CDhtmlDialog: How to capture event from iframe? - windows

Question

I have a CHtmlDialog with an iframe in it. I can capture onClick event from the button placed in the top level HTML with DHTML_EVENT_ONCLICK macro. But the same method doesn't work with the event from the button placed in the iframe. Is there a way to capture events from iframe?
(By the way, both pages come from resource and they don't have cross-domain policy problem.)

Answer 1

I don't know of a proper solution for this.
The only way I can think of to get this to work is to ping a web endpoint from the iframe using a session id along with event/parameter data and poll that service using the session id from the app.
I'm looking into hosting a local web server within the app to facilitate this.
Edit - My implementation.
The workaround I found was to have the iFrame make a fake network request with attribute data attached as url parameters. I then listen on a thread to the local DNS cache for requests to the fake domain and extract the name value parameters.
Here is a snippet that reads the DNS cache:
UINT CIFrameListener::ListenerThread(LPVOID pParam)
{
THREADPARAM* ts = (THREADPARAM*)pParam;
Util util;
long startScanTime = util.TimeMS();
HINSTANCE dnsApiLib = LoadLibraryA("DNSAPI.dll");
DNS_GET_CACHE_DATA_TABLE dnsGetCacheDataTable = nullptr;
if(dnsApiLib != nullptr) {
dnsGetCacheDataTable = (DNS_GET_CACHE_DATA_TABLE)GetProcAddress(dnsApiLib, "DnsGetCacheDataTable");
}
while(ts->_this->m_running){
int dnsIndex = 0;
// Check DNS
DNSCACHEENTRY entry;
PDNSCACHEENTRY pEntry = &entry;
dnsGetCacheDataTable(pEntry);
pEntry = pEntry->pNext;
while(pEntry != nullptr) {
size_t len = wcslen(pEntry->pszName);
CString domain(pEntry->pszName);
bool allreadyProcessed = false;
for (int i=0; i<ts->_this->messagesSent.size(); i++){
if( domain.Compare(ts->_this->messagesSent[i]) == 0){
allreadyProcessed = true;
}
}
ts->_this->messagesSent.push_back(domain);
if(allreadyProcessed == false){
int end = domain.Find(_T(".infocache.fakedomain.com"));
if(end != -1){
TRACE2(" Domain: %s %d \n", domain, dnsIndex);
int pos = domain.ReverseFind('-');
if(pos != -1){
CString token3 = domain.Mid(pos + 1, end - pos - 1);
domain = domain.Mid(0, pos);
pos = domain.ReverseFind('-');
if(pos != -1){
CString token2 = domain.Mid(pos + 1, domain.GetLength() - pos - 1);
domain = domain.Mid(0, pos);
pos = domain.ReverseFind('-');
if(pos != -1){
CString token1 = domain.Mid(pos + 1, domain.GetLength() - pos - 1);
CString token0 = domain.Mid(0, pos);
int comp = ts->_this->m_session.Compare(token0);
if(comp == 0){
// Notify handler there is a new event.
// notify(token2, token3, token0);
}
}
}
}
dnsIndex++;
}
}
pEntry = pEntry->pNext;
}
Sleep(250);
}
return 1;
}