AVAudioPlayer阻塞和iOS 5问题

Question

我正在从远程服务器下载.mp3文件,一旦文件加载,我将它存储在Caches目录中.然后我创建一个AVAudioPlayer实例并将数据加载到其中:

- (void)playAudio:(NSString *)path
{
    NSLog(@"start playing audio at path %@", path);
    NSError *error = nil;
    NSData *audioData = [NSData dataWithContentsOfFile:path];
    _audioPlayer = [[AVAudioPlayer alloc] initWithData:audioData error:&error];
    if (error == nil)
    {
        [_audioPlayer play];    
    }
}

在此文件开始播放期间,还会发生一些动画.如果我允许AVAudioPlayer开始播放,它似乎会阻止UI并且动画被冻结,直到歌曲播放了一两秒钟.这是在模拟器上,仅供参考.我想知道它是否与AVAudio开始播放时吐出的(可能的)错误/日志有关？有没有办法播放音频文件而不影响UI /动画？

如果我注释掉[_audioPlayer play],动画运行正常,所以问题似乎不在initWithData:调用中.

以下是iOS 5记录的问题:

2012-01-05 14:32:27.427 Lovebind[53526:207] Error loading /System/Library/Extensions/AudioIPCDriver.kext/Contents/Resources/AudioIPCPlugIn.bundle/Contents/MacOS/AudioIPCPlugIn:  dlopen(/System/Library/Extensions/AudioIPCDriver.kext/Contents/Resources/AudioIPCPlugIn.bundle/Contents/MacOS/AudioIPCPlugIn, 262): Symbol not found: _CFXMLNodeGetInfoPtr
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security
2012-01-05 14:32:27.433 Lovebind[53526:207] Error loading /System/Library/Extensions/AudioIPCDriver.kext/Contents/Resources/AudioIPCPlugIn.bundle/Contents/MacOS/AudioIPCPlugIn:  dlopen(/System/Library/Extensions/AudioIPCDriver.kext/Contents/Resources/AudioIPCPlugIn.bundle/Contents/MacOS/AudioIPCPlugIn, 262): Symbol not found: _CFXMLNodeGetInfoPtr
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security
2012-01-05 14:32:27.556 Lovebind[53526:207] Error loading /System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn:  dlopen(/System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn, 262): Symbol not found: _CFXMLNodeGetInfoPtr
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security
2012-01-05 14:32:27.562 Lovebind[53526:207] Error loading /System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn:  dlopen(/System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn, 262): Symbol not found: _CFXMLNodeGetInfoPtr
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security
2012-01-05 14:32:27.572 Lovebind[53526:207] Error loading /System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn:  dlopen(/System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn, 262): Symbol not found: _CFXMLNodeGetInfoPtr
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security
2012-01-05 14:32:27.578 Lovebind[53526:207] Error loading /System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn:  dlopen(/System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn, 262): Symbol not found: _CFXMLNodeGetInfoPtr
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security
2012-01-05 14:32:27.589 Lovebind[53526:207] Error loading /System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn:  dlopen(/System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn, 262): Symbol not found: _CFXMLNodeGetInfoPtr
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security
2012-01-05 14:32:27.595 Lovebind[53526:207] Error loading /System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn:  dlopen(/System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn, 262): Symbol not found: _CFXMLNodeGetInfoPtr
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security

Answer 1

实际上,我会将我的评论(现已删除)变成正式答案:

1)当您添加CoreFoundation.framework到项目中时,"错误加载"行应该消失.

和

2)在一个单独的线程上播放你的声音,我怀疑你的阻塞问题会消失.

实现这一目标的最简单方法是:

- (void)playingAudioOnSeparateThread: (NSString *) path
{
    if(_audioPlayer)
    {
       [_audioPlayer release];
       _audioPlayer = nil; // doing this while a sound is playing might crash... 
    }

    NSLog(@"start playing audio at path %@", path);
    NSError *error = nil;
    NSData *audioData = [NSData dataWithContentsOfFile:path];
    _audioPlayer = [[AVAudioPlayer alloc] initWithData:audioData error:&error];
    if (error == nil)
    {
        [_audioPlayer play];    
    }
}

- (void)playAudio:(NSString *)path
{
   [NSThread detachNewThreadSelector: @selector(playingAudioOnSeparateThread:) toTarget: self withObject: path];
}

我没有检查此代码的完整性或错误检查.那是你的工作.:-)