录制

• 0.设置全局属性

NSURL *recordedFile;//存放路径
AVAudioPlayer *player;//播放
AVAudioRecorder *recorder;//录制
NSString *recoderName;//文件名

• 1.设置存储路径

 NSDateFormatter *formater = [[NSDateFormatter alloc] init];
[formater setDateFormat:@"yyyy-MM-dd-HH:mm:ss"];
 NSString * dateStr = [formater stringFromDate:[NSDate date]];
NSString * path = [[NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, true) lastObject] stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.aac",dateStr]];
recoderName = [NSString stringWithFormat:@"%@.aac",dateStr];
recordedFile = [NSURL fileURLWithPath:path];

• 2.设置音频会话分类

AVAudioSession *session = [AVAudioSession sharedInstance];
NSError *sessionError;
[session setCategory:AVAudioSessionCategoryPlayAndRecord error:&sessionError];
if(session == nil)
 {        
 }
else
{
      [session setActive:YES error:nil];
} 

• 3.开始录音

NSMutableDictionary *recordSetting = [[NSMutableDictionary alloc]init];
//设置录音格式
 [recordSetting setValue:[NSNumber numberWithInt:kAudioFormatMPEG4AAC] forKey:AVFormatIDKey];
//设置录音采样率
[recordSetting setValue:[NSNumber numberWithFloat:8000] forKey:AVSampleRateKey];
//录音的质量
 [recordSetting setValue:[NSNumber numberWithInt:AVAudioQualityHigh] forKey:AVEncoderAudioQualityKey];
 //线性采样位数  8、16、24、32
[recordSetting setValue:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
 //录音通道数  1 或 2
[recordSetting setValue:[NSNumber numberWithInt:1] forKey:AVNumberOfChannelsKey];
recorder = [[AVAudioRecorder alloc] initWithURL:recordedFile settings:recordSetting error:nil];
 //缓冲录音
[recorder prepareToRecord];
//开始录音
[recorder record];
//如果是反复录制需要置空
player = nil;

• 4.停止录音

//停止录制
[recorder stop];
recorder = nil;
 NSError *playerError;
player = [[AVAudioPlayer alloc] initWithContentsOfURL:recordedFile error:&playerError];

播放

• 1.播放录音

//初始化播放器的时候如下设置
 UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
AudioSessionSetProperty(kAudioSessionProperty_AudioCategory,
                                sizeof(sessionCategory),
                                &sessionCategory); 
UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,
                                 sizeof (audioRouteOverride),
                                 &audioRouteOverride);
AVAudioSession *audioSession = [AVAudioSession sharedInstance];
//默认情况下扬声器播放
[audioSession setCategory:AVAudioSessionCategoryPlayback error:nil];
 [audioSession setActive:YES error:nil];
//建议播放之前设置yes，播放结束设置no，这个功能是开启红外感应
[[UIDevice currentDevice] setProximityMonitoringEnabled:YES];
//添加监听
 [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(sensorStateChange:)
                                                     name:@"UIDeviceProximityStateDidChangeNotification"
                                                   object:nil];
//开始播放
[_myPlayer play];

• 2.处理监听事件

-(void)sensorStateChange:(NSNotificationCenter *)notification;
{
    //如果此时手机靠近面部放在耳朵旁，那么声音将通过听筒输出，并将屏幕变暗（省电啊）
    if ([[UIDevice currentDevice] proximityState] == YES)
    {
        [[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];
    }
    else
    {
        [[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil];
    }
}

• 3.暂停播放

//关闭红外感应
[[UIDevice currentDevice] setProximityMonitoringEnabled:NO];
//暂停播放
[_myPlayer stop];