获取别名，程序崩溃

[liuweichn]

/// 获取别名
FlutterJPush.getAlias().then((JPushResult result) {
if (result.isOk) {
print('alias: ${result.result}');
}
});

报错：E/AndroidRuntime: FATAL EXCEPTION: MessageReceiver
Process: com.gxanxun.smart_maintenance, PID: 21978
java.lang.RuntimeException: Methods marked with @UiThread must be executed on the main thread. Current thread: MessageReceiver
at io.flutter.embedding.engine.FlutterJNI.ensureRunningOnMainThread(FlutterJNI.java:807)
at io.flutter.embedding.engine.FlutterJNI.invokePlatformMessageResponseCallback(FlutterJNI.java:740)
at io.flutter.embedding.engine.dart.DartMessenger$Reply.reply(DartMessenger.java:156)
at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler$1.success(MethodChannel.java:225)
at com.jzoom.flutterjpush.FlutterJPushPlugin$MyJPushMessageReceiver.onAliasOperatorResult(FlutterJPushPlugin.java:766)
at cn.jpush.android.a.b.run(Unknown Source)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.os.HandlerThread.run(HandlerThread.java:61)