Android Google SignIn getCredentialAsync方法参数报错及解决

问题背景 #

实现Android Google登录功能时，在app模块的build.gradle中引入以下依赖：

implementation "androidx.credentials:credentials:1.3.0"
implementation "androidx.credentials:credentials-play-services-auth:1.3.0"
implementation "com.google.android.libraries.identity.googleid:googleid:1.1.1"

在MainActivity.java中编写startGoogleLogin方法，当判断SDK版本≥Android 14（UpsideDownCake）时，创建CredentialManager实例并构建GetCredentialRequest，调用getCredentialAsync方法时出现方法不可识别的报错。即使确认参数类型与方法签名完全匹配，问题仍未解决，最终通过将CancellationSignal参数设为null解决了问题。

修正后的完整代码 #

import androidx.core.os.CancellationSignal;
import androidx.credentials.Credential;
import androidx.credentials.CredentialManager;
import androidx.credentials.CredentialManagerCallback;
import androidx.credentials.CustomCredential;
import androidx.credentials.GetCredentialRequest;
import androidx.credentials.GetCredentialResponse;
import androidx.credentials.PasswordCredential;
import androidx.credentials.PublicKeyCredential;
import androidx.credentials.exceptions.GetCredentialException;
import com.google.android.libraries.identity.googleid.GetGoogleIdOption;
import com.google.android.libraries.identity.googleid.GoogleIdTokenCredential;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import java.security.SecureRandom;
import android.content.Context;
import android.util.Log;

public void startGoogleLogin() {
    String serverClientId = ""; // 替换为你的服务器客户端ID

    // 生成Nonce用于安全验证
    SecureRandom secureRandom = new SecureRandom();
    byte[] randomBytes = new byte[24]; // 24字节=192位
    secureRandom.nextBytes(randomBytes);
    String nonce = java.util.Base64.getUrlEncoder().withoutPadding().encodeToString(randomBytes);

    // 构建Google登录选项
    GetGoogleIdOption googleIdOption = new GetGoogleIdOption.Builder()
            .setFilterByAuthorizedAccounts(false)
            .setServerClientId(serverClientId)
            .setAutoSelectEnabled(true)
            .setNonce(nonce)
            .build();

    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.UPSIDE_DOWN_CAKE) {
        CredentialManager credentialManager = CredentialManager.create(this);
        Context context = getApplicationContext();
        GetCredentialRequest request = new GetCredentialRequest.Builder()
                .addCredentialOption(googleIdOption)
                .build();
        
        Executor executor = Executors.newSingleThreadExecutor();
        CredentialManagerCallback<GetCredentialResponse, GetCredentialException> callback = 
            new CredentialManagerCallback<GetCredentialResponse, GetCredentialException>() {
                @Override
                public void onResult(GetCredentialResponse result) {
                    Log.v(TAG, "获取凭证成功: " + result.getCredential().toString());
                }

                @Override
                public void onError(GetCredentialException e) {
                    Log.v(TAG, "获取凭证失败: " + e.toString());
                }
            };

        try {
            // 将CancellationSignal参数设为null解决方法不可识别问题
            credentialManager.getCredentialAsync(context, request, null, executor, callback);
        } catch (GetCredentialException e) {
            Log.v(TAG, "获取凭证异常: " + e.toString());
        }
    }
}

关键说明 #

• 原代码中创建CancellationSignal实例并传入方法是触发报错的原因，即便参数类型匹配，部分环境下仍会出现方法识别异常。
• 传入null作为CancellationSignal参数是官方允许的合法用法，不会影响功能正常运行，同时彻底解决了方法不可识别的报错。

内容的提问来源于stack exchange，提问作者John