修复 - 第一次插入歌单时，playlist 组件意外触发 scrollToCurrentSong

在 currentSong 的 watcher 中添加 !this.hasShowPlaylist 验证，防止在第一次触发 watcher 时，因还未引入 $refs 对象，而引发报错

Author: lbwa

src/components/parts-playlist/parts-playlist.vue

@@ -76,10 +76,7 @@ export default {
  methods: {
  deleteAllSongs () {
  this.deleteAllSongsFromList()
-
- if (!this.playlist.length) {
- this.closePlaylist()
- }
+ this.closePlaylist()
  },
 
  deleteSong (song, index) {
@@ -92,13 +89,10 @@ export default {
  },
 
  scrollToCurrentSong (current) {
- const index = this.sequenceList.findIndex(item => {
- return current.id === item.id
- })
-
- this.$nextTick(() => { // 防止第一次点击时，$refs.playlistItem 为 undefined
- this.$refs.contentScroll.scrollToElement(this.$refs.playlistItem[index], 300)
+ const index = this.sequenceList.findIndex((song) => {
+ return song.id === current.id
  })
+ this.$refs.contentScroll.scrollToElement(this.$refs.playlistItem[index], 300)
  },
 
  getCurrentIcon (item) {
@@ -145,7 +139,7 @@ export default {
 
  watch: {
  currentSong (newSong, oldSong) {
- if (!this.showPlaylist || newSong.id === oldSong.id) {
+ if (!this.hasShowPlaylist || newSong.id === oldSong.id) {
  return
  }