What is an XCConfig file

Simply put, xcConfig is a configuration file that Apple uses in Xcode files to enable the same set of code to compile and run under different conditions

How to generate and configure a configuration file

  • 1. Add a new file to the project, select the configuration file template, and name it

  • 2. Configure the newly added file in project configuration1-nAn environmentxcconfigfile

  • 3. Now you can happily develop with a variety of configurations

xcconfigFile Syntax introduction

  • Xcconfig has a simple key-value pairing syntax, as follows
BUILD_SETTING_NAME = value
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  • annotation

Xcconfig supports only one comment \\

  • Use #include to import additional Settings

    • xcconfigFiles can be created multiple times and can be created inxcconfigAccording to the demand, will be otherxcconfigImport the configuration to this file through#includeThe corresponding xcconfig file path on keyword + will do

    1. Absolute paths can be added

       #include "/Users/someone/testxcConfig/testxcConfig/testxcConfig.Debug.xcconfig"
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2. Support relative path, which is actually the file path after ${SRCROOT} path link

 #include "testxcConfig/testxcConfig.Debug.xcconfig"
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variable

Variable definition, named according to OC, consists of uppercase letters, digits, and underscores only, uppercase in principle, but can also be lowercase; The string can be “or”; There are three special cases of variables:

1. InxcconfigDefined variables andBuild SettingIf the variables are the same, then the overwrite situation will occur and can be passed$(inherited)Keyword inheritanceBuild Setting, for example:

OTHER_LDFLAGS = -framework SDWebImage OTHER_LDFLAGS = $(inherited) - Framework AFNetworking // OTHER_LDFLAGS = -framework SDWebImage -framework AFNetworkingCopy the code

Note: Some variables cannot be configured to Build Settings through xcConfig. For example, PRODUCT_BUNDLE_IDENTIFIER does not work

2. Reference variablesThe ${}andRMB ()Can be

 VALUE=OC
 LANAUAGE=$(VALUE)-${VALUE}
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The conditional variable, according toSDK.ArchandConfigrationCondition the Settings

// Set 'Configration' to 'Debug' // Set 'SDK' to 'simulator', 'iphoneOS *' or 'MacOSX *' // Set the valid architecture to 'x86_64' OTHER_LDFLAGS[config=Debug][sdk=iphonesimulator*[arch=x86_64]= $(inherited) -framework "Demo"Copy the code

Note: In Xcode 11.4 and later, you can know default to specify the default value if the variable is null

$(BUILD_SETTING_NAME:default=value)
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The priority is from high to low

1. Manually configure Target Build Settings

2. The xcconfig file configured in Target

3. Manually configure roject Build Settings

4. Xcconfig file configured in Project