微信小程序开发者回答：

页面：

商品

js：
var app = getApp()
Page({
data: {
char_lt: "<",
motto: 'MiHome_Store',
userInfo: {},
indicatorDots: true,
autoplay: true,
interval: 3000,
duration: 100,
show_flag: false,
"banner_list": [
{
"banner": [
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_904608692a4d8415d0de39a0a5897e80.jpeg&w=1080&h=600&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",
},
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_0f5e43035a8b8d27a4b6f315d222fd9b.jpeg&w=1080&h=600&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",
},
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_4ba3d814639ab27570f174467133619f.png&w=1080&h=600&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",
},
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_91f29509f14ea243958285aaf5d5b640.jpeg&w=1080&h=600&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",
},
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_5c752db8097555831469356f5f389078.jpeg&w=1080&h=600&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",
}
]
},
{
"banner": [
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_3237b46c5de819816125d88e9d06b7bf.jpg&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",
},
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_c02bce3048058edb194dc3efb230d06b.jpg&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",
},
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_45b3c9ed56aef44994176b50ae5d8a69.jpg&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",
},
{
"pic_url": "http://static.home.mi.com/app/shop/img?id=shop_95583f54ee857e8fa5f4cf1b9f791a74.jpg&crop=a_0_120_1080_480&t=webp&z=1.15&q=78",


}
]
}
],
},
onPageScroll: function (e) {
var that=this;
if (e.scrollTop >= 485){
that.setData({
show_flag: true
})
}else{
that.setData({
show_flag: false
})
}
},
setGoodsTab:function(){
console.log("aa");
},
onLoad: function () {
}
})