Google SignIn not working

问题

I have an Android app for a customer, who wishes the users be able to log in via Google. So far, I have implemented the Google SignInButton, the GoogleSignInOptions, and the GoogleApiClient.

However, when I try to log in with:

googleApiClient.connect(GoogleApiClient.SIGN_IN_MODE_REQUIRED);

the application force quits as soon as it is opened with following exception:

E/AndroidRuntime: FATAL EXCEPTION: main
                                                                 Process: de.nwt.slottynative, PID: 24509
                                                                 java.lang.RuntimeException: Unable to start activity ComponentInfo{de.nwt.slottynative/de.nwt.slottynative.FullscreenActivity}: java.lang.IllegalStateException: Cannot use sign-in mode: SIGN_IN_MODE_REQUIRED. Mode was already set to SIGN_IN_MODE_NONE
                                                                     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2739)
                                                                     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2804)
                                                                     at android.app.ActivityThread.access$900(ActivityThread.java:181)
                                                                     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1473)
                                                                     at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                     at android.os.Looper.loop(Looper.java:145)
                                                                     at android.app.ActivityThread.main(ActivityThread.java:6066)
                                                                     at java.lang.reflect.Method.invoke(Native Method)
                                                                     at java.lang.reflect.Method.invoke(Method.java:372)
                                                                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
                                                                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
                                                                  Caused by: java.lang.IllegalStateException: Cannot use sign-in mode: SIGN_IN_MODE_REQUIRED. Mode was already set to SIGN_IN_MODE_NONE
                                                                     at com.google.android.gms.internal.zzmg.zzbC(Unknown Source)
                                                                     at com.google.android.gms.internal.zzmg.connect(Unknown Source)
                                                                     at de.nwt.slottynative.FullscreenActivity.onCreate(FullscreenActivity.java:239)
                                                                     at android.app.Activity.performCreate(Activity.java:6368)
                                                                     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
                                                                     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2692)
                                                                     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2804) 
                                                                     at android.app.ActivityThread.access$900(ActivityThread.java:181) 
                                                                     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1473) 
                                                                     at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                                     at android.os.Looper.loop(Looper.java:145) 
                                                                     at android.app.ActivityThread.main(ActivityThread.java:6066) 
                                                                     at java.lang.reflect.Method.invoke(Native Method) 
                                                                     at java.lang.reflect.Method.invoke(Method.java:372) 
                                                                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399) 
                                                                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194) 

If I try to log in with:

googleApiClient.connect();

I am redirected to the account selection fragment, however, the login fails:

03-17 15:30:53.005 27135-27135/de.nwt.slottynative D/handleSignInResult: handleSignInResult: false
03-17 15:30:53.015 27135-27135/de.nwt.slottynative D/handleSignInResult: status: Status{statusCode=unknown status code: 12501, resolution=null}

Here is the code which initializes the API:

//<editor-fold desc="Google SDK Init" >
    googleSignInOps = new GoogleSignInOptions.Builder().requestEmail().requestId().requestProfile()
            .requestIdToken("1042722069660-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.apps.googleusercontent.com").build();
    googleApiClient = new GoogleApiClient.Builder(this).enableAutoManage(this, new GoogleApiClient.OnConnectionFailedListener() {
        @Override
        public void onConnectionFailed(ConnectionResult connectionResult) {
            onGoogleConnectionFailed(connectionResult);
        }
    }).addApi(Auth.GOOGLE_SIGN_IN_API, googleSignInOps).build();
    googleApiClient.connect();
    googleLoginButton = (SignInButton)findViewById(R.id.googleLogin);
    googleLoginButton.setSize(SignInButton.SIZE_WIDE);

    googleLoginButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if (v.getId() == googleLoginButton.getId())
                signIn();
        }
    });
    //</editor-fold>

Thanks in advance for your help!

回答1:

If you're using the SignIn API you should connect with the mode - GoogleApiClient.SIGN_IN_MODE_OPTIONAL:

googleApiClient.connect(GoogleApiClient.SIGN_IN_MODE_OPTIONAL)

Note that if permissions and scopes you have requested through the SignInOptions are not granted by the user the client will still connect successfuly.

来源：https://stackoverflow.com/questions/36063607/google-signin-not-working