AWS Mobile Client showSingIn成功完成，但Cognito Userpool未登录

Question

我正在使用AWS Mobile客户端实施SSO。 showSignIn方法成功完成，用户状态已登录，但是随后当我对GraphQL进行任何请求时，它均失败，并显示错误“未登录Cognito用户池”。是什么原因造成的？我的意思是，SSO登录成功，但是GraphQL请求失败。

java.io.IOException: Failed to retrieve Cognito User Pools token.
    at com.amazonaws.mobileconnectors.appsync.sigv4.AppSyncSigV4SignerInterceptor.intercept(AppSyncSigV4SignerInterceptor.java:148)
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
    at com.amazonaws.mobileconnectors.appsync.retry.RetryInterceptor.intercept(RetryInterceptor.java:40)
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
    at okhttp3.logging.HttpLoggingInterceptor.intercept(HttpLoggingInterceptor.java:221)
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
    at okhttp3.RealCall.getResponseWithInterceptorChain(RealCall.java:264)
    at okhttp3.RealCall$AsyncCall.execute(RealCall.java:210)
    at okhttp3.internal.NamedRunnable.run(NamedRunnable.java:32) 
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636) 
    at java.lang.Thread.run(Thread.java:764) 
 Caused by: java.lang.RuntimeException: Cognito Userpools is not signed-in
    at com.amazonaws.mobileconnectors.appsync.sigv4.BasicCognitoUserPoolsAuthProvider.fetchToken(BasicCognitoUserPoolsAuthProvider.java:80)
    at com.amazonaws.mobileconnectors.appsync.sigv4.BasicCognitoUserPoolsAuthProvider.getLatestAuthToken(BasicCognitoUserPoolsAuthProvider.java:86)
    at com.amazonaws.mobileconnectors.appsync.sigv4.AppSyncSigV4SignerInterceptor.intercept(AppSyncSigV4SignerInterceptor.java:146)
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147) 
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121) 
    at com.amazonaws.mobileconnectors.appsync.retry.RetryInterceptor.intercept(RetryInterceptor.java:40) 
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147) 
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121) 
    at okhttp3.logging.HttpLoggingInterceptor.intercept(HttpLoggingInterceptor.java:221) 
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147) 
    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121) 
    at okhttp3.RealCall.getResponseWithInterceptorChain(RealCall.java:264) 
    at okhttp3.RealCall$AsyncCall.execute(RealCall.java:210) 
    at okhttp3.internal.NamedRunnable.run(NamedRunnable.java:32) 
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636) 
    at java.lang.Thread.run(Thread.java:764)