如何在计算中对“desc”中的数组值排序?

我有一个模型值,每次迭代都很好。

<ul>
    <li>See here : </li>
    {{#each selectedCreditCard.balances.tenures as |balance|}}
    <li>Balances is : {{balance}}</li>
    {{/each}}
</ul>

desc 方法所以我用 computed 方法来执行 描述 阵列。

sortTenuresBy:['desc'],
sortedTenures: Ember.computed.sort('selectedCreditCard.balances.tenures', 'sortTenuresBy'),
maxTenure:Ember.computed(function(){
return this.get('sortedTenures').get('firstObject');

Assertion Failed: When using @each to observe the array 3,8,12,24, the array must return an object