Xamarin.Auth AccountStore.Save模拟器正常，真机运行报错求助

Hey there, let's work through this issue where your AccountStore.Save() method throws an exception on physical devices via Xamarin Live Player, but works perfectly in the Visual Studio simulator.

The Root Cause #

Xamarin Live Player runs your app in a restricted, sandboxed environment that doesn't support all native platform APIs. AccountStore relies on platform-specific secure storage systems (like iOS Keychain or Android Keystore) to persist credentials, and these system-level APIs are often blocked or unavailable in the Live Player context. That's why you're seeing the "missing method" or runtime exception—Live Player can't access the underlying native code needed to save the account data.

Solutions to Try #

• Switch to direct USB debugging on your physical device
  This is the most reliable fix. Xamarin Live Player is great for quick UI testing, but it's not built for accessing sensitive system APIs like secure storage. Connect your device via USB, enable developer options/USB debugging on the device, then select your physical device as the run target in Visual Studio. Deploying directly to the device will give your app full access to the native secure storage APIs, so AccountStore.Save() should work as expected.

• Verify platform-specific configurations (for direct debugging)
  If you still run into issues after switching to direct debugging:

  • For Android: Ensure your project targets a supported Android version (AccountStore works best with API 23+), and there are no conflicting permissions or security configurations in your AndroidManifest.xml.
  • For iOS: Make sure your app's entitlements include necessary Keychain access (though Xamarin.AccountStore usually handles this automatically for basic use cases).

• Temporary workaround for Live Player testing (not for production)
  If you absolutely need to test the credential flow in Live Player, you can use a temporary, less secure storage option like Xamarin.Essentials.Preferences to store dummy credentials during testing. Just remember to replace this with AccountStore once you move to direct device debugging:

  // Temporary workaround for Live Player testing only
  Preferences.Set("Username", yourUsername);
  Preferences.Set("Password", yourPassword);
  

  Note: Never use Preferences for storing sensitive production data—it's not encrypted.

内容的提问来源于stack exchange，提问作者bpatterson