1500字范文 > 微信小程序实现音乐播放器（4）（使用pubsubjs实现页面间通信）

微信小程序实现音乐播放器（4）（使用pubsubjs实现页面间通信）

时间：2018-11-15 17:14:45

文章目录

前情提要消息订阅与发布的基本使用小程序项目app.jsonapp.wxssapp.jspages/index/index.jsonpages/index/index.wxmlpages/index/index.wxsspages/index/index.jspages/music/music.jsonpages/music/music.wxmlpages/music/music.wxsspages/music/music.js相关链接

前情提要

消息订阅与发布的基本使用

npm install --save pubsub-js，安装第三方库pubsub-js。import PubSub from "pubsub-js"，引入第三方库pubsub。订阅消息：id = PubSub.subscribe(消息名,callback)，且callback的第一个形参默认是消息名，后面则是开发者自己传入的参数。发布消息：PubSub.publish(消息名,开发者的参数)。取消订阅：PubSub.unsubscribe(id)。

小程序项目

初始化项目。小程序根目录下执行npm init -y，自动生成package.json。下载安装依赖。npm install --save pubsub-js。页面pages/music/music.js中引入依赖。import PusSub from "pubsub-js"。

遇到如下报错：页面【pages/music/music]错误:

Error: module ‘pages/music/pubsub-js.js’ is not defined, require args is ‘pubsub-js’。微信开发者工具中，工具>构建npm，会自动把node_modules中的第三方依赖转换成小程序可以使用的包，并保存在同级文件夹miniprogram_npm中。

消息订阅：消息ID=PubSub.subscribe(消息名,(msgName,接收的数据) => {})

取消订阅：PubSub.unsubscribe(消息ID)

消息发布：PubSub.publish(消息名,发送的数据)

小程序代码涉及的主要文件有：

app.jsonapp.wxssapp.jspages/index/index.jsonpages/index/index.wxmlpages/index/index.wxsspages/index/index.jspages/music/music.jsonpages/music/music.wxmlpages/music/music.wxsspages/music/music.js

app.json

{"pages": ["pages/index/index","pages/music/music"],"window": {"navigationBarBackgroundColor": "#624d2e","navigationBarTitleText": "首页","navigationBarTextStyle": "white"},"requiredBackgroundModes": ["audio"],"style": "v2","sitemapLocation": "sitemap.json"}

app.wxss

page{height: 100%;}

app.js

App({globalData:{isPlayGlobal:false, //当前是否有歌曲在播放musicIdGlobal:''//当前正在播放的歌曲是哪首}})

pages/index/index.json

{"usingComponents": {},"navigationBarTitleText": "播放列表"}

pages/index/index.wxml

<view class="index-container"><view class="header"><image src="/static/images/icon-play-square.png"></image><text>播放全部</text><text>{{musicList.length}}</text></view><scroll-view class="music-list" enable-flex scroll-y ><view class="music-item" wx:for="{{musicList}}" wx:key="id" bindtap="handleTap" data-musicindex="{{index}}" data-musicitem="{{item}}"><view class="music-index">{{index+1}}</view><image class="music-image" src="{{item.picUrl}}"></image><view class="music-info"><view class="musci-name">{{item.name}}</view><view class="music-author">{{item.author}}</view></view><image class="btn-more" src="/static/images/icon-more.png"></image></view></scroll-view></view>

pages/index/index.wxss

.index-container{padding: 20rpx;background:#624d2e}.header{display: flex;align-items: center;}.header image{width: 28rpx;height: 28rpx;margin-right: 20rpx;}.header text{color: #fff;height: 28rpx;line-height: 28rpx;margin-right: 20rpx;font-size: 28rpx;}.music-list{margin-top: 20rpx;color: #fff;height: calc(100vh - 88rpx);}.music-item{display: flex;align-items: center;height: 100rpx;margin: 20rpx 0;position: relative;}.music-item .music-index{width: 50rpx;font-size: 28rpx;color: #aaa;}.music-item .music-image{width: 80rpx;height: 80rpx;border-radius: 6rpx;margin-right: 20rpx;}.music-item .music-info{display: flex;flex-direction: column;}.music-item .music-info .music-author{font-size: 24rpx;color: #aaa;margin-top: 10rpx;}.music-item .btn-more{width: 36rpx;height: 36rpx;position: absolute;right: 0;}

pages/index/index.js

import PubSub from "pubsub-js";const host = "http://localhost:3000";Page({data:{musicList:[], //歌曲列表musicindex:0 //进入某首歌曲后，记录该歌曲在列表中的索引},onLoad(){this.getDataFromServer();//接收消息，接收来自页面pages/music/music的消息，根据“上一首”or“下一首”，确定当前应该显示哪首歌曲PubSub.subscribe("switchsong",(msgName,type) => {// console.log(msgName,type);let {musicindex,musicList} = this.data;if(type === "prev"){if(musicindex===0) {musicindex = musicList.length-1;}else{musicindex--;}}else if(type === "next"){if(musicindex === musicList.length-1){musicindex = 0;}else{musicindex++;}}this.setData({musicindex});const music = musicList[musicindex];//发送消息，告诉页面pages/music/music，告诉它切换完成后的歌曲的详细消息。PubSub.publish("refreshmusic",music);})},getDataFromServer(){const result = [{id:"001",name:"滂沱大雨里","author":"李若溪","picUrl":host+"/images/滂沱大雨里.jpg","url":host+"/audios/滂沱大雨里.mp3",duration:161000},{id:"002",name:"Last Dance","author":"伍佰","picUrl":host+"/images/Last Dance.jpg","url":host+"/audios/Last Dance.mp3",duration:271000},{id:"003",name:"国王与乞丐","author":"华晨宇","picUrl":host+"/images/国王与乞丐.jpg","url":host+"/audios/国王与乞丐.mp3",duration:178000},{id:"004",name:"奇洛李维斯回信","author":"薛凯琪","picUrl":host+"/images/奇洛李维斯回信.jpg","url":host+"/audios/奇洛李维斯回信.mp3",duration:243000},{id:"005",name:"红日","author":"李克勤","picUrl":host+"/images/红日.jpg","url":host+"/audios/红日.mp3",duration:291000},{id:"006",name:"快乐崇拜","author":"潘玮柏张韶涵","picUrl":host+"/images/快乐崇拜.jpg","url":host+"/audios/快乐崇拜.mp3",duration:329000},{id:"007",name:"门没锁","author":"黄品冠","picUrl":host+"/images/门没锁.jpg","url":host+"/audios/门没锁.mp3",duration:233000},{id:"008",name:"就是爱你","author":"陶喆","picUrl":host+"/images/就是爱你.jpg","url":host+"/audios/就是爱你.mp3",duration:340000},{id:"009",name:"快乐的小青蛙","author":"刘士鸣","picUrl":host+"/images/快乐的小青蛙.jpg","url":host+"/audios/快乐的小青蛙.mp3",duration:130000},{id:"0010",name:"友情岁月","author":"陈小春郑伊健谢天华林晓峰钱嘉乐","picUrl":host+"/images/友情岁月.jpg","url":host+"/audios/友情岁月.mp3",duration:209000},{id:"0011",name:"温柔","author":"五月天","picUrl":host+"/images/温柔.jpg","url":host+"/audios/温柔.mp3",duration:269000}];this.setData({musicList:result});},handleTap(event){const {musicitem,musicindex} = event.currentTarget.dataset;this.setData({musicindex})wx.navigateTo({url: '/pages/music/music?musicitem='+JSON.stringify(musicitem),})}})

pages/music/music.json

{"usingComponents": {},"navigationBarBackgroundColor": "#2f434e","navigationBarTitleText": "音乐详情"}

pages/music/music.wxml

<view class="music-container"><view class="music-name">{{music.name}}</view><view class="music-author">{{music.author}}</view><image class="arm {{isPlay&&'arm-reset'}}" src="/static/images/arm.png"></image><view class="disc-container {{isPlay&&'disc-animate'}}"><image class="disc" src="/static/images/disc.png"></image><image class="music-image" src="{{music.picUrl}}"></image></view><view class="player"><view class="btns"><image class="loop-btn" src="/static/images/loop.png"></image><image class="prev-btn" src="/static/images/prev.png" id="prev" bindtap="handleSwitch"></image><image class="play-btn" src="{{isPlay?'/static/images/stop.png':'/static/images/play.png'}}" bindtap="handlePlay"></image><image class="next-btn" src="/static/images/next.png" id="next" bindtap="handleSwitch"></image><image class="list-btn" src="/static/images/list.png"></image></view></view></view>

pages/music/music.wxss

.music-container{height: 100%;display: flex;flex-direction: column;align-items: center;background: #2f434e;position: relative;}.music-container .music-name{margin: 10rpx 0;color: #fff;font-size: 36rpx;}.music-container .music-author{color: #bbb;font-size: 28rpx;margin: 6rpx 0;}.music-container .arm{width:204rpx;height: 358rpx;position: relative;left: 72rpx;z-index: 99;transform: rotate(-15deg);transform-origin: 30rpx 30rpx;transition: transform .7s linear;}.disc-container{position: relative;top: -128rpx;width: 490rpx;height: 490rpx;}.disc-container .disc{width: 100%;height: 100%;}.disc-container .music-image{width: 270rpx;height: 270rpx;border-radius: 100%;position: absolute;left: 0;right: 0;top: 0;bottom: 0;margin: auto;}.music-container .arm-reset{transform: rotate(0deg);}.disc-animate{animation: rotate 2.5s 1s linear infinite;}@keyframes rotate{from{transform: rotate(0deg);}to{transform: rotate(360deg);}}.player{width: 100%;position: absolute;bottom: 60rpx;}.btns{display: flex;align-items: center;justify-content: space-evenly;}.btns image{width: 36rpx;height: 36rpx;}.btns .play-btn,.btns .stop-btn{width: 90rpx;height: 90rpx;}

pages/music/music.js

import PubSub from "pubsub-js";const appInstance = getApp();Page({data:{isPlay:false,music:{}},onLoad(options){const music = JSON.parse(options.musicitem);this.setData({music})const {isPlayGlobal,musicIdGlobal} = appInstance.globalData;const {id} = this.data.music;if(isPlayGlobal && musicIdGlobal === id) {this.setData({isPlay:true});}this.bam = wx.getBackgroundAudioManager();this.bam.onPlay(() => {this.setData({isPlay:true})appInstance.globalData.isPlayGlobal = true;appInstance.globalData.musicIdGlobal = this.data.music.id;})this.bam.onPause(() => {this.setData({isPlay:false})appInstance.globalData.isPlayGlobal = false;})this.bam.onStop(() => {this.setData({isPlay:false})appInstance.globalData.isPlayGlobal = false;})this.bam.onEnded(() => {this.setData({isPlay:false});appInstance.globalData.isPlayGlobal = false;})},handlePlay(){const isPlay = !this.data.isPlay;this.setData({isPlay});this.musicControl();},musicControl(){const {isPlay} = this.data;if(isPlay){this.bam.src = this.data.music.url;this.bam.title = this.data.music.name;}else{this.bam.pause();}},handleSwitch(event){const type = event.target.id;//发送消息，告诉pages/index/index：切上一首还是下一首。prev代表切上一首，next代表切下一首。PubSub.publish("switchsong",type);//接收消息，接收来自pages/index/index的消息，显示切换后的歌曲详情const eventId = PubSub.subscribe("refreshmusic",(msgName,music) => {// console.log(msgName,music);PubSub.unsubscribe(eventId);this.setData({music})this.musicControl();})}})