数组上的orderByChild（）

Question

我使用Firebase for Android，发现orderByChild("key")方法似乎不适用于数组;我尝试检索按award_year值排序的所有year条目。

这就是我提出的：

mDatabase.child("awards").orderByChild("createdAt").addValueEventListener(new ValueEventListener() {
      @Override
      public void onDataChange(DataSnapshot dataSnapshot) {
         final AwardType awardType = new AwardType();
         final ArrayList<Award> awards = dataSnapshot.getValue(awardType);
      }
});

非常感谢您的帮助。

我已添加规则：

我的结构如下：

{ "awards": [
    {
        "award_body": "2009 QR Master Design Awards",
        "award_received": "Finalist for Bathrooms $30,000, Qualified Remodeler Magazine",
        "createdAt": "2015-11-20T03:43:58.009Z",
        "logo": {
            "__type": "File",
            "name": "tfss-b2a0130d-d9ac-46e6-a29f-c9d9db666909-qualirem1.png",
            "url": "awards/thumbnails/tfss-b2a0130d-d9ac-46e6-a29f-c9d9db666909-qualirem1.png"
        },
        "objectId": "0cE0zA7ciS",
        "updatedAt": "2015-11-20T03:46:57.472Z",
        "year": {
            "__type": "Pointer",
            "className": "award_years",
            "objectId": "Zp3oDtzpTY"
        }
    },
    {
        "award_body": "2014 NAHB",
        "award_received": "Best of American Living Awards (BALA) Platinum Award Winner, Kitchen Remodel $100,001 \u0026 over",
        "createdAt": "2015-11-20T05:36:55.359Z",
        "logo": {
            "__type": "File",
            "name": "tfss-3cce2507-18fe-4aac-b039-54c343f27473-nahb.png",
            "url": "awards/thumbnails/tfss-3cce2507-18fe-4aac-b039-54c343f27473-nahb.png"
        },
        "objectId": "1ckh7kjxfN",
        "updatedAt": "2015-11-20T05:45:02.307Z",
        "year": {
            "__type": "Pointer",
            "className": "award_years",
            "objectId": "aL7crUC7Qc"
        }
    }]
}