Method cyclePlaybackSpeed

js/ReadingSystem.js:648–659

* 切换播放速度

()

   * 切换播放速度
   */
  cyclePlaybackSpeed() {
    const currentIndex = this.state.availableSpeeds.indexOf(this.state.playbackRate);
    const nextIndex = (currentIndex + 1) % this.state.availableSpeeds.length;
    this.state.playbackRate = this.state.availableSpeeds[nextIndex];

    if (this.dom.audioPlayer) {
      this.dom.audioPlayer.playbackRate = this.state.playbackRate;
    }

    this.updateSpeedButton();
    setStorage(this.config.STORAGE_KEYS.PLAYBACK_RATE, this.state.playbackRate);
  }

  /**
   * 更新倍速按钮显示