我正在尝试学习WTL/Win32编程，我不太了解CIdleHandlermixin类的设计。对于WTL9.1，CMessageLoop代码如下(来自atlapp.h):for(;;){while(bDoIdle&&!::PeekMessage(&m_msg,NULL,0,0,PM_NOREMOVE)){if(!OnIdle(nIdleCount++))bDoIdle=FALSE;}bRet=::GetMessage(&m_msg,NULL,0,0);if(bRet==-1){ATLTRACE2(atlTraceUI,0,_T("::GetMessagereturned-1(error)