html:
<view class="content">内容</view>
<view class="backTop" bindtap='backTop' wx:if="{{backTopValue ==true}}">totop</view>
css:
/*浮窗返回顶部*/
.content {
width: 300rpx;
height: 5000rpx;
border: 1px solid red;
}
.backTop {
position: fixed;
right: 20rpx;
bottom: 130rpx;
}
js:
data: {
// top标签显示(默认不显示)
backTopValue: false
},
// 监听滚动条坐标
onPageScroll: function(e) {
//console.log(e)
var that = this
var scrollTop = e.scrollTop
var backTopValue = scrollTop > 500 ? true : false
that.setData({
backTopValue: backTopValue
})
},
// 滚动到顶部
backTop: function() {
// 控制滚动
wx.pageScrollTo({
scrollTop: 0
})
},