iOS: Firebase Analytics Fails to Send Custom Events with Adjust Integration

Below is an explanation and recommendations on how to resolve the issue:

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What’s Happening

The log message

objc[22132]: Class FIRAnalytics is implemented in both ... One of the two will be used. Which one is undefined.

indicates that the Firebase Analytics class is being included twice – once in your main binary (OceanMatchWorld) and once in the UnityFramework framework. This duplication can lead to unpredictable behavior, such as custom events not being delivered as expected.

A likely contributor is the mix of Firebase pods you’re including. In your Podfile you have both:

• pod 'Firebase/Analytics'
• pod 'Firebase/Core'

Firebase/Core traditionally brought in Analytics among other things. However, Firebase has moved to using Firebase/Analytics explicitly, and mixing these pods can cause Firebase to be configured twice.

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Recommendations

1. Remove Duplicate/Deprecated Pods
   Since Firebase/Core is no longer required if you are using Firebase/Analytics, remove Firebase/Core from your Podfile. This will avoid loading the Firebase Analytics implementations twice.

2. Check Your Target Configuration
   Ensure that Firebase isn’t being initialized more than once. If the Firebase SDK is already brought in by one target (or binary), avoid including it a second time in a dependency or framework that is loaded into the same process.

3. Verify Custom Event Logging Implementation
   Once the duplicates are removed and Firebase is initialized only once (typically in your app delegate), make sure your custom event logging uses the proper API call such as:

   SWIFTCopied
   Analytics.logEvent("your_custom_event", parameters: [
     "key": "value"
   ])

   This will ensure that Analytics records your events.

4. Re-run CocoaPods Installation
   After updating your Podfile, run:

   BASHCopied
   pod install

   and rebuild your project so that the changes take effect.

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Example Updated Podfile

Below is an example of how you might update your Podfile by removing Firebase/Core:

RUBYCopied
source 'https://cdn.cocoapods.org/'
source 'https://github.com/CocoaPods/Specs'

platform :ios, '13.0'

target 'UnityFramework' do
  pod 'Adjust', '5.0.1'
  pod 'FBSDKCoreKit', '~> 17.0.1'
  pod 'FBSDKCoreKit_Basics', '~> 17.0.1'
  pod 'FBSDKGamingServicesKit', '~> 17.0.1'
  pod 'FBSDKLoginKit', '~> 17.0.1'
  pod 'FBSDKShareKit', '~> 17.0.1'
  pod 'Firebase/Analytics', '11.6.0'
  pod 'Firebase/Auth', '11.6.0'
  # Removed the following line because it’s no longer needed:
  # pod 'Firebase/Core', '11.6.0'
  pod 'Firebase/Crashlytics', '11.6.0'
  pod 'Firebase/Messaging', '11.6.0'
  pod 'Firebase/RemoteConfig', '11.6.0'
  pod 'Google-Mobile-Ads-SDK', '~> 11.13.0'
  pod 'GoogleSignIn', '>= 4.0.2'
  pod 'GoogleUserMessagingPlatform', '2.7.0'
end

target 'Unity-iPhone' do
end

use_frameworks!

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Final Note

By removing the redundancy in the inclusion of Firebase libraries and ensuring that Firebase is initialized only once, your custom events logging should work as expected even when Firebase and Adjust are used together.