Validating user login on application restart

Android
1

Hi. I have problem with user restore on application restart.
Such code:

if(Backendless.UserService.isValidLogin()){
 ...

}

Throw fatal error:
FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{…}: BackendlessException{ code: ‘Internal client exception’, message: ‘null’ }
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
Caused by: BackendlessException{ code: ‘Internal client exception’, message: ‘null’ }
at com.backendless.Invoker$SyncResponder.errorHandler(Invoker.java:127)
But if i use asynchronous version of function all work fine.

Backendless.UserService.isValidLogin(new BackendlessCallback<Boolean>() {
 @Override

 public void handleResponse(Boolean response) {

 ...

 }

});

Any ideas?

2

you should use asynchronous version or isValidLogin in other thread, but better to use