Flutter / OneSignal：我在使用 postNotificationWithJson 时遇到问题

Question

作为新手开发人员，我正在为我制作一个应用程序，我希望用户使用我的应用程序中的 onesignal postNotificationWithJson（和过滤器）功能按设备上的位置发送通知，但我收到一个错误，我一直在处理这个问题错误 2 天，但我还没有找到解决方案。

错误：

OneSignalRestClient: POST RECEIVED JSON: {"errors":["Please include a case-sensitive header of Authorization: Basic \u003cYOUR-REST-API-KEY-HERE\u003e with a valid REST API key."],"reference":["https://documentation.onesignal.com/docs/accounts-and-keys#section-keys-ids"]}
W/OneSignal( 7314): HTTP code: 400 create notification failed
E/flutter ( 7314): [ERROR:flutter/lib/ui/ui_dart_state.cc(184)] Unhandled Exception: PlatformException(OneSignal, Encountered an error attempting to post notification: {"errors":["Please include a case-sensitive header of Authorization: Basic <YOUR-REST-API-KEY-HERE> with a valid REST API key."],"reference":["https:\/\/documentation.onesignal.com\/docs\/accounts-and-keys#section-keys-ids"]}, {reference: [https://documentation.onesignal.com/docs/accounts-and-keys#section-keys-ids], errors: [Please include a case-sensitive header of Authorization: Basic <YOUR-REST-API-KEY-HERE> with a valid REST API key.]}, null)

代码（删除过滤器行时错误消失。）：

    var response = await OneSignal.shared.postNotificationWithJson({
  "Authorization":
      "Basic xxxxx",
  "filters": [
    {
      "field": "location",
      "lat": "36.1185207",
      "long": "36.2526271",
      "radius": "800",
    }
  ],

  "headings": {"en": "APP NAME"},
  "contents": {"en": "Click for more information."},
  "data1": {"name": "Markos", "LastName": "Baslik"},
  "data2": {"idName": "KNARNYR"},
});