picker-view设置了value，实际不生效。。。请问如何处理？ [图片] JS     //生成年月日时分秒     let date = new Date()     let years = []     let months = []     let days = []     let hours = []     let minutes = []     let seconds = []     for (let i = 1990; i <= date.getFullYear(); i++) {       years.push(i)     }     for (let i = 1; i <= 12; i++) {       months.push(i)     }     for (let i = 1; i <= 31; i++) {       days.push(i)     }     for (let i = 0; i <= 23; i++) {       hours.push(i)     }     for (let i = 0; i <= 59; i++) {       minutes.push(i)       seconds.push(i)     }     _this.setData({       years: years,       months: months,       days: days,       hours: hours,       minutes: minutes,       seconds: seconds,       followupdatetimeValue: [9999, 9, 2, 1, 21, 11],     }) WXML     <picker-view indicator-style="height: 50px;" style="width: 100%; height: 50vh;" value="{{followupdatetimeValue}}"       bindchange="followupdatetimeChange">       <picker-view-column>         <view wx:for="{{years}}" wx:for-item="item" style="line-height: 50px; text-align: center;">{{item}}年         </view>       </picker-view-column>       <picker-view-column>         <view wx:for="{{months}}" wx:for-item="item" wx:for-index="idx" style="line-height: 50px; text-align: center;">{{item}}月         </view>       </picker-view-column>       <picker-view-column>         <view wx:for="{{days}}" wx:for-item="item"  style="line-height: 50px; text-align: center;">{{item}}日</view>       </picker-view-column>       <picker-view-column>         <view wx:for="{{hours}}" wx:for-item="item"  style="line-height: 50px; text-align: center;">{{item}}时         </view>       </picker-view-column>       <picker-view-column>         <view wx:for="{{minutes}}" wx:for-item="item"  style="line-height: 50px; text-align: center;">{{item}}分         </view>       </picker-view-column>       <picker-view-column>         <view wx:for="{{seconds}}" wx:for-item="item"  style="line-height: 50px; text-align: center;">{{item}}秒         </view>       </picker-view-column>     </picker-view>