如何使用外部文件.plist或.xcconfig启用部分代码

Question

I have a project that I'm using the fastlane toolchain to build.

I have multiple deployment targets (hockey app, test flight, app store) - and for each deployment I'm interested in disabling and enabling certain features.

For example - when i'm doing an alpha build with an enterprise cert to hockeyapp i want to disable flurry analytics.

When i'm doing a beta build I want to change the app-id and/or change the flurry key

I currently have everything working in fastlane with a variety of sed commands to search and replace files etc.

That being said, I'm sure there is a better way.

I know in Obj-c i can #ifdef against certain build environment flags to enable / disable parts of code. What is the best way to go about this in swift.

Do I use some sort of custom .plist file or .xcconfig setting to tell the app what to do/use or is there a different way?

The things i'm interested in are

• Disabling portions of code ( ignore a certain function in a specific config)
• Changing values used in code aka API_KEY or something like that

Answer 1

You can still use something similar to #ifdef preprocessor in swift, and you can combine it with .xcconfig which can be used to specify various variables. Your scripts can generate the values that will go into the .xcconfig vars.

The basic setup would be:

1. Create a .xcconfig file and associate it with your desired build configurations (in project settings -> info).
2. Add variables to the .xcconfig . For example, if you want to activate ALPHA build you can do something like this: IS_ALPHA_BUILD=-D ALPHA . Notice the -D which is necessary here. Your scripts can leave the variables empty if you want the flag turned off.
3. In the build settings for your target, under "Swift Complier - Custom Flags" - > "Other Swift Flags" add the flag based on the .xcconfig file variables: ${IS_ALPHA_BUILD} . If the .xcconfig is setup correctly you should see its content of the variable once you're done editing the variable.

4. Use the flags in your code:

    #if ALPHA print("alpha") #else print("not alpha") #endif 

I hope this helps, or that it will at least give you an idea for the best approach suitable for you.

Answer 2

I would suggest placing the optional code in separate files that implement it using extensions. You can then enable/disable files using the file properties in the project Navigator.

I'm doing this even for a single application for which I have 3 targets in the project : full IOS version (paid), limited IOS version (free) and apple TV version.

I also use the same technique to enable/disable stubs for whole classes that are used in several places but only actually work in one of the targets.

Answer 3

I have a similar conceptual problem. I want to use FDD and than use a mechanism to disable features as per need. I am going to experiment with pList. My initial idea is to declare all features in plist and give them boolean values. Thus, if a feature needs to be enabled, I will only enable it in plist.

On the programming side, I am planning to write all features as extensions for parent data type with enclosing conditional statements. Therefore from perspective of controller , my code efforts will be reduced to just calling the behavior/ function.

I hope it made some sense, I will probably rewrite the answer sooner than later