我想在request之后重置piker和textarea，请问该怎么做？设置什么值？ <view class='view_head'> <view class='view_head_content'> <picker class='pk' bindchange="bindPickerChange" value="{{stockindex}}" range='{{stockNos}}' range-key="{{'value'}}"> <view class="picker">{{stockNos[stockindex].value}}</view> </picker> </view> <view class='view_head_content'> <picker class='pk' mode="date" value="{{date}}" start="{{nowDate}}" end="{{endDate}}" bindchange="bindDateChange"> <view class="picker">{{date}}</view> </picker> </view> <view class='view_head_content'> <textarea class='txtarea' bindinput='remarkInput'></textarea> </view>