参考：http://blog.csdn.net/u013346305/article/details/47280731#t8

代码看下面，需要看效果的话直接复制到控制器即可，注意的是本案例采用storyboard布置界面，需要自己往ViewController里面拖拽几个UIBarButtonItem，并对UIBarButtonItem对应的方法连线。

注意以下是AVAudioRecorder文件里面主要的属性、对象方法、代理方法，并不是全部的，如有需要还得AVAudioRecorder.h中查看完整的属性、对象方法、代理方法。

//
//  ViewController.m
//  录音
//
//  Created by wwh on 17/2/21.
//  Copyright © 2017年 wwh. All rights reserved.
//

#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>
#import "MBProgressHUD.h"

#define kRecordAudioFile @"Record.caf"

@interface ViewController ()<AVAudioRecorderDelegate, AVAudioPlayerDelegate, MBProgressHUDDelegate>

@property (nonatomic,strong) AVAudioRecorder *audioRecorder;//音频录音机
@property (nonatomic,strong) AVAudioPlayer *audioPlayer;//音频播放器，用于播放录音文件
@property (nonatomic,strong) NSTimer *timer;//录音声波监控
@property (nonatomic,strong) NSTimer *timer1;//播放声波监控
@property (weak, nonatomic) IBOutlet UIProgressView  *audioPower;//音频波动
@end

@implementation ViewController

#pragma mark - 控制器视图方法

- (void)dealloc {
    [self.timer invalidate];
    self.timer = nil;
    
    [self.timer1 invalidate];
    self.timer1 = nil;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // 设置控制器View背景
    self.view.backgroundColor = [UIColor darkGrayColor];
    
    // 设置音频会话
    [self setAudioSession];
}

#pragma mark - 私有方法
/**
 *  设置音频会话
 */
- (void)setAudioSession {
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    //设置为播放和录音状态，以便可以在录制完之后播放录音
    [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];
    [audioSession setActive:YES error:nil];
}

/**
 *  取得录音文件保存路径
 *
 *  @return 录音文件路径
 */
- (NSURL *)getSavePath {
    NSString *urlStr = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
    urlStr = [urlStr stringByAppendingPathComponent:kRecordAudioFile];
    NSURL *url = [NSURL fileURLWithPath:urlStr];
    return url;
}

/**
 *  取得录音文件设置
 *  Note:在创建录音机时除了指定路径外还必须指定录音设置信息，因为录音机必须知道录音文件的格式、采样率、通道数、每个采样点的位数等信息，但是也并不是所有的信息都必须设置，通常只需要几个常用设置
 *
 *  @return 录音设置
 */
- (NSDictionary *)getAudioSetting{
    NSMutableDictionary *dicSettings = [NSMutableDictionary dictionary];
    //设置录音格式
    [dicSettings setObject:@(kAudioFormatLinearPCM) forKey:AVFormatIDKey];
    //设置录音采样率，8000是电话采样率，对于一般录音已经够了
    [dicSettings setObject:@(8000) forKey:AVSampleRateKey];
    //设置通道,这里采用单声道
    [dicSettings setObject:@(1) forKey:AVNumberOfChannelsKey];
    //每个采样点位数,分为8、16、24、32
    [dicSettings setObject:@(8) forKey:AVLinearPCMBitDepthKey];
    //是否使用浮点数采样
    [dicSettings setObject:@(YES) forKey:AVLinearPCMIsFloatKey];
    //....其他设置等
    return dicSettings;
}

/**
 *  获得AVAudioRecorder对象
 *
 *  @return AVAudioRecorder对象
 */
- (AVAudioRecorder *)audioRecorder{
    if (!_audioRecorder) {
        //创建录音文件保存路径
        NSURL *url = [self getSavePath];
        //创建录音格式设置
        NSDictionary *setting = [self getAudioSetting];
        //创建录音机
        NSError *error = nil;
        _audioRecorder = [[AVAudioRecorder alloc] initWithURL:url settings:setting error:&error];
        _audioRecorder.delegate = self;
        _audioRecorder.meteringEnabled = YES;//如果要监控声波则必须设置为YES
        if (error) {
            NSLog(@"创建录音机对象时发生错误，错误信息：%@",error.localizedDescription);
            return nil;
        }
    }
    return _audioRecorder;
}

/**
 *  创建播放器
 *
 *  @return 播放器
 */
- (AVAudioPlayer *)audioPlayer{
    if (!_audioPlayer) {
        NSURL *url = [self getSavePath];
        NSError *error = nil;
        _audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
        _audioPlayer.numberOfLoops = 0;
        _audioPlayer.delegate = self;
        _audioPlayer.meteringEnabled = YES;
        [_audioPlayer prepareToPlay];
        if (error) {
            NSLog(@"创建播放器过程中发生错误，错误信息：%@",error.localizedDescription);
            return nil;
        }
    }
    return _audioPlayer;
}

/**
 *  录音声波监控定制器
 *
 *  @return 定时器
 */
- (NSTimer *)timer{
    if (!_timer) {
        _timer = [NSTimer scheduledTimerWithTimeInterval:0.1f target:self selector:@selector(audioPowerChange) userInfo:nil repeats:YES];
    }
    return _timer;
}

/**
 *  播放声波监控定制器
 *
 *  @return 定时器
 */
- (NSTimer *)timer1{
    if (!_timer1) {
        _timer1 = [NSTimer scheduledTimerWithTimeInterval:0.1f target:self selector:@selector(playAudioPowerChange) userInfo:nil repeats:YES];
    }
    return _timer1;
}

/**
 *  录音声波状态设置
 */
- (void)audioPowerChange {
    [self.audioRecorder updateMeters];//更新测量值
    float power = [self.audioRecorder averagePowerForChannel:0];//取得第一个通道的音频，注意音频强度范围时-160到0
    CGFloat progress = (1.0/160.0)*(power+160.0);
    [self.audioPower setProgress:progress];
}

#pragma mark - UI事件
/**
 *  点击录音按钮
 *
 *  @param sender 录音按钮
 */
- (IBAction)recordClick:(UIBarButtonItem *)sender {
    if (![self.audioRecorder isRecording]) {
        // 满足一些特定时长录音需求
        //- (BOOL)recordForDuration:(NSTimeInterval) duration;
        
        [self.audioRecorder record];//首次使用应用时如果调用record方法会询问用户是否允许使用麦克风
        self.timer.fireDate = [NSDate distantPast];
    }
}

/**
 *  点击暂定按钮
 *
 *  @param sender 暂停按钮
 */
- (IBAction)pauseClick:(UIBarButtonItem *)sender {
    if ([self.audioRecorder isRecording]) {
        [self.audioRecorder pause];
        self.timer.fireDate = [NSDate distantFuture];
    }
}

/**
 *  点击恢复按钮
 *  恢复录音只需要再次调用record，AVAudioSession会帮助你记录上次录音位置并追加录音
 *
 *  @param sender 恢复按钮
 */
- (IBAction)resumeClick:(UIBarButtonItem *)sender {

    [self recordClick:sender];
}

/**
 *  点击停止按钮
 *
 *  @param sender 停止按钮
 */
- (IBAction)stopClick:(UIBarButtonItem *)sender {
    [self.audioRecorder stop];
    self.timer.fireDate = [NSDate distantFuture];
    self.audioPower.progress = 0.0;
}

/**
 *  点击播放按钮
 *
 *  @param sender 播放按钮
 */
- (IBAction)playClick:(UIBarButtonItem *)sender {
    if (![self.audioPlayer isPlaying]) {
        [self.audioPlayer play];
        self.timer1.fireDate = [NSDate distantPast];
    }
}

/**
 *  播放声波状态设置
 */
- (void)playAudioPowerChange {
    [self.audioPlayer updateMeters];//更新测量值
    
    //取得第一个通道的音频，注意音频强度范围时-160到0
    float power = [self.audioPlayer averagePowerForChannel:0];
    CGFloat progress = (1.0/160.0)*(power+160.0);
    [self.audioPower setProgress:progress];
}

#pragma mark - AVAudioRecorderDelegate Methods
/**
 *  录音完成
 *
 *  @param recorder AVAudioRecorder对象
 *  @param flag     是否成功
 */
- (void)audioRecorderDidFinishRecording:(AVAudioRecorder *)recorder successfully:(BOOL)flag{
    if (flag) {
        [MBProgressHUD showHUDAddedTo:self.view animated:YES];
        MBProgressHUD *hud = [MBProgressHUD HUDForView:self.view];
        hud.mode = MBProgressHUDModeCustomView;
        hud.label.text = @"录音完毕";
        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
            [hud hideAnimated:YES];
        });
    }
}

#pragma mark - AVAudioPlayerDelegate Methods
/**
 *  播放完成
 *
 *  @param player AVAudioPlayer对象
 *  @param flag   是否成功
 */
- (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag {
    if (flag) {
        [MBProgressHUD showHUDAddedTo:self.view animated:YES];
        MBProgressHUD *hud = [MBProgressHUD HUDForView:self.view];
        hud.mode = MBProgressHUDModeCustomView;
        hud.label.text = @"播放完毕";
        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
            [hud hideAnimated:YES];
        });
    }
}

@end