Xamarin生成APK失败：apksigner.BAT退出码2求助

Hey there, sorry to hear you're stuck with this frustrating error when building your Xamarin APK. Even though you're already on JDK 1.8.0_131 (which is compatible for most Xamarin scenarios), let's dig into some targeted fixes that might resolve the exit code 2 issue:

Common Fixes to Try #

• Verify apksigner availability and permissions

  • First, confirm the apksigner.bat file exists in your Android SDK build-tools directory (typically C:\Users\<YourUsername>\AppData\Local\Android\Sdk\build-tools\<your-build-tools-version>\). If it's missing, re-install the corresponding Build Tools version via the Android SDK Manager.
  • Try running Visual Studio as an administrator—permission restrictions can sometimes block apksigner from executing properly.

• Validate your signing configuration

  • Double-check your Android project's signing settings (right-click project → Properties → Android Options → Signing). Ensure the keystore path is correct, and that the keystore password, key alias, and key password are all accurate (typos here are a common culprit).
  • Test signing manually using the apksigner command to get more detailed error output. Open a command prompt, navigate to your build-tools folder, and run:

    apksigner sign --ks "C:\path\to\your\keystore.keystore" --ks-key-alias your-key-alias "C:\path\to\your\unsigned.apk"
    

    This will often reveal specific issues like a corrupted keystore or mismatched credentials that the VS build log doesn't show clearly.

• Clean and rebuild from scratch

  • Go to Build → Clean Solution in Visual Studio, then manually delete the bin and obj folders from your Android project directory.
  • Rebuild the solution—cached build artifacts can sometimes interfere with the signing process.

• Double-check environment variables

  • Confirm that JAVA_HOME is set to the root directory of your JDK 1.8.0_131 installation (not the JRE subfolder).
  • Check your Path environment variable to ensure no other JDK versions are listed before your 1.8.0_131 path—this can cause the system to use a conflicting Java version.
  • Verify the version by running java -version and javac -version in a command prompt; both should show 1.8.0_131.

• Switch Android Build Tools versions

  • Sometimes specific Build Tools versions have compatibility issues with apksigner. Try updating to a newer stable version (e.g., 30.0.3) or rolling back to a well-tested version like 28.0.3 via the Android SDK Manager, then rebuild your project.

If none of these steps resolve the issue, sharing the full, detailed error log (beyond just the "Build Failed" message) and redacted details of your signing configuration (omit passwords) would help narrow down the problem further.

内容的提问来源于stack exchange，提问作者Jen143