微信小程序导航栏滑动定位功能示例(实现CSS3的

<view style="height:100%;position:fixed;width:100%;">
 <scroll-view scroll-y="false" bindscroll="scroll" style="height:100%;">
  <view class="page-bottom-content">
   <text>{{text}}</text>
  </view>
  <view class="page-banner">
   banner
  </view>
  <view class="page-group {{scrollTop > 360 ? 'page-group-position' : ''}}">
   <view class="page-nav-list"><text>首页</text></view>
   <view class="page-nav-list"><text>活动</text></view>
   <view class="page-nav-list"><text>菜单</text></view>
   <view class="page-nav-list"><text>我的</text></view>
  </view>
  <view class="goods-list">
   goods-list
  </view>
 </scroll-view>
</view>

.page-banner{height: 500rpx;background-color: greenyellow;padding: 20rpx;color:#fff;}
.page-group{
 display: table;
 background-color: blueviolet;
 width: 100%;
 table-layout: fixed;
 position: relative;
 : 0;
 left: 0;
}
.page-group-position{
 position: fixed;
}
.page-nav-list{
 padding:30rpx 0 ;
 display: table-cell;
 text-align: center;
 color: #fff;
}
.goods-list{
 height: 2000rpx;
 background-color: green;
 padding: 20rpx;
 color:#fff;
}

Page({
 data: {
  scrollTop: null
 },
 //滚动条监听
 scroll: function (e) {
  this.setData({ scrollTop: e.detail.scrollTop })
 },
})

scrollTop > 360 ? 'page-group-position' : ''

scrollTop > 360 ? 'fixed' : 'relative'