使用ng-repeat在动态单选按钮上设置值

我在将动态创建的单选按钮组中的值设置为对象时遇到问题。如果ng-model中指定的对象不为null，则不选中单选按钮，单击任何单选按钮都不会触发附加的$ watch。但是，如果加载时ng-model中的object为null，则$ w​​atch似乎可以正常工作。现在，如果我将ng-model的值更改为字符串，则可以正常工作，问题是我需要整个对象。基本上，每个模型都是一个问题，并且在UI中更改问题时，会将整个模型对象发送到Web服务。

数据（已设置值-不起作用）

{
    "__type": "RadioQuestion:#MyProject.Model.Entities",
    "Id": "ff3234ba-40fe-43e3-9457-ea5e3b5ae5a7",
    "Question": "Question goes here",
    "RangeMaxText": "Very likely",
    "RangeMinText": "Not Likely",
    "Title": "Question headline",
    "DefaultValue": {
        "Id": "id-for-no-value",
        "Name": "Nej"
    },
    "PossibleValues": [
        {
            "Id": "id-for-yes-value",
            "Name": "Yes"
        },
        {
            "Id": "id-for-no-value",
            "Name": "No"
        }
    ],
    "Question": "Hows it hanging?",
    "Value": {
        "Id": "id-for-no-value",
        "Name": "Nej"
    }
}

标记

<h4>{{question.Question}}</h4>
<label data-ng-repeat="pValue in question.PossibleValues" for="{{question.Id}}-{{pValue.Id}}">
    <input
        id="{{question.Id}}-{{pValue.Id}}"
        name="radio-for-{{question.Id}}"
        type="radio"
        data-ng-value="pValue"
        data-ng-model="question.Value" />
        {{pValue.Name}}
</label>

数据（值为空-有效）

{
    "__type": "RadioQuestion:#MyProject.Model.Entities",
    "Id": "ff3234ba-40fe-43e3-9457-ea5e3b5ae5a7",
    "Question": "Question goes here",
    "RangeMaxText": "Very likely",
    "RangeMinText": "Not Likely",
    "Title": "Question headline",
    "DefaultValue": {
        "Id": "id-for-no-value",
        "Name": "Nej"
    },
    "PossibleValues": [
        {
            "Id": "id-for-yes-value",
            "Name": "Yes"
        },
        {
            "Id": "id-for-no-value",
            "Name": "No"
        }
    ],
    "Question": "Hows it hanging?",
    "Value": null
}

这是监视功能：

this.$scope.questions.forEach((question) => {
    this.$scope.$watch(
        () => { return question; },
        (newVal, oldVal) => this.updateQuestion(newVal, oldVal),
        true
    );
});