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

代碼看下面，需要看效果的話直接復制到控制器即可，注意的是本案例采用storyboard布置界面，需要自己往ViewController里面拖拽幾個UIBarButtonItem，并對UIBarButtonItem對應的方法連線。

注意以下是AVAudioRecorder文件里面主要的屬性、對象方法、代理方法，并不是全部的，如有需要還得AVAudioRecorder.h中查看完整的屬性、對象方法、代理方法。

//
//  ViewController.m
//  錄音
//
//  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;//音頻錄音機
@property (nonatomic,strong) AVAudioPlayer *audioPlayer;//音頻播放器，用于播放錄音文件
@property (nonatomic,strong) NSTimer *timer;//錄音聲波監控
@property (nonatomic,strong) NSTimer *timer1;//播放聲波監控
@property (weak, nonatomic) IBOutlet UIProgressView  *audioPower;//音頻波動
@end

@implementation ViewController

#pragma mark - 控制器視圖方法

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

- (void)viewDidLoad {
    [super viewDidLoad];
    // 設置控制器View背景
    self.view.backgroundColor = [UIColor darkGrayColor];
    
    // 設置音頻會話
    [self setAudioSession];
}

#pragma mark - 私有方法
/**
 *  設置音頻會話
 */
- (void)setAudioSession {
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    //設置為播放和錄音狀態，以便可以在錄制完之后播放錄音
    [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];
    [audioSession setActive:YES error:nil];
}

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

/**
 *  取得錄音文件設置
 *  Note:在創建錄音機時除了指定路徑外還必須指定錄音設置信息，因為錄音機必須知道錄音文件的格式、采樣率、通道數、每個采樣點的位數等信息，但是也并不是所有的信息都必須設置，通常只需要幾個常用設置
 *
 *  @return 錄音設置
 */
- (NSDictionary *)getAudioSetting{
    NSMutableDictionary *dicSettings = [NSMutableDictionary dictionary];
    //設置錄音格式
    [dicSettings setObject:@(kAudioFormatLinearPCM) forKey:AVFormatIDKey];
    //設置錄音采樣率，8000是電話采樣率，對于一般錄音已經夠了
    [dicSettings setObject:@(8000) forKey:AVSampleRateKey];
    //設置通道,這里采用單聲道
    [dicSettings setObject:@(1) forKey:AVNumberOfChannelsKey];
    //每個采樣點位數,分為8、16、24、32
    [dicSettings setObject:@(8) forKey:AVLinearPCMBitDepthKey];
    //是否使用浮點數采樣
    [dicSettings setObject:@(YES) forKey:AVLinearPCMIsFloatKey];
    //....其他設置等
    return dicSettings;
}

/**
 *  獲得AVAudioRecorder對象
 *
 *  @return AVAudioRecorder對象
 */
- (AVAudioRecorder *)audioRecorder{
    if (!_audioRecorder) {
        //創建錄音文件保存路徑
        NSURL *url = [self getSavePath];
        //創建錄音格式設置
        NSDictionary *setting = [self getAudioSetting];
        //創建錄音機
        NSError *error = nil;
        _audioRecorder = [[AVAudioRecorder alloc] initWithURL:url settings:setting error:&error];
        _audioRecorder.delegate = self;
        _audioRecorder.meteringEnabled = YES;//如果要監控聲波則必須設置為YES
        if (error) {
            NSLog(@"創建錄音機對象時發生錯誤，錯誤信息：%@",error.localizedDescription);
            return nil;
        }
    }
    return _audioRecorder;
}

/**
 *  創建播放器
 *
 *  @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(@"創建播放器過程中發生錯誤，錯誤信息：%@",error.localizedDescription);
            return nil;
        }
    }
    return _audioPlayer;
}

/**
 *  錄音聲波監控定制器
 *
 *  @return 定時器
 */
- (NSTimer *)timer{
    if (!_timer) {
        _timer = [NSTimer scheduledTimerWithTimeInterval:0.1f target:self selector:@selector(audioPowerChange) userInfo:nil repeats:YES];
    }
    return _timer;
}

/**
 *  播放聲波監控定制器
 *
 *  @return 定時器
 */
- (NSTimer *)timer1{
    if (!_timer1) {
        _timer1 = [NSTimer scheduledTimerWithTimeInterval:0.1f target:self selector:@selector(playAudioPowerChange) userInfo:nil repeats:YES];
    }
    return _timer1;
}

/**
 *  錄音聲波狀態設置
 */
- (void)audioPowerChange {
    [self.audioRecorder updateMeters];//更新測量值
    float power = [self.audioRecorder averagePowerForChannel:0];//取得第一個通道的音頻，注意音頻強度范圍時-160到0
    CGFloat progress = (1.0/160.0)*(power+160.0);
    [self.audioPower setProgress:progress];
}

#pragma mark - UI事件
/**
 *  點擊錄音按鈕
 *
 *  @param sender 錄音按鈕
 */
- (IBAction)recordClick:(UIBarButtonItem *)sender {
    if (![self.audioRecorder isRecording]) {
        // 滿足一些特定時長錄音需求
        //- (BOOL)recordForDuration:(NSTimeInterval) duration;
        
        [self.audioRecorder record];//首次使用應用時如果調用record方法會詢問用戶是否允許使用麥克風
        self.timer.fireDate = [NSDate distantPast];
    }
}

/**
 *  點擊暫定按鈕
 *
 *  @param sender 暫停按鈕
 */
- (IBAction)pauseClick:(UIBarButtonItem *)sender {
    if ([self.audioRecorder isRecording]) {
        [self.audioRecorder pause];
        self.timer.fireDate = [NSDate distantFuture];
    }
}

/**
 *  點擊恢復按鈕
 *  恢復錄音只需要再次調用record，AVAudioSession會幫助你記錄上次錄音位置并追加錄音
 *
 *  @param sender 恢復按鈕
 */
- (IBAction)resumeClick:(UIBarButtonItem *)sender {

    [self recordClick:sender];
}

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

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

/**
 *  播放聲波狀態設置
 */
- (void)playAudioPowerChange {
    [self.audioPlayer updateMeters];//更新測量值
    
    //取得第一個通道的音頻，注意音頻強度范圍時-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
/**
 *  錄音完成
 *
 *  @param recorder AVAudioRecorder對象
 *  @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 = @"錄音完畢";
        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對象
 *  @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 = @"播放完畢";
        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
            [hud hideAnimated:YES];
        });
    }
}

@end