添加Firebase时，Unity项目无法在VS2015中编译

Question

I'm having troubles integrating Firebase for Unity in my project. As soon as I add it, it seems to work fine in Unity but the C# project does not compile anymore in VisualStudio 2015

I'm having a lot of warnings looking like :

>C:\Program Files (x86)\MSBuild\14.0\bin\Microsoft.Common.CurrentVersion.targets(1820,5):
warning MSB3258: The primary reference "Firebase.App" could not be resolved because it has  
an indirect dependency on the .NET Framework assembly "System, Version=4.0.0.0,  
Culture=neutral, PublicKeyToken=b77a5c561934e089" which has a higher version "4.0.0.0"  
than the version"2.0.0.0" in the current target framework.

Which, I assume are problematic because after a douzain of those on different classes from Google Firebase sdk for Unity I get :

[Edited Path of my project]\Assets\Firebase\Editor\AnalyticsDeps.cs(30,36,30,42): 
error CS0103: The name 'Google' does not exist in the current context

It seems that when building a version for Android, everything is fine but calls to LogEvent are not executed. Plus, with this problem I can no longer debug the scripts as they do not compile in VS.

Looks like it's .NET framework problem, but I have no idea how to solve this. I do not have latest version of Unity as I'm releasing very soon and I kept the last stable version (5.3.5f1) for my game (further versions made my game enter infinite loops)

[Edit] Here are the steps I used to reproduce the problem with a new Unity project having only one (default generated) script file:

Steps:

1. Have unity VS install so scripts are edited in Visual Studio 2015
2. Open existing project or create a new one in Unity with at least one script in the project
3. Add the .json for the app generated from the Google Developer console
4. Import FirebaseAnalytics.unitypackage into projects
5. Wait for all the unitypackage to process
6. Switch build setting to android if you're not already on Android platform
7. Assets -> Open C# project
8. Compile in VS
9. See all the MS Build warnings and following the error about google not being found

And here are the configs I tried it on :

Configuration : windows 7 home premium SP1 64bits with:

• VS 2015 community Version 14.0.25425.01 Update 3
• Unity Version 5.3.5f1 (960ebf59018a) Personal
• Android SDK Tools 25.2.3
• Android SDK Plateform-Tools 25.0.1
• Android SDK Build-Tools 25.0.1
• NDK 10
• JDK 8u111x64
• Firebase for Unity 1.0.1

I also did a clean install on another PC with latest Unity and VS 2015 and SDK/JDK/NDK etc. setup on a Windows 8.1 home edition with the same result. [/Edit]

Answer 1

Looks like a known issue, here is an answer from google support :

Hi Chris,

Thanks for sending all these details.

This is a legit issue and we are tracking this internally.

However, won't be able to commit about the ETA and timelines for this issue to get resolved.

In the meantime, the engineer of concerned team have suggested workaround to build in Unity (which you already did successfully) and go ahead with the release.

Regards,

Update:

Hello Chris,

Thanks for all the inputs and feedback to drive this bug to resolution.

We have fixed this bug in our Unity plugin.

This will be released and pushed soon to production. Keep an eye on our release notes .

Feel free to reach out if you have any further questions.

Regards,

Update 2 Fixed in version 1.1.0 of Firebase