我正在使用laravel 5.5 API资源集合来显示产品列表。我正在使用数组而不是模态对象。我得到了项目列表，但我不确定如何在响应中显示项目变量数组。传递到API资源的实际响应数组为：

{
"ID": 3160,
"UserID": 3302,
"ItemName": "2",
"Description": "2",
"Price": 2,
"StockLimited": true,
"StockQuantity": 19,
"CurrencyCode": "USD",
"ImageUrl": "/images/items/Item3302-636434761494584365-qq5HFm.png",
"VariantItems": [
  {
    "ID": 3181,
    "ItemName": "2",
    "Price": 0,
    "StockLimited": false,
    "StockQuantity": 0,
    "CurrencyCode": "USD",
    "Variants": [
      {
        "Id": 1099,
        "Name": "Red",
        "VariantGroupId": 1027,
        "VariantGroupName": "Colour"
      },
      {
        "Id": 1111,
        "Name": "S",
        "VariantGroupId": 1028,
        "VariantGroupName": "Size"
      }
    ]
  },
  {
    "ID": 3182,
    "ItemName": "2",
    "Price": 0,
    "StockLimited": false,
    "StockQuantity": 0,
    "CurrencyCode": "USD",
    "Variants": [
      {
        "Id": 1099,
        "Name": "Red",
        "VariantGroupId": 1027,
        "VariantGroupName": "Colour"
      },
      {
        "Id": 1112,
        "Name": "M",
        "VariantGroupId": 1028,
        "VariantGroupName": "Size"
      }
    ]
  }

],
"MerchantName": "seller",
"VariantGroupLists": [
  {
    "VariantGroupName": "Colour",
    "Names": [
      "Red",
      "Grey",
      "Navy"
    ]
  },
  {
    "VariantGroupName": "Size",
    "Names": [
      "S",
      "M",
      "L",
      "XL"
    ]
  }
]  
}

我的项目资源集合

public function toArray($request)
{

    return [
        'data' => $this->collection->map(function ($item) use ($request) {
            return (new ItemResource($item))->toArray($request);
        })
    ];
}

我的项目资源

public function toArray($request)
{

    return [
        "item_id" => $this->resource->ID,
        "item_name" => $this->resource->ItemName,
        "description" =>$this->resource->Description,
        "item_price"=>$this->resource->Price,
        "stock_qty"=>$this->resource->StockQuantity,
        "currency_code"=>$this->resource->CurrencyCode,
        "item_image_url"=>$this->resource->ImageUrl,

    ];

}

public function with($request)
{

    return ['item_varients' => [new ItemResource($this->resource->VariantItems)]]; 
}

我试图达到的是这样的结果：

[

{
    "item_id": 3160,
    "item_name": "BLACK COWL NECK DRESS WITH DIAMANTE DETAIL",
    "description": "Test test",
    "item_price": 16.99,
    "stock_qty": 20,
    "currency_code": "SGD",
    "item_image_url": "/images/items/Item18-636231488325192562-GoiIBl.png",
    "item_varients": [
      {
        "id": 29,
        "name": "Red",
        "varientgroupId": 11,
        "varientgroupname": "Color"
      }
    ]
  }
]

ItemResource中的with()方法不起作用。如何在资源响应中添加"item_varients"数组？