分析
上端导航栏可以放置多个分类，可滑动
点击导航栏最右端按钮可以查看所有分类，同时背景模糊
内容部分右拉跳转到另外的分类
点击分类时导航栏的滑动部分自动滑动到合适的位置
代码展示：
js
/**
* categoryView.js - 分类页面
*/
var fakeData = require('../../common/fakeData.js')
Page(
{
data: {
categories: ['全部'],
currentTab: 0,
scrollLeftValue: 0,
isPickerShow: false,
isBgNeed: false,
commodities: []
},
navbarTap: function (e) {
//将顶部导航栏自动移动到合适的位置
var idx = e.currentTarget.dataset.idx;
this.autoScrollTopNav(idx);
//自动收回
if (this.data.isPickerShow) {
this.navbarBtnClick();
}
this.setData({
currentTab: idx
})
},
/**
* 导航栏右侧箭头按钮点击事件 - 切换模糊背景开闭状态以及展开栏开闭状态
*/
navbarBtnClick: function(e) {
this.data.isBgNeed = !this.data.isPickerShow
this.setData({
isBgNeed: this.data.isBgNeed
})
this.data.isPickerShow = !this.data.isPickerShow
this.setData({
isPickerShow: this.data.isPickerShow,
})
},
/**
* 页面左右滑动事件 - 构造滑动动画，若当前页面无数据，自动加载，需要完善加载函数
*/
swiperChange: function (e) {
var idx = e.detail.current;
this.autoScrollTopNav(idx);
this.setData({
currentTab: e.detail.current,
})
//若无数据，自动加载
if (this.data.commodities[idx].length == 0) {
this.downloadMoreItem();
}
},
/**
* 上拉刷新
*/
updateItem: function(e) {
var idx = this.data.currentTab;
this.data.commodities[idx] = [];
this.downloadMoreItem();
},
/**
* 下载更多数据 - 涉及后台拉取数据，需完善
*/
downloadMoreItem: function(e) {
var idx = this.data.currentTab;
var commodities = this.data.commodities;
//获取更多数据
commodities[idx] = commodities[idx].concat(
fakeData.requestForItemsOfType(commodities[idx].length, 10, this.data.categories[idx])
);
this.setData({
commodities: this.data.commodities
})
console.log(this.data.commodities);
},
/**
* 用于自动调整顶部类别滑动栏滑动距离，使滑动到用户可接受的合适位置，但自适应上还未考虑太周到
* @param {number} idx - The index of currentTap.
*/
autoScrollTopNav: function (idx) {
if (idx <= 2) {
this.data.scrollLeftValue = 0;
} else {
this.data.scrollLeftValue = (idx - 2) * 60;
}
this.setData({
scrollLeftValue: this.data.scrollLeftValue
})
},
/**
* 模糊背景点击事件 - 点击模糊背景取消选择
*/
bgTap: function(e) {
if (this.data.isPickerShow) {
this.navbarBtnClick();
} else {
return;
}
},
/**
* 商品点击事件 - 待完善
*/
itemTap: function(e) {
console.log("you selsct type " + this.data.currentTab + " item " + e.currentTarget.dataset.idx);
},
/**
* 生命周期函数--监听页面加载，在加载的时候抓取数据
*/
onLoad: function (options) {
//首先获取类别项
this.data.categories = fakeData.requestForCategories();
this.setData({
categories: this.data.categories
})
//然后默认请求 全部 分类
for (var i in this.data.categories) {
this.data.commodities.push([]);
}
this.data.commodities[0] = fakeData.requestForItemsOfType(0, 10);
console.log(this.data.commodities);
this.setData({
commodities: this.data.commodities
})
}
})
json
{
"navigationBarTitleText": "商城"
}
wxml
<!--categoryView.wxml-->
<import src="../../common/wxmlTemplate.wxml" />
<!--顶部分类导航条-->
<view class="">
<view class="navbar">
<view class="nav-1">
<scroll-view scroll-x="true" class="nav-1-left" scroll-left="{{scrollLeftValue}}" wx:if="{{!isPickerShow}}">
<view wx:for="{{categories}}" data-idx="{{index}}" class="item {{currentTab==index ? 'active' : ''}}"
wx:key="unique" bindtap="navbarTap">{{item}}</view>
</scroll-view>
<view class="nav-1-left" wx:if="{{isPickerShow}}">
<view class="item left2Font">{{categories[currentTab]}}</view>
</view>
<!-- <view class="blankblock"></view> -->
<button class="navbarBtn" bindtap="navbarBtnClick">
<image src="../../resources/返回.png" class="navbarBtn icon {{isPickerShow ? 'active' : ''}}"></image>
</button>
</view>
<view class="picker" wx:if="{{isPickerShow}}">
<view class="spitLine"></view>
<view class="picker-contain">
<view wx:for="{{categories}}" data-idx="{{index}}" class="item {{currentTab==index ? 'active' : ''}}"
wx:key="unique" bindtap="navbarTap">{{item}}</view>
</view>
</view>
</view>
<swiper class="itemContainer" bindchange="swiperChange" current="{{currentTab}}">
<block wx:for="{{categories}}" wx:for-item="cItem" wx:key="unique">
<swiper-item>
<scroll-view scroll-y="true" bindscrolltolower="downloadMoreItem" bindscrolltoupper="updateItem">
<view class="child" bindtap="itemTap" wx:for="{{commodities[currentTab]}}"
data-idx="{{index}}" wx:key="unique" wx:if="{{item.category == cItem || cItem == '全部'}}">
<template is="itemInfoTemplate" data="{{item}}"/>
</view>
</scroll-view>
</swiper-item>
</block>
</swiper>
<!-- 透明遮盖层 -->
<view class="picker-contain-bg {{isPickerShow? 'show' : ''}}" wx:if="{{isBgNeed}}" bindtap="bgTap"></view>
</view>
wxss
@import "../../common/flexGridStyle.wxss";
@import "../../common/itemShowStyle.wxss";
page {
display: flex;
flex-direction: column;
height: 100%;
}
.navbar {
position: fixed;
z-index: 2;
background-color: RGB(247, 247, 247);
width: 100%
}
.nav-1{
flex: none;
display: flex;
background: #fff;
background-color: RGB(247, 247, 247);
height: 80rpx;
}
.nav-1 .wrapBar {
display: flex;
}
.nav-1 .item{
position: relative;
text-align: center;
font-size: 30rpx;
line-height: 80rpx;
color: gray;
display: inline-block;
padding-left: 20rpx;
padding-right: 20rpx;
}
.nav-1 .item.active{
color: black;
}
.nav-1 .item.active:after{
content: "";
display: block;
position: absolute;
bottom: 0;
left: 0;
right: 0;
height: 4rpx;
background: black;
}
button {
background: transparent;
}
button::after {
border: 0;
}
.navbarBtn {
flex: 0 0 15%;
}
.navbarBtn.icon {
transform: rotate(90deg);
width: 20rpx;
height: 40rpx;
}
.navbarBtn.icon.active{
transform: rotate(-90deg);
}
.blankblock {
flex: 0 0 10%;
}
.nav-1-left {
white-space: nowrap;
overflow: hidden;
flex: 0 0 85%;
}
.picker {
}
.item.left2Font {
color: black;
}
.spitLine {
margin: 0;
height: 2rpx;
background-color: gray;
}
.picker-contain {
display: flex;
flex-wrap: wrap;
justify-content: center;
}
.picker-contain-bg {
position: fixed;
background-color: black;
transition: all 1s;
width: 100%;
height: 100%;
z-index: 1;
top: 0;
opacity: 0
}
.picker-contain-bg.show {
opacity: 0.5;
}
.picker-contain .item {
background-color: RGB(215, 215, 215);
border-radius:20px;
margin: 20rpx;
padding: 50rpx;
padding-top: 10rpx;
padding-bottom: 10rpx;
font-size: 30rpx;
color: RGB(161, 161, 161);
}
.picker-contain .item.active{
color: black;
background-color: RGB(153, 153, 153);
}
swiper-item scroll-view {
display: inline;
}
swiper.itemContainer{
margin-top: 80rpx;
height: 1136rpx;
}
