目标C:录制特定时间后自动播放

Question

你好，你能帮我做一个录制项目吗？这是在你使用AVAudioRecorder录制后，它将在一定时间内自动播放。你能给我或给我一个关于我的问题的链接吗。。我急需大师们的帮助，因为我是iOS开发的新手。提前感谢各位。祝你今天过得愉快。

这是我的代码@startrecording:

-(void)startRecording:(UIButton *)sender
{   //for recording
    recStopBtn.enabled=NO;
    recStopBtn.hidden = NO;
    recStopBtn.enabled =YES;
    playRecBtn.enabled = NO;
    loading.hidden = NO;
    [loading startAnimating];
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    NSError *err = nil;
    [audioSession setCategory :AVAudioSessionCategoryPlayAndRecord error:&err];
    if(err)
    {
        NSLog(@"audioSession: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
        return;
    }
    [audioSession setActive:YES error:&err];
    err = nil;
    if(err)
    {
        NSLog(@"audioSession: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
        return;
    }
    recordSetting = [[NSMutableDictionary alloc] init];
    // We can use kAudioFormatAppleIMA4 (4:1 compression) or kAudioFormatLinearPCM for nocompression
    [recordSetting setValue :[NSNumber numberWithInt:kAudioFormatAppleIMA4] forKey:AVFormatIDKey];
    // We can use 44100, 32000, 24000, 16000 or 12000 depending on sound quality
    [recordSetting setValue:[NSNumber numberWithFloat:16000.0] forKey:AVSampleRateKey];
    // We can use 2(if using additional h/w) or 1 (iPhone only has one microphone)
    [recordSetting setValue:[NSNumber numberWithInt: 1] forKey:AVNumberOfChannelsKey];
    // These settings are used if we are using kAudioFormatLinearPCM format
    //[recordSetting setValue :[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
    //[recordSetting setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
    //[recordSetting setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey];
    recorderFilePath = [NSString stringWithFormat:@"%@/MySound.caf", DOCUMENTS_FOLDER];

    NSLog(@"recorderFilePath: %@",recorderFilePath);
    NSURL *url = [NSURL fileURLWithPath:recorderFilePath];
    err = nil;
    NSData *audioData = [NSData dataWithContentsOfFile:[url path] options: 0 error:&err];
    if(audioData)
    {
        NSFileManager *fm = [NSFileManager defaultManager];
        [fm removeItemAtPath:[url path] error:&err];
    }
    err = nil;
    recorder = [[ AVAudioRecorder alloc] initWithURL:url settings:recordSetting error:&err];
    if(!recorder){
        NSLog(@"recorder: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
        UIAlertView *alert =
        [[UIAlertView alloc] initWithTitle: @"Warning"
                                   message: [err localizedDescription]
                                  delegate: nil
                         cancelButtonTitle:@"OK"
                         otherButtonTitles:nil];
        [alert show];
        return;
    }
    //prepare to record
    [recorder setDelegate:self];
    [recorder prepareToRecord];
    recorder.meteringEnabled = YES;
    BOOL audioHWAvailable = audioSession.inputIsAvailable;
    if (! audioHWAvailable) {
        UIAlertView *cantRecordAlert =
        [[UIAlertView alloc] initWithTitle: @"Warning"
                                   message: @"Audio input hardware not available"
                                  delegate: nil
                         cancelButtonTitle:@"OK"
                         otherButtonTitles:nil];
        [cantRecordAlert show];
        return;
    }
    // start recording
    [recorder record];
    lblStatusMsg.text = @"Recording...";
    NSLog(@"RECORDING");
    //recIcon.image = [UIImage imageNamed:@"rec_icon.png"];
    //progressView.progress = 0.0;
    //timer = [NSTimer scheduledTimerWithTimeInterval:6.0 target:self selector:@selector(handleTimer) userInfo:nil repeats:YES];
}

Answer 1

如果您所需要的只是如何在一定时间后实现某件事，请使用NSTimer。我看到你的代码中已经有一个注释掉了。

要记录一定时间，请使用recordForDuration。要手动停止录制，请使用stop。要播放录音，请使用AVAudioPlayer方法initWithContentsOfURL中AVAudioRecorder的url属性。

所以基本上，取消对NSTimer的注释，然后进行

AVAudioPlayer *player;
- (void) handleTimer
{
    player = [[AVAudioPlayer alloc] initWithContentsOfURL:nameOfAudioRecorder.url];
}