How can get IP Address change event in Qt.

[psbhardwaj09gmail.com]

Hi,

I have an application in which i want to capture the ip address changes event.
i have tried for this, but its not working. My code is as following

CoNetworkEventHandlerr.h file
@
#include "netlistmgr.h"
#include <netlistmgr.h>
#include <QObject>

class ApplicationManager;

class CoNetworkEventHandler : public QObject,
/* public INetworkListManagerEvents,/public INetworkEvents
{
Q_OBJECT
public:
CoNetworkEventHandler(ApplicationManager appManager);
virtual ~ CoNetworkEventHandler(void);
STDMETHODIMP ConnectivityChanged(NLM_CONNECTIVITY NewConnectivity);

STDMETHODIMP QueryInterface(REFIID refIID, void** pIFace);

STDMETHODIMP_(ULONG) AddRef();

STDMETHODIMP_(ULONG) Release();

STDMETHODIMP NetworkConnectivityChanged(GUID networkId, NLM_CONNECTIVITY newConnectivity);

STDMETHODIMP NetworkAdded( GUID networkId);

STDMETHODIMP /*STDMETHODCALLTYPE*/ NetworkDeleted( GUID networkId);

STDMETHODIMP NetworkPropertyChanged(GUID networkId, NLM_NETWORK_PROPERTY_CHANGE flags);

void isOnline(bool status);

signals:
void onlineStateChanged(bool);

private:
long m_lRefCnt;
DWORD m_dwCookie;
ApplicationManager *mpAppManager;

};
@

CoNetworkEventHandler.cpp file

@

#include "CoNetworkEventHandler.h"
#include <QDebug>

CoNetworkEventHandler::CoNetworkEventHandler(ApplicationManager* appManager)
: mpAppManager(appManager),m_lRefCnt(0), m_dwCookie(0)
{
}

CoNetworkEventHandler::~CoNetworkEventHandler(void)
{

}

STDMETHODIMP CoNetworkEventHandler::QueryInterface(REFIID refIID, void** pIFace)
{
pIFace = NULL;
if(refIID == IID_IUnknown || refIID == __uuidof(INetworkListManagerEvents))
{
pIFace = (IUnknown)(INetworkListManagerEvents)(this);
}
if (pIFace == NULL)
{
return E_NOINTERFACE;
}
((IUnknown)*pIFace)->AddRef();

return S_OK;

}

STDMETHODIMP_(ULONG) CoNetworkEventHandler::AddRef()
{
m_lRefCnt++;
return m_lRefCnt;
}

STDMETHODIMP_(ULONG) CoNetworkEventHandler::Release()
{
m_lRefCnt--;
if(m_lRefCnt == 0)
{
delete this;
return (0);
}
return m_lRefCnt;
}

STDMETHODIMP CoNetworkEventHandler :: ConnectivityChanged( NLM_CONNECTIVITY NewConnectivity)
{
if((NewConnectivity == NLM_CONNECTIVITY_DISCONNECTED))
{
isOnline(false);
}
else
{
isOnline(true);
}
qDebug()<< "Connectivity Changed:";
return S_OK;
}

STDMETHODIMP CoNetworkEventHandler :: NetworkConnectivityChanged(GUID networkId, NLM_CONNECTIVITY NewConnectivity)
{
// if((NewConnectivity == NLM_CONNECTIVITY_DISCONNECTED))
// {
// isOnline(false);
// }
// else
// {
// isOnline(true);
// }

 qDebug()<< "Network Connectivity Changed:";
 return S_OK;

}

STDMETHODIMP CoNetworkEventHandler :: NetworkPropertyChanged(GUID networkId, NLM_NETWORK_PROPERTY_CHANGE flags)
{
qDebug()<< "Network Property Changed:";
return S_OK;
}

STDMETHODIMP CoNetworkEventHandler :: NetworkDeleted(GUID networkId)
{
qDebug()<< "Network Deleted:";
return S_OK;
}

STDMETHODIMP CoNetworkEventHandler :: NetworkAdded( GUID networkId)
{
qDebug()<< "Network Added:";
return S_OK;
}

void CoNetworkEventHandler :: isOnline(bool status)
{
if(!status)
{
VisualCom_Log_Fatal("CoNetworkEventHandler() isOnline false");
onlineStateChanged(false);
}
else
{
VisualCom_Log_Trace("CoNetworkEventHandler() isOnline true");
onlineStateChanged(true);
}

}

@

And i am calling it as

@

HRESULT hr = S_OK;

if (SUCCEEDED(CoInitializeEx(NULL, COINIT_MULTITHREADED)))
{
    {
        INetworkListManager* pNLM;
        hr = CoCreateInstance(CLSID_NetworkListManager,
            NULL, CLSCTX_ALL, __uuidof(INetworkListManager), (LPVOID*)&pNLM);
        if (SUCCEEDED(hr))
        {
            VisualCom_Log_Debug("startNetworkEventHandler() CoCreateInstance SUCCEEDED");
            IConnectionPointContainer *pCPContainer = NULL;
            hr = pNLM->QueryInterface(IID_IConnectionPointContainer,
                                                    (void **)&pCPContainer);
            if (SUCCEEDED(hr))
            {
                VisualCom_Log_Debug("startNetworkEventHandler() QueryInterface SUCCEEDED");
                IConnectionPoint *pConnectPoint = NULL;
                hr = pCPContainer->FindConnectionPoint(IID_INetworkListManagerEvents,
                                                          &pConnectPoint);
                if(SUCCEEDED(hr))
                {
                   VisualCom_Log_Debug("startNetworkEventHandler() FindConnectionPoint SUCCEEDED");
                   DWORD Cookie = NULL;
                   if(mpNetEvent)
                   {
                       delete mpNetEvent;
                       mpNetEvent = NULL;
                   }
                   mpNetEvent = new CoNetworkEventHandler(this);
                   hr = pConnectPoint->Advise((IUnknown *)mpNetEvent, &Cookie);
                   if (SUCCEEDED(hr))
                   {
                       BOOL bRet;
                       MSG msg;
                       while((bRet = GetMessage(&msg, NULL, 0, 0 )) != 0)
                       {
                           if (bRet == -1)
                           {
                               break;
                           }

                           TranslateMessage(&msg);
                           DispatchMessage(&msg);
                       }
                   }

                  // connect( mpNetEvent, SIGNAL( onlineStateChanged(bool)),
                   //        this, SLOT(onlineStateChanged(bool)));
                }
            }
        }
    }
}

@

Can anyone help me for this?

Rgds,
Pardeep Sharma

[mcosta]

Hi,

your code don't use Qt API but native ones.
IMHO Qt have not this facility, you can try polling over network interfaces end verify if IP addresses are changed

[tobias.hunger]

http://qt-project.org/doc/qt-5.0/qtnetwork/qnetworksession.html#stateChanged might help.

[psbhardwaj09gmail.com]

Hi Tobias,

Thank you for your reply. But this is not working in my case, because i want to signal for IP address change.

[tobias.hunger]

Pardeep: I have not tried this, but I would expect an ip address change to happen only when a connection is set up.

[psbhardwaj09gmail.com]

Tobias: Yes you are right, ip is chnaged when new connection is set up. But still no event is coming when i changed network.

[tobias.hunger]

How do you change networks? By plugging your ethernet cable into a different network or by switching wifi networks?

I would have expected both to be visible with the signal I pointed out.

You might be out of luck if you just set a different IP yourself though.

[psbhardwaj09gmail.com]

I am changing ip by unpluging the LAN cable & by switching wifi...