?? ?????? ??? ???? ????? ??? ??? ?? ? ???? ?? ????? ??? ???? ???? ? ?? WeChat ???? ???? ??? ???????. ??? ??? ????.

1. ??

?? ???? ?? ????? ??? ???, ??? ???? ????? ??? ??? ?? ???? ??????. ? ?? ???? ?? ???? ?????.

??? ?? ??????.

??? ?? ??? ??? ?? ????? ????. ?? ?? ?? ??? ??? ??? ????.

2. ??

2.1 ?? ??

? ?? ??? ?? WeChat ???? ?? scroll-view ?? ??? ?????.

scroll-into-view ??? ???? ??? ? ???? ???? ??? ?? ??? ???? ???? ? ????.

binscroll ???? ???? ?? ???? ??? ??? ???? ?? ???? ?? ????. ??? ??

2.1 ??? ???? ??

?? ?????? ?? ????? ?? ???? ?????. ?????? ?? ?? ?? ?? + ??? ?? ?? ??? ? ???? ????.

??? ??? ?? ??? ?? ???? ?? ???? ???? ? ??? ????? ???.

?? ??:

<!--index.wxml-->
<view class="list">

<!--頂部固定區(qū)域-->
<view style="height: 88rpx;width: 100%;background-color: burlywood;text-align: center;">頭部區(qū)域</view>

<!--可滾動區(qū)域-->
<scroll-view scroll-y="true" style="width: 100%; height: {{scrollAreaHeight}}px;" bindscroll="scroll" scroll-into-view="{{scrollToItem}}" scroll-with-animation="true"  scroll-top="{{scrollTop}}">

   <!--水平滾動的tab欄-->
  <scroll-view scroll-x="true" style="height: 88rpx;width: 100%;">
  <view class="head-area {{float ? &#39;head-float&#39; : &#39;&#39;}}" >
    <view class="head-area-item {{curSelectTab === index ? &#39;head-area-item-select&#39; : &#39;&#39;}}" wx:for="{{appGroupList}}" bindtap="tabClick" data-index="{{index}}">
    {{item.name}}
  </view>
  </view>

  </scroll-view>

<!--數(shù)據(jù)列表-->
<view class="list-group" style="height: {{listGroupHeight}}px;">
  <view class="list-group-item" id="v_{{index}}" wx:for="{{appGroupList}}" data-index="{{index}}">
    <view class="group-name">
      {{item.name}}
    </view>
    <view class="group-children" >
      <view wx:for="{{item.children}}" class="group-children-item" style="width: {{itemWidth}}px;">
      <image src="{{item.url}}"></image>
      <view>{{item.name}}</view>
    </view>
    </view>

  </view>
</view> 
</scroll-view>

</view>

???? ???? ???? ? ? ?? ??? ????.

1. ??? ??? scrollAreaHeight ?? ??. --- ?? ??? ? ???? ?? ?? ??? ??? ? ?? ????

2. ?? ??? ??? ??? ??. --- ???? ??? ??? ???? ??? ??? ?? ??? ???? ??? ?? ?? ???? ?????.

3. {index}}" ??? ??? ID? ??? ? ??? ???? ??? ??? ???? ? ID? ???? ?????.

2.2 ??? ??

/**index.wxss**/
.list{
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
}

.head-area{
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  height: 88rpx;
  width: 100%;
  padding: 0 10;
}

.head-area-item{
  display: flex;
  height: 88rpx;
  text-align: center;
  width: 150rpx;
  align-items: center;
  justify-content: center;
}

.head-area-item-select{
  color: #09bb07;
}

image{
  width: 88rpx;
  height: 88rpx;
}

.list-group{
  display: flex;
  width: 100%;
  height: 1000%;
  flex-direction: column;
}

.list-group-item{
  display: flex;
  width: 100%;
  background-color: #aaa;
  flex-direction: column;
}

.group-name{
  height: 88rpx;
  display: flex;
  text-align: center;
  align-items: center;
  margin-left: 20rpx;
}

.group-children{
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  width: 100%;
}

.group-children-item{
  height: 160rpx;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.head-float{
  position: fixed;
  top: 88rpx;
  background-color: #ffffff;
}

2.3 ?? ??

// index.js
Page({
  heightArr: [],
  //記錄scroll-view滾動過程中距離頂部的高度
  distance: 0,
  data: {
    appGroupList:[
      {name:"分組01",children:[{"name":"測試0","url":"/images/bluetooth.png"},
      {"name":"測試1","url":"/images/bluetooth.png"},
      {"name":"測試2","url":"/images/bluetooth.png"},
      {"name":"測試3","url":"/images/bluetooth.png"},
      {"name":"測試4","url":"/images/bluetooth.png"},
      {"name":"測試5","url":"/images/bluetooth.png"},
      {"name":"測試6","url":"/images/bluetooth.png"},
      {"name":"測試7","url":"/images/bluetooth.png"}]},
      {name:"分組02",children:[{"name":"測試0","url":"/images/bluetooth.png"},
      {"name":"測試1","url":"/images/bluetooth.png"},
      {"name":"測試2","url":"/images/bluetooth.png"},
      {"name":"測試3","url":"/images/bluetooth.png"},
      {"name":"測試4","url":"/images/bluetooth.png"},
      {"name":"測試5","url":"/images/bluetooth.png"},
      {"name":"測試6","url":"/images/bluetooth.png"},
      {"name":"測試7","url":"/images/bluetooth.png"}]},
      {name:"分組03",children:[{"name":"測試0","url":"/images/bluetooth.png"},
      {"name":"測試1","url":"/images/bluetooth.png"},
      {"name":"測試2","url":"/images/bluetooth.png"},
      {"name":"測試3","url":"/images/bluetooth.png"},
      {"name":"測試4","url":"/images/bluetooth.png"},
      {"name":"測試5","url":"/images/bluetooth.png"},
      {"name":"測試6","url":"/images/bluetooth.png"},
      {"name":"測試7","url":"/images/bluetooth.png"}]},
      {name:"分組04",children:[{"name":"測試0","url":"/images/bluetooth.png"},
      {"name":"測試1","url":"/images/bluetooth.png"},
      {"name":"測試2","url":"/images/bluetooth.png"},
      {"name":"測試3","url":"/images/bluetooth.png"},
      {"name":"測試4","url":"/images/bluetooth.png"},
      {"name":"測試5","url":"/images/bluetooth.png"},
      {"name":"測試6","url":"/images/bluetooth.png"},
      {"name":"測試7","url":"/images/bluetooth.png"}]},
      {name:"分組05",children:[{"name":"測試0","url":"/images/bluetooth.png"},
      {"name":"測試1","url":"/images/bluetooth.png"},
      {"name":"測試2","url":"/images/bluetooth.png"},
      {"name":"測試3","url":"/images/bluetooth.png"},
      {"name":"測試4","url":"/images/bluetooth.png"},
      {"name":"測試5","url":"/images/bluetooth.png"},
      {"name":"測試6","url":"/images/bluetooth.png"},
      {"name":"測試7","url":"/images/bluetooth.png"}]},
    ],
    itemWidth: wx.getSystemInfoSync().windowWidth / 4,
    scrollAreaHeight:wx.getSystemInfoSync().windowHeight - 44,
    float:false,
    curSelectTab:0,
    scrollToItem:null,
    scrollTop: 0, //到頂部的距離
    listGroupHeight:0,
  },

  onReady: function () {
    this.cacluItemHeight();
  },

  scroll:function(e){
    console.log("scroll:",e);
    if(e.detail.scrollTop>=44){
      this.setData({
        float : true
      })
    } else if(e.detail.scrollTop<44) {
      this.setData({
        float : false
      })
    }
    let scrollTop = e.detail.scrollTop;
    let current = this.data.curSelectTab;
    if (scrollTop >= this.distance) {
      //頁面向上滑動
      //列表當(dāng)前可視區(qū)域最底部到頂部的距離 超過 當(dāng)前列表選中項距頂部的高度（且沒有下標(biāo)越界），則更新tab欄
      if (current + 1 < this.heightArr.length && scrollTop >= this.heightArr[current]) {
        this.setData({
          curSelectTab: current + 1
        })
      }
    } else { 
      //頁面向下滑動
      //如果列表當(dāng)前可視區(qū)域最頂部到頂部的距離 小于 當(dāng)前列表選中的項距頂部的高度，則切換tab欄的選中項
      if (current - 1 >= 0 && scrollTop < this.heightArr[current - 1]) {
        this.setData({
          curSelectTab: current - 1
        })
      }
    }
    //更新到頂部的距離
    this.distance = scrollTop;
  },

  tabClick(e){
    this.setData({
      curSelectTab: e.currentTarget.dataset.index,
      scrollToItem: "v_"+e.currentTarget.dataset.index
    })
  },

  //計算每一個item高度
  cacluItemHeight() {
    let that = this;
    this.heightArr = [];
    let h = 0;
    const query = wx.createSelectorQuery();
    query.selectAll(&#39;.list-group-item&#39;).boundingClientRect()
    query.exec(function(res) {
      res[0].forEach((item) => {
        h += item.height;
        that.heightArr.push(h);
      })
      console.log(that.heightArr);
      that.setData({
        listGroupHeight: that.heightArr[that.heightArr.length - 1 ]
      })
    })
  },
})

?? ???? ? ?? ?? ??? ????.

1 cacluItemHeight? ??? ?? ??? ?? ??? ???? ?? ?? ??? heightArr ??? ?????.

heightArr ??? ? ?? ?? ?? ??? ???? ?????.

2. ????? ?? ??? ??? ????, ???? ???? ?? ??? ??? ??, ??? ??? ???? ?? ??? ?? ?????.

?????. ? ??? ???? ????? ??? ??? ?? ? ? ?? ??? ?? ? ????.

【?? ?? ??: ?? ???? ?? ????】

? ??? ?? ?????? ?? ???? ?? ?? ??? ???? ??? ?? ??? ??? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!