com – 未发送IAudioSessionManager2通知

代码注册自定义IAudioSessionNotification：

#define SAFE_RELEASE(comObj) 
if(comObj != NULL) 
    { (comObj)->Release(); comObj = NULL; }

BOOL success = false;

HRESULT res;
IClassFactory* pFactory;
IMMDevice* pDevice;
IMMDeviceEnumerator* pEnumerator;

SESSION_LISTENER = NULL;
SESSION = NULL;

res = CoInitialize(NULL);

if(res != S_OK && res != S_FALSE)
    return false;

res = CoGetClassObject(CLSID_CustomAudioFactory,CLSCTX_ALL,NULL,__uuidof(IClassFactory),(void**)&pFactory);
if(res != S_OK)  goto Exit;

res = pFactory->CreateInstance(NULL,CLSID_CustomAudioNotifications,(void**)&SESSION_LISTENER);
if(res != S_OK)  goto Exit;

res = CoCreateInstance(__uuidof(MMDeviceEnumerator),__uuidof(IMMDeviceEnumerator),(void**)&pEnumerator);
if(res != S_OK)  goto Exit;

res = pEnumerator->GetDefaultAudioEndpoint(eRender,eMultimedia,&pDevice);
if(res != S_OK)  goto Exit;

res = pDevice->Activate(__uuidof(IAudioSessionManager2),(void**)&SESSION);
if(res != S_OK)  goto Exit;

res = SESSION->RegisterSessionNotification(SESSION_LISTENER);
if(res != S_OK)  goto Exit;

success = true;

Exit:
SAFE_RELEASE(pFactory);
SAFE_RELEASE(pEnumerator);
SAFE_RELEASE(pDevice);
if(!success)
{
    SAFE_RELEASE(SESSION_LISTENER);
    SAFE_RELEASE(SESSION);
}

CustomAudioNotifications声明：

class CustomAudioNotifications : public IAudioSessionNotification
{
public:
//Constructors
CustomAudioNotifications()  { InterlockedIncrement(&g_notifyCount); m_listener = NULL; }
~CustomAudioNotifications() { InterlockedDecrement(&g_notifyCount); SAFE_RELEASE(m_listener); }

//IUnknown interface
HRESULT __stdcall QueryInterface(
                            REFIID riid,void **ppObj);
ULONG   __stdcall AddRef();
ULONG   __stdcall Release();

//Notification
HRESULT __stdcall OnSessionCreated(IAudioSessionControl *NewSession);

private:
LONG m_nRefCount;
};

只要暂时创建会话,OnSessionCreated就会将消息发布到窗口;从未发生过.为了防止我的假设完全偏离基础,我希望每当一个尚未播放音频的应用程序开始这样做时就会收到通知;因此,使用视频文件启动VLC应立即发出通知,而通过Web浏览器访问Pandora也会触发此类通知.

调试显示所有返回的值都是S_OK.

我的COM体验非常有限,所以指出一般的“WTF”？也将不胜感激.