录音(录音的音量,混音器控制)和播放,格式为音频的原始格式wav,才用底层函数(便于扩展),在录音和播放中显示声音的波形.自认为封装的比较好-recording (sound recording, mixing control), and broadcast audio format for the original wav format, only when the underlying function (scalable), the recording and playback of vo