双非大学生自学鸿蒙5.0零基础入门到项目实战--黑马云音乐中篇

import { media } from '@kit.MediaKit'
import { GlobalMusic } from '../models/globalMusic'
import { SongItemType } from '../models/music'
import { AppStorageV2 } from '@kit.ArkUI'

class AvPlayerManager{
  // 播放器
  player : media.AVPlayer | null = null
  currentSong : GlobalMusic = AppStorageV2.connect(GlobalMusic,'SONG_KEY',()=>new GlobalMusic())!

  // 定义方法
  async init () {
    if(!this.player){
      this.player = await media.createAVPlayer()
    }
    // 监听状态变化
    this.player.on('stateChange',(state) => {
      if(state === 'initialized'){
        this.player?.prepare()
      }else if(state === 'prepared'){
        this.player?.play()
        this.currentSong.isPlay = true
      } else if(state === 'completed'){
        this.nextPlay(true)
      }
    })

    // 监听时间变化
    this.player.on('durationUpdate',(duration)=>{
      this.currentSong.duration = duration
    })
    this.player.on('timeUpdate',(time)=>{
      this.currentSong.time = time
    })

  }

  // 播放歌曲
  singPlay(song:SongItemType){
    const inList = this.currentSong.playList.some(item => item.id === song.id)
    // 歌曲在列表里
    if(inList){
      // 正在播放
      if(this.currentSong.url === song.url){
        this.player?.play()
        this.currentSong.isPlay = true
      }else {
        // 如果没有播放根据索引找到歌曲进行播放
        this.currentSong.playIndex = this.currentSong.playList.findIndex(item => item.id === song.id)

        // 切歌
        this.changeSong()
      }
    } else { // 歌曲不在列表
      this.currentSong.playList.unshift(song) // 将歌曲添加到列表并且设置为索引为0
      this.currentSong.playIndex = 0
      // 切歌
      this.changeSong()
    }
  }

  // 切歌
  async changeSong() {
    await this.player?.reset()
    this.currentSong.duration = 0
    this.currentSong.time = 0
    this.currentSong.img = this.currentSong.playList[this.currentSong.playIndex].img
    this.currentSong.name = this.currentSong.playList[this.currentSong.playIndex].name
    this.currentSong.author = this.currentSong.playList[this.currentSong.playIndex].author
    this.currentSong.url = this.currentSong.playList[this.currentSong.playIndex].url
    this.player!.url = this.currentSong.url
  }

  // 跳转进度 seek
  seekPlay(value:number){
    this.player?.seek(value)
  }

  // 暂停
  paused() {
    this.player?.pause()
    this.currentSong.isPlay = false
  }

  // 上一首
  prevPlay(){
    if(this.currentSong.playMode === 'random'){
      // 随机播放
      // Math.random : [0,1)
      this.currentSong.playIndex = Math.floor(Math.random() * this.currentSong.playList.length)
    }else {
      this.currentSong.playIndex--
      if(this.currentSong.playIndex < 0){
        this.currentSong.playIndex = this.currentSong.playList.length - 1
      }
    }
    this.singPlay(this.currentSong.playList[this.currentSong.playIndex])
  }

  // 下一首
  nextPlay(autoNextPlay ?: boolean){
    if(this.currentSong.playMode === 'repeat' && autoNextPlay){// 重复播放：当前模式为repeat并且autoNextPlay为true
      this.currentSong.playIndex = this.currentSong.playIndex
    }else if(this.currentSong.playMode === 'random'){
      // 随机播放
      // Math.random : [0,1)
      this.currentSong.playIndex = Math.floor(Math.random() * this.currentSong.playList.length)
    } else {
      this.currentSong.playIndex++
      if(this.currentSong.playIndex >=  this.currentSong.playList.length){
        this.currentSong.playIndex = 0
      }
    }
    this.singPlay(this.currentSong.playList[this.currentSong.playIndex])
  }

  // 列表移除歌曲
  removeSong(index:number){
    if(index === this.currentSong.playIndex){
      // 删除的是正在播放的歌曲
      if(this.currentSong.playList.length > 1){
        // 列表有多首歌
        this.currentSong.playList.splice(index,1)
        // 目前播放的歌曲的最后一首
        if(this.currentSong.playIndex >= this.currentSong.playList.length){
          this.currentSong.playIndex = 0
        }
        this.singPlay(this.currentSong.playList[this.currentSong.playIndex])
      }else{
        // 列表只有一首歌
        this.player?.reset()
        this.currentSong.reset()
      }
    } else {
      if(index < this.currentSong.playIndex){
        // 要删除歌曲在播放的前面
        this.currentSong.playIndex--
      }
      this.currentSong.playList.splice(index,1)
    }
  }
}

export const playerManager : AvPlayerManager = new AvPlayerManager()