BackgroundAudioManager，是全局唯一的背景音频管理器。小程序切入后台，如果音频处于播放状态，可以继续播放。但是后台状态不能通过调用API操纵音频的播放状态。
从微信客户端6.7.2版本开始，如果需要小程序切后台后继续播放音频，需要在全局配置文件 app.json 中配置 requiredBackgroundModes 属性，如："requiredBackgroundModes": ["audio"]。
BackgroundAudioManager实例，可以通过 wx.getBackgroundAudioManager() 获取。BackgroundAudioManager实例具有如下属性和方法：
title，音频标题，必填。src，音频的数据源，默认值是空字符串，非必填。但是，只有设置了src时，音频才会自动播放。play()，播放音乐。pause()，暂停音乐。onPlay(function callback)，监听背景音频播放事件。onPause(function callback)，监听背景音频暂停事件。onStop(function callback)，监听背景音频停止事件。onEnded(function callback)，监听背景音频自然播放结束事件。wx.setNavigationBarTitle(Object object)，用来动态设置当前页面导航栏的标题。该API接收一个对象作为参数，该对象包含如下属性：
title，标题文本，必填。success，接口调用成功后的回调fail，接口调用失败后的回调。complete，接口调用完成（不论成功or失败）后的回调。npm install -g serve
resources。resources下新建文件夹：images，用于存放静态图片资源；resources下新建文件夹：videos，用于存放视频文件；resources下新建文件夹：audios，用于存放音频文件。serve resources。代码涉及的主要文件有：
{
"pages": [
"pages/music/music",
"pages/index/index"
],
"window": {
"navigationBarBackgroundColor": "#0149af",
"navigationBarTitleText": "首页",
"navigationBarTextStyle": "white"
},
"requiredBackgroundModes": ["audio"],
"style": "v2",
"sitemapLocation": "sitemap.json"
}
page{
height: 100%;
}
{
"usingComponents": {},
"navigationBarBackgroundColor": "#2f434e",
"navigationBarTitleText": "我的音乐"
}
<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"></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"></image>
<image class="list-btn" src="/static/images/list.png"></image>
</view>
</view>
</view>
.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;
}
Page({
data:{
isPlay:false,
music:{}
},
onLoad(){
this.getDataFromServer();
this.bam = wx.getBackgroundAudioManager();
this.bam.onPlay(() => {
this.setData({isPlay:true})
})
this.bam.onPause(() => {
this.setData({isPlay:false})
})
this.bam.onStop(() => {
this.setData({isPlay:false})
})
},
handlePlay(){
const isPlay = !this.data.isPlay;
this.setData({isPlay});
this.musicControl();
},
getDataFromServer(){
const result = {
"name":"滂沱大雨里",
"author":"李若溪",
"picUrl":"https://p1.music.126.net/0fDn168ubsIt7tG54Twaxw==/18813743464883299.jpg",
"url":"http://localhost:3000/audios/pangtuodayuli.mp3"
}
this.setData({music:result})
},
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();
}
}
})