNING_CFLAGS = $(inherited)
    App_Target_Debug.xcconfig
    inheritance
    project
    config
    target
    config
    Value of WARNING_CFLAGS in the project
    config
    

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11. If you must composite values…
    MY_COMMON_WARNING_CFLAGS = -Wall
    Common.xcconfig
    #include "Common.xcconfig"
    WARNING_CFLAGS = $(MY_COMMON_WARNING_CFLAGS) -Wno-unused-variables
    Other.xcconfig
    Set final composite value in “leaf” config
    file
    Use custom keys for intermediate values
    

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12. Resolved values
    = “first from the left”
    

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13. Demo
    

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