Angular中的KendoUI Grid聚合

Question

我正在使用KendoUI网格并尝试依靠字段。我在另一个领域获得总和，这不会引起任何错误。令人惊讶的是，count也会返回值，但在控制台中会出现一堆错误 - TypeError：无法读取属性＆＃39; count＆＃39;未定义。这是我的HTML，请指教：

    <kendo-grid [data]="gridData"
            [pageSize]="state.take"
            [skip]="state.skip"
            [sort]="state.sort"
            [sortable]="true"
            [pageable]="true"
            [scrollable]="'scrollable'"
            [groupable]="true"
            [group]="state.group"
            [filterable]="true"
            [filter]="state.filter"
            (dataStateChange)="dataStateChange($event)"
            [height]="500">
    <kendo-grid-column field="EmployeeID" title="Employee ID" width="150" filter="numeric">
        <ng-template kendoGridFooterTemplate
                     let-column="column">Tot Reps:{{aggregates["EmployeeID"].count}}</ng-template>
    </kendo-grid-column>
    <kendo-grid-column field="TotalHours" title="Total Hours" width="150" filter="numeric">
        <ng-template kendoGridGroupFooterTemplate
                     let-group="group"
                     let-aggregates>Sum:{{aggregates["TotalHours"].sum}}</ng-template>
        <ng-template kendoGridFooterTemplate
                     let-column="column">Tot Hours:{{total["TotalHours"]?.sum}}</ng-template>
    </kendo-grid-column>

</kendo-grid>