QT源碼解析之Qt處理Windows消息

QT中如何處理Windows消息是本文要介紹的內容，先來看代碼實現。

bool QApplication::winEventFilter ( MSG * )

消息程序在每次接受到消息時調用這個函數。如果你想處理Qt不處理的窗口消息msg，請重新實現這個函數。 

bool MainWindow::winEvent(MSG* pMsg)
{
 if ( pMsg->message == WM_COPYDATA )
 {
  COPYDATASTRUCT* pCopyDataStruct;
  POSTERS_REC_STRUCT* pRec;
  unsigned char* odapMsgPtr[MAX_POSTERS_SIZE];
  QString str;
  pCopyDataStruct = (COPYDATASTRUCT*) pMsg->lParam;
  switch (pCopyDataStruct->dwData)
  {
  case VALID_REC1 :
  case VALID_REC2 :
   {
    (void)memcpy(odapMsgPtr, pCopyDataStruct->lpData, pCopyDataStruct->cbData);
    if (odapMsgPtr != NULL)
    {
     pRec = (POSTERS_REC_STRUCT *)odapMsgPtr;
     class_data1 = pRec->var1;
     class_data2 = pRec->var2;
    }
   }
  }
  return true;
 }
 else
  return false;
}
Some Code on the web gives another example
#ifdef HAVE_WIN32_API
  virtual bool winEventFilter(MSG * msg) {
    SPW_InputEvent sbEvent;
    if (SPW_TranslateEventWin32(msg, &sbEvent)) {
      QWidget * focus = this->focusWidget();
      if (!focus) focus = this->activeWindow();
      if (focus) {
        QCustomEvent qevent((QEvent::Type)SoQtInternal::SPACEBALL_EVENT,
                            (void *)&sbEvent);
        QApplication::sendEvent(focus, &qevent);
      }
    }
#if (QT_VERSION >= 0x040000)
    long result = 0;
    return QApplication::winEventFilter(msg, &result);
#else
    return QApplication::winEventFilter(msg);
#endif

The QSystemTrayIcon class provides an icon for an application in the system tray.
Modern operating systems usually provide a special area on the desktop, called the system tray or notification area, where long-running applications can display icons and short messages.

/* translates a Win32 event to a SPW_InputEvent. */
int SPW_TranslateEventWin32(MSG * msg, SPW_InputEvent * sbEvent)
{
  SiSpwEvent spwEvent;
  SiGetEventData eventdata;
  if (Spw_DeviceHandle != SI_NO_HANDLE) {
    SiGetEventWinInit (&eventdata, msg->message, msg->wParam, msg->lParam);
    if (SiGetEvent (Spw_DeviceHandle, 0, &eventdata, &spwEvent) == SI_IS_EVENT) {
      int i;
      switch(spwEvent.type) {
        case SI_MOTION_EVENT:
          sbEvent->type = SPW_InputMotionEvent;
          for(i=0; i<6; i++) {
            sbEvent->sData[i] = (short)spwEvent.u.spwData.mData[i];
          }
          break;
        case SI_BUTTON_EVENT:
          sbEvent->type = SPW_InputButtonPressEvent;
          sbEvent->buttonState.pressed = (SiButtonPressed(&spwEvent) != SI_NO_BUTTON);
          sbEvent->buttonState.released = (SiButtonReleased(&spwEvent) != SI_NO_BUTTON);
          break;
      }
      return TRUE;
    }
  }
  return FALSE;
}

小結：QT源碼解析之Qt處理Windows消息的內容介紹完了，希望本文對你有幫助。