Use User-Defined build settings in custom .plist file

Question

I have different build configurations (Debug, Stage, Prod) defined for my app and I use User-Defined build settings:

to set up Facebook log

Answer 1

1. Create a new folder (for example: GoogleServiceInfoPlists).

2. Copy there all .plist files for each Configuration

for example:

GoogleService-Info-Debug.plist, 
GoogleService-Info-Alpha.plist,
GoogleService-Info-Beta.plist,
GoogleService-Info-Release.plist

3. Add new Run Script Phase at last (Xcode: Target -> Build Phases -> "+" button).

4. Use script below to copy .plist file for given environment to the build directory.

script:

RESOURCE_PATH=${SRCROOT}/${PRODUCT_NAME}/GoogleServiceInfoPlists/GoogleService-Info-$CONFIGURATION.plist

BUILD_APP_DIR=${BUILT_PRODUCTS_DIR}/${PRODUCT_NAME}.app

echo "Copying ${RESOURCE_PATH} to ${BUILD_APP_DIR}"
cp "${RESOURCE_PATH}" "${BUILD_APP_DIR}/GoogleService-Info.plist"

PS: You do not need to add the file to project. Just create a new folder in the main directory.