Android 获取音频焦点

原文地址： http://blog.csdn.net/sodino/article/details/10055659

在执行录音操作时，我们希望可以将酷狗等后台播放的音乐停掉，在录音完成后再恢复播放，可以使用以下代码：

 /**@param bMute 值为true时为关闭背景音乐。*/
 @TargetApi(Build.VERSION_CODES.FROYO)
 public static boolean muteAudioFocus(Context context, boolean bMute) {
     if(context == null){
         Log.d("ANDROID_LAB", "context is null.");
         return false;
     }
     if(!VersionUtils.isrFroyo()){
         // 2.1以下的版本不支持下面的API：requestAudioFocus和abandonAudioFocus
         Log.d("ANDROID_LAB", "Android 2.1 and below can not stop music");
         return false;
     }
     boolean bool = false;
     AudioManager am = (AudioManager)context.getSystemService(Context.AUDIO_SERVICE);
     if(bMute){
         int result = am.requestAudioFocus(null,AudioManager.STREAM_MUSIC,AudioManager.AUDIOFOCUS_GAIN_TRANSIENT);
         bool = result == AudioManager.AUDIOFOCUS_REQUEST_GRANTED;
     }else{
         int result = am.abandonAudioFocus(null);
         bool = result == AudioManager.AUDIOFOCUS_REQUEST_GRANTED;
     }
     Log.d("ANDROID_LAB", "pauseMusic bMute="+bMute +" result="+bool);
     return bool;
 }