Javascript 为什么我的小提琴演奏不正确？

我希望呈现为树的JSON是

{
    "productOfferings": [
        {
            "text": "Mobile subscription with Internet access 2GB and iPad 32GB",
            "description": "Joors 2GB mobile broadband and iPad 32GB",
            "productOfferings": [
                {
                    "id": 5,
                    "text": "Ipad with 32 GB storage",
                    "description": "A iPad 32 GB Product Offering",
                    "productSpecification": {
                        "id": 5,
                        "text": "IPad",
                        "description": ""
                    }
                },
                {
                    "id": 8,
                    "text": "Mobile subscription with Sim Card and Internet access 2GB",
                    "description": "Mobile subscription with Sim Card and Internet access 2GB",
                    "productSpecification": {
                        "id": 9,
                        "text": "Mobile subscription with sim card and Internet access",
                        "description": "Mobile subscription with sim card and Internet access",
                        "productSpecifications": [
                            {
                                "id": 2,
                                "text": "Mobile subscription with Sim Card",
                                "description": "This is the classic Subscription product of a Mobile Network totally void of Services, so it can only be used for accessing a HPLMN. Simply put a MSISDN + SIM"
                            },
                            {
                                "id": 4,
                                "text": "Mobile Internet access",
                                "description": "This is a GPRS Service for a Mobile Network Access Product for accessing Internet"
                            }
                        ]
                    }
                }
            ]
        }
    ]
}

我想用extJS呈现一棵树，就像在jsonviewer.stack.hu中使用json一样

我试着用小提琴演奏，但没能做到，小提琴有几点很奇怪：

---

当我使根不可见时，它会变成两个根。很奇怪。无法设置displayField，它必须有名称“text”，但我不能因为extJS而更改json。我希望文本字段的名称为“name”。我一直在尝试像jsonviewer.stack那样呈现produtSpecification，但如何实现却令人费解。您能帮助我吗？

作为第一个提示，ID在JSON中必须是唯一的：

作为第一个提示，ID在JSON中必须是唯一的：