安装Xamarin.GooglePlayServices.Base NuGet后Xamarin.Android构建失败（XA4212错误）

Hey there, I’ve hit this exact XA4212 error a few times when dealing with mismatched Xamarin.Android library versions—let’s walk through how to resolve it:

Why This Happens #

The error error XA4212: Type Android.Support.V4.App.JobIntentService/JobServiceEngineImpl implements Android.Runtime.IJavaObject but does not inherit Java.Lang.Object or Java.Lang.Throwable pops up because of version conflicts between Google Play Services packages and Android Support Libraries (or AndroidX libraries, if you’ve migrated). Xamarin’s JNI binding rules require any type implementing IJavaObject to inherit from Java.Lang.Object or Throwable, and mismatched library versions break this binding logic.

Step-by-Step Fixes #

• Align all related NuGet package versions
  This is the most common fix. Ensure every Xamarin.GooglePlayServices.* package and Xamarin.Android.Support.* (or Xamarin.AndroidX.*) package in your solution uses a compatible version. For example:

  • If you’re on Xamarin.GooglePlayServices.Base v118.x, your Support libraries should be v28.x (the final stable Support library version)
  • If you’ve migrated to AndroidX, match Play Services versions to their corresponding AndroidX counterparts
    Use the Manage NuGet Packages for Solution window to check all project references—sort by package name to spot version mismatches easily, then update them to a unified compatible set.

• Clean and rebuild from scratch
  Old build cache can cause weird binding issues even after fixing versions. Do this:

  1. Go to Build > Clean Solution
  2. Manually delete the bin and obj folders from all your project directories
  3. Rebuild the solution

• Check for duplicate library references
  Sometimes third-party NuGet packages sneak in conflicting versions of Support/Play Services. Use the NuGet package manager to scan all projects for duplicate references (e.g., two different versions of Xamarin.Android.Support.v4), then remove the older or incompatible ones.

• Migrate to AndroidX (if you haven’t already)
  Google has deprecated the old Android Support Libraries, so migrating to AndroidX eliminates a lot of version compatibility headaches long-term. Xamarin has a built-in tool for this:

  1. Right-click your Xamarin.Android project in Solution Explorer
  2. Select Migrate to AndroidX...
     Note: Back up your project first—while the tool handles most cases, you might need to adjust some code references post-migration.

内容的提问来源于stack exchange，提问作者user2074945