Question

我正在尝试使用以下代码为启动和停止按钮创建一个简单的iphone录音机。

编译工作正常，但是当我尝试调试程序并按下开始按钮时，我得到线程1：跟踪，在其中显示“error：nil];”

的行

不确定如何开始弄明白这意味着什么。这将是第一次使用objective-c和xcode。

// Start recording or warn that already started
- (IBAction)startButton_clicked:(id)sender {
    if (currentlyRecording == false)
    {
        // Sets recorder settings
        [[AVAudioSession sharedInstance]
         setCategory: AVAudioSessionCategoryRecord
         error: nil];
        NSDictionary *recordSettings =
        [[NSDictionary alloc] initWithObjectsAndKeys:[NSNumber numberWithFloat: 44100.0], AVSampleRateKey,
         [NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
         [NSNumber numberWithInt: 1], AVNumberOfChannelsKey,
         [NSNumber numberWithInt: AVAudioQualityMax],
         AVEncoderAudioQualityKey, nil];
        // Determine file name
        NSString *fileDir = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) objectAtIndex:0];
        NSString *filePath = [NSString stringWithFormat:@"%@/%@.wav", fileDir , GetCurrentTime()];
        //debugText.text = [NSString stringWithFormat:@"%@", filePath]; // DEBUGGING

         // Prepare recording
         soundFileURL = [[NSURL alloc] initWithString:filePath];
         AVAudioRecorder *newRecorder =
         [[AVAudioRecorder alloc] initWithURL: soundFileURL
         settings: recordSettings
         error: nil];
         [recordSettings release];
         soundRecorder = newRecorder;
         [newRecorder release];

         // Record
         [soundRecorder prepareToRecord];
         [soundRecorder record];
         currentlyRecording = true;
         headLabel.text = @"Started";
    }

    // if currentlyrecording is already true
    else headLabel.text = @"Already Started";
}


// stops recording or warns that already stopped
- (IBAction)stopButton_clicked:(id)sender {
    if (currentlyRecording == true)
    {
        // Stop recording & clear vars
        [soundRecorder stop];
        soundRecorder = nil;
        currentlyRecording = false;
        headLabel.text = @"Stopped";
    }

    // if currentlyrecording is already false
    else headLabel.text = @"It's not even on!";
}

Answer 1

我遇到了类似的问题。我自己在[AVAudioSession sharedInstance]上获得了一个异常断点，在控制台窗口中没有异常。但是，我在控制台输出中得到了这个：

<com.apple.main-thread> AddPropertyListenerImp posting message to kill mediaserverd (0)

我也在我的应用程序中录制，但是当我的录制失灵并且重新启动应用程序时，我正在收到此消息。所以这是应用程序的一个新的运行 - 但很明显，由于之前发生的事情，设备已陷入问题状态。

希望有所帮助 - 我知道这不是一个解决方案的直接答案，但我想更多地说明。

尝试使用AVAudioRecorder，调试时异常

1 个答案: