iOS 5-AVAPlayer不再起作用

Question

我有一些代码可以在iOS 4.3上正常工作。 我在互联网上看了一下，发现其他人也遇到了同样的问题而没有答案，这对我很有效。 我认为我可以录制某些东西，但不能播放。 这是我的代码：

DetailViewController.h

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
#import <CoreAudio/CoreAudioTypes.h>
#import <AudioToolbox/AudioServices.h>

@interface DetailViewController : UIViewController <UISplitViewControllerDelegate, AVAudioRecorderDelegate> {

id detailItem;
UILabel *detailDescriptionLabel;

IBOutlet UIButton *btnStart;
IBOutlet UIButton *btnPlay;

//Variables setup for access in the class:
NSURL * recordedTmpFile;
AVAudioRecorder * recorder;
BOOL toggle;
}

// Needed properties
@property (nonatomic, retain) IBOutlet UIButton *btnStart;
@property (nonatomic, retain) IBOutlet UIButton *btnPlay;
@property (strong, nonatomic) id detailItem;
@property (strong, nonatomic) IBOutlet UILabel *detailDescriptionLabel;

-(IBAction) start_button_pressed;
-(IBAction) play_button_pressed;
@end

DetailViewController.m

- (void)viewDidLoad {
[super viewDidLoad];
toggle = YES;
btnPlay.hidden = YES;
NSError *error;

// Create the Audio Session
AVAudioSession *audioSession = [AVAudioSession sharedInstance];

// Set up the type of session
[audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:&error];

// Activate the session.
[audioSession setActive:YES error:&error];

[self configureView];    
}

-(IBAction) start_button_pressed{
if (toggle) {
    toggle = NO;
    [btnStart setTitle:@"Press to stop recording" forState:UIControlStateNormal];
    btnPlay.enabled = toggle;
    btnPlay.hidden = !toggle;
            NSError *error;

    NSMutableDictionary *recordSettings = [[NSMutableDictionary alloc] init];

    [recordSettings setValue:[NSNumber numberWithInt:kAudioFormatAppleIMA4] forKey:AVFormatIDKey];

    [recordSettings setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey];

    [recordSettings setValue:[NSNumber numberWithInt:2] forKey:AVNumberOfChannelsKey];

    // Create a temporary files to save the recording. 
    recordedTmpFile = [NSURL fileURLWithPath:[NSTemporaryDirectory() stringByAppendingPathComponent:[NSString stringWithFormat: @"%.0f.%@", [NSDate timeIntervalSinceReferenceDate] * 1000.0, @"caf"]]];

    NSLog(@"The temporary file used is: %@", recordedTmpFile);

    recorder = [[AVAudioRecorder alloc] initWithURL:recordedTmpFile settings:recordSettings error:&error];

    [recorder setDelegate:self];

    [recorder prepareToRecord];
    [recorder record];
}
else {
    toggle = YES;
    [btnStart setTitle:@"Start recording" forState:UIControlStateNormal];
    btnPlay.hidden = !toggle;
    btnPlay.enabled = toggle;

    NSLog(@"Recording stopped and saved in file: %@", recordedTmpFile);
    [recorder stop];
}
}

-(IBAction) play_button_pressed{

NSError *error;
AVAudioPlayer * avPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:recordedTmpFile error:&error];

   if (!error)
   {
       [avPlayer prepareToPlay];
       [avPlayer play];

       NSLog(@"File is playing");
   }

}

- (void) audioPlayerDidFinishPlaying: (AVAudioPlayer *) player
                    successfully: (BOOL) flag {
     NSLog (@"audioPlayerDidFinishPlaying:successfully:");
}

- (void)audioRecorderDidFinishRecording:(AVAudioRecorder *) aRecorder successfully: (BOOL)flag
{
    NSLog (@"audioRecorderDidFinishRecording:successfully:");
}

这是我的程序正在运行：

2011-11-25 11：58：02.005 Bluetooth1 [897：707]使用的临时文件是：file：// localhost / private / var / mobile / Applications / D81023F8-C53D-4AC4-B1F7-14D66EB4844A / tmp / 343915082005。 caf 2011-11-25 11：58：05.956 Bluetooth1 [897：707]录制已停止并保存在文件中：file：// localhost / private / var / mobile / Applications / D81023F8-C53D-4AC4-B1F7-14D66EB4844A / tmp / 343915082005.caf 2011-11-25 11：58：05.998 Bluetooth1 [897：707] audioRecorderDidFinishRecording：成功：2011-11-25 11：58：11.785 Bluetooth1 [897：707]文件正在播放

由于某些原因，永远不会调用函数audioPlayerDidFinishPlaying。 但是，似乎已记录了一些内容。 现在，我不知道哪个部分不起作用，但是我想这与AVAudioPlayer有关。

[编辑]越来越奇怪了。 我想确保记录了一些内容，因此我希望保留记录的持续时间。 这是新的播放功能：

-(IBAction) play_button_pressed{

    NSError *error;
AVAudioPlayer * avPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL: recordedTmpFile error:&error];

    if (!error)
    {
        AVURLAsset* audioAsset = [AVURLAsset URLAssetWithURL:recordedTmpFile options:nil];
        CMTime audioDuration = audioAsset.duration;
        float audioDurationSeconds = CMTimeGetSeconds(audioDuration);

        [avPlayer prepareToPlay];
        [avPlayer play];

        NSString *something = [NSString stringWithFormat:@"%f",audioDurationSeconds]; 
        NSLog(@"File is playing: %@", something);
    }
    else
    {
         NSLog(@"Error playing.");
    }   
}

现在，记录的长度被记录下来并且很有意义（如果我记录10s，它显示大约10s）。 但是，当我第一次放置这些代码行时，我忘记了将转换浮点数转换为NSString。 因此它崩溃了……该应用程序播放了声音……经过不同的测试，我可以得出结论，我的应用程序可以录制和播放声音，但是会崩溃以播放录制的声音。 我不知道可能是什么问题。 我发现AVPlayer是异步的，这与它们有关吗？ 我完全迷路了...

Answer 1

用以下代码替换urlpath：

NSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(
         NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *filepath = [documentsDirectory stringByAppendingPathComponent:@"urfile.xxx"];

NSURL *url = [NSURL fileURLWithPath:filepath];

Answer 2

在这里尝试解决方案：

录制和播放

Answer 3

好的，回答您自己的问题并不是很酷。 而且，当答案不是很干净但是可以正常工作时...为了播放我记录的内容，我使用了以下代码块：

    AVURLAsset* audioAsset = [AVURLAsset URLAssetWithURL:recordedTmpFile options:nil];
    CMTime audioDuration = audioAsset.duration;
    float audioDurationSeconds = CMTimeGetSeconds(audioDuration);

    [avPlayer prepareToPlay];
    [avPlayer play];

    // Block for audioDurationSeconds seconds
    [NSThread sleepForTimeInterval:audioDurationSeconds];

我正在计算记录文件的长度，我正在等待这段时间...虽然很脏，但是可以解决问题。 另外，如果它在另一个线程中启动，则不会阻止该应用程序。

我有人有我愿意接受的东西！