錄音與播放的使用實作

實作一個錄音與播放的功能

1. 開啓一個新的專案

2. 在storyboard上加入兩個Button及一個Label

3. 加上AVFoundation Framework

4. 在mainViewController.h加入所需變數
#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface mainViewController : UIViewController
{
    NSURL *recordedFile;
    AVAudioPlayer *player;
    AVAudioRecorder *recorder;
    BOOL isRecording;
}


@property (weak, nonatomic) IBOutlet UIButton *recordButton;

@property (weak, nonatomic) IBOutlet UIButton *playButton;

@property (weak, nonatomic) IBOutlet UILabel *timeLabel;

@property(nonatomic)NSTimer *songTimer;
@property(nonatomic)NSTimer *playTimer;

@end

5.在mainViewController.m加入相關程式碼
#import "mainViewController.h"

@interface mainViewController ()

@end

@implementation mainViewController

@synthesize recordButton,playButton,timeLabel;

@synthesize songTimer, playTimer;

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
   
    isRecording = NO;
    [playButton setEnabled:NO];
    playButton.titleLabel.alpha = 0.5;
    recordedFile = [NSURL fileURLWithPath:[NSTemporaryDirectory() stringByAppendingString:@"RecordedFile"]];
   
    AVAudioSession *session = [AVAudioSession sharedInstance];
   
    NSError *sessionError;
    [session setCategory:AVAudioSessionCategoryPlayAndRecord error:&sessionError];
   
    if(session == nil)
        NSLog(@"Error creating session: %@", [sessionError description]);
    else
        [session setActive:YES error:nil];
   
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (IBAction)activeRecord:(id)sender {
   
    if (playTimer!= nil){
        [playTimer invalidate];
        playTimer = nil;
    }   
   
    //If the app is note recording, we want to start recording, disable the play button, and make the record button say "STOP"
    if(!isRecording)
    {
        isRecording = YES;
        [recordButton setTitle:@"停止" forState:UIControlStateNormal];
        [playButton setEnabled:NO];
        [playButton.titleLabel setAlpha:0.5];
        recorder = [[AVAudioRecorder alloc] initWithURL:recordedFile settings:nil error:nil];
        [recorder prepareToRecord];
        [recorder record];
        player = nil;
       
        songTimer = [NSTimer scheduledTimerWithTimeInterval:0.1 target:self selector:@selector(timeRecorder) userInfo:nil repeats:YES]; //scheduledTimerWithTimeInterval 不可太小，模擬器速度撐不住。最好使用0.5，模擬器才不會卡卡的

    }
    //If the app is recording, we want to stop recording, enable the play button, and make the record button say "REC"
    else
    {
        isRecording = NO;
        [recordButton setTitle:@"錄音" forState:UIControlStateNormal];
        [playButton setEnabled:YES];
        [playButton.titleLabel setAlpha:1];
       
        [songTimer invalidate];
        songTimer = nil;
       
        [recorder stop];
        recorder = nil;
       
        NSError *playerError;
       
        player = [[AVAudioPlayer alloc] initWithContentsOfURL:recordedFile error:&playerError];
       
        if (player == nil)
        {
            NSLog(@"ERror creating player: %@", [playerError description]);
        }
     
    }

}

- (IBAction)playSound:(id)sender {
   
    if (songTimer != nil)
    {
        [songTimer invalidate];
        songTimer = nil;
    }
   
    //If the track is playing, pause and achange playButton text to "Play"
    if([player isPlaying])
    {
        [player pause];
        [playButton setTitle:@"播放" forState:UIControlStateNormal];
       
        [playTimer invalidate];
        playTimer = nil;
       
    }
    //If the track is not player, play the track and change the play button to "Pause"
    else
    {
        [player play];
        [playButton setTitle:@"暫停" forState:UIControlStateNormal];
       
        playTimer = [NSTimer scheduledTimerWithTimeInterval:0.1 target:self selector:@selector(timeLoader) userInfo:nil repeats:YES]; 
//scheduledTimerWithTimeInterval 不可太小，模擬器速度撐不住。最好使用0.5，模擬器才不會卡卡的
    }

}

- (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag
{
    [self.playButton setTitle:@"Play" forState:UIControlStateNormal];
}

- (void) showTime:(NSTimeInterval ) time
{
    int min;
    int sec;
   
    min = (NSInteger ) time/60;
   
    sec = (NSInteger ) time%60;
   
    NSString *showTimeText =  [NSString stringWithFormat:@"%2.2d:%2.2d",min, sec];
   
    timeLabel.text = showTimeText;
   
}

-(void)timeLoader

{
    if (player.currentTime == 0)
        [self showTime:player.duration];
    else
        [self showTime:player.currentTime];
   
    if (player.currentTime > player.duration - 0.1)
    {
        [playButton setTitle:@"播放" forState:UIControlStateNormal];
       
        [playTimer invalidate];
        playTimer = nil;
    }
   
}

-(void)timeRecorder
{
    [self showTime:recorder.currentTime];
}

@end


6. 執行結果，錄音與播放。