picker 选择器问题

<picker bindchange="bindPayChange" value="{{AccountIndex}}"range-key="{{CarNum}}"  range="{{RemittanceAccount}}">

<view class="picker">

<text class='iconfont icon-xiangxiajiantou'></text>

<text>{{RemittanceAccount[AccountIndex].CarNum}}</text>

</view>

</picker>

谁能告诉我  range-key  range 分别应该怎么 绑定