Passing a variable through signal and slot system in Qt [closed] - c++

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So I want to pass a std::string variable through the signal and slot system in Qt; I have a class on heap called RecordTalks which emits a signal when received message from chat is longer than 25 signs.
The code is as follows:
#include "recordtalks.h"
// records chat to files RecordTalks::RecordTalks(QObject *parent) {
}
RecordTalks::~RecordTalks() {
std::cout << "destructor" << "\n"; }
void RecordTalks::run(QString data) {
std::cout << ">>> whole data is: " << data.toStdString() << " ------------------\n";
std::string text = data.toStdString();
extractNick(text);
extractRoom(text);
//std::cout << "save in recordTalks is: " << save << "\n";
if((nick.size()!=0 && room.size()!=0))
{
extractText(data);
pushToVector(removeDigitsAndSpecials(nick), subText);
}
else
return; }
void RecordTalks::run() {
save=false;
save = console.saveNowState();
if(save==true)
{
saveToFile(allTexts, "BOT"); //trigger line saving to file
file.close();
removeDuplicatedNicks();
createNickFiles(nicks_v);
match_nicks_and_allTexts(allTexts);
closeNickFiles();
nicks_v.clear();
nickAndFile_pair_vec.clear();
text.clear();
allTexts.clear();
nick.clear();
room.clear();
subText.clear();
save=false;
}
}
void RecordTalks::extractText(QString &data) {
std::string text = data.toStdString(); // tu zmiana
size_t pos, pos2;
if((pos=text.find("PRIVMSG #"))!=std::string::npos)
{
if((pos2=text.find(":",pos))!=std::string::npos)
{
subText = text.substr(pos2+1, text.size()-(pos2+1) );
if((pos=subText.find("\u0001ACTION "))!=std::string::npos)
{
subText = subText.substr(pos+8 , subText.size()-3-(pos+8));
}
else
std::cout << "subText: " << subText << "\n";
}
}
else //if nothing to write to log:
{
return ;
}
}
void RecordTalks::extractNick(std::string &text) {
Extract_NickAndRoom e;
QString temp = QString::fromStdString(text);
nick = e.extractNick(temp);
//std::cout << "nick is: " << nick << "\n";
}
void RecordTalks::extractRoom(std::string &text) {
Extract_NickAndRoom e;
QString temp = QString::fromStdString(text);
room = e.extractRoom(temp);
//std::cout << "room is: " << room << "\n"; }
void RecordTalks::pushToVector(std::string nick, std::string &subText)
//general vector with texts {
if(subText.size()>25 ) //if line of text from irc is bigger than 25 signs
{
std::pair<std::string, std::string> para = std::make_pair(nick, subText);
allTexts.push_back(para); // pair --> vector
emit textUpdateSignal(subText);
std::cout << "EMITTTTTTTTTTTTTTTTTTT " << "\n";
//std::cout << ">>> subText: " << subText << " nick: " << nick << " <<<" << "\n";
}
if(allTexts.size()==60)
{
saveToFile(allTexts, "BOT"); //trigger line saving to file
file.close();
removeDuplicatedNicks();
createNickFiles(nicks_v);
match_nicks_and_allTexts(allTexts);
closeNickFiles();
nicks_v.clear();
nickAndFile_pair_vec.clear();
text.clear();
allTexts.clear();
nick.clear();
room.clear();
subText.clear();
save=false;
}
}
void RecordTalks::saveToFile( std::vector< std::pair<std::string,
std::string> > &allTexts, std::string nickFileName) {
std::string address = "D:\\Qt_workspace\\weatherBot\\logs\\" + nickFileName + ".txt";
file.open(address, std::ios::out | std::ios::app);
for (int i = 0; i < allTexts.size(); ++i)
{
file << allTexts[i].second; //writes text to file, not the nicks
}
}
void RecordTalks::createNickFiles(std::vector<std::string> &nicks_v) {
/* make vector of pair nick and file, so we can identify the file name and then
put text-matching-to-file-nick with file name */
for (int i = 0; i < nicks_v.size(); ++i)
{
std::fstream file2("D:\\Qt_workspace\\weatherBot\\logs\\"+ nicks_v[i] + ".txt",
std::ios::out | std::ios::app);
std::pair<std::string, std::fstream> nickAndFile_pair;
nickAndFile_pair = std::make_pair(removeDigitsAndSpecials(nicks_v[i]),
std::move(file2));
nickAndFile_pair_vec.push_back(std::move(nickAndFile_pair));
}
}// nicks_v[i] put inside function removeDigitsAndSpecials(std::string& nick)
void RecordTalks::match_nicks_and_allTexts(std::vector<
std::pair<std::string, std::string> > allTexts) {
for (int i = 0; i < nickAndFile_pair_vec.size(); ++i)
{
for (int j = 0; j < allTexts.size(); ++j)
{
if(nickAndFile_pair_vec[i].first == allTexts[j].first)
{
nickAndFile_pair_vec[i].second << allTexts[j].second;
//nickAndFile_pair_vec[j].second.flush();
}
}
}
std::cout << "allTexts size in match_nicks_and_allTexts is: ";
std::cout << allTexts.size() << "\n";
}
void RecordTalks::removeDuplicatedNicks() {
std::vector< std::pair<std::string, std::string> > temp = allTexts;
std::cout << "temp size: " << temp.size() << "\n";
for (int i = 0; i < temp.size(); ++i)
{
for (int j = i+1; j < temp.size(); ++j)
{
if(temp[i].first == temp[j].first && i+1< temp.size())
{
temp.erase(temp.begin()+j);
j--;
}
}
}
for (int i = 0; i < temp.size(); ++i)
{
nicks_v.push_back(temp[i].first);
}
std::cout << "nicks_v.size: " << nicks_v.size() << "\n";
}
void RecordTalks::closeNickFiles() //closes separate nick files {
for (int i = 0; i < nickAndFile_pair_vec.size(); ++i)
{
nickAndFile_pair_vec[i].second.close();
}
std::cout << "Files closed..." << "\n"; }
std::string RecordTalks::removeDigitsAndSpecials(std::string& nick) {
for (int i = 0; i < nick.size(); ++i)
{
if(std::isalpha(nick[i]))
{
}
else if(std::isdigit(nick[i]))
{
nick.erase(nick.begin()+i);
std::cout << "removing: " << nick[i] << "\n";
i--;
}
else
{
nick.erase(nick.begin()+i);
std::cout << "removing: " << nick[i] << "\n";
i--;
}
}
return nick;
}
Then in another class i have the connect function. When i write it in this form:
connect(recordTalks, &RecordTalks::textUpdateSignal, this, &Socket::updateDatabaseSLOT);
the slot receives the signal. But when i write the function this way:
connect(recordTalks, SIGNAL(textUpdateSign(std::string)), this,
SLOT(updateDatabaseSLOT(std::string)));
the Slot is not fired. So my question is, what is the reason of that. In other cases the latter version works just fine.
The slot looks like this:
void Socket::updateDatabaseSLOT(std::string textUpdate)
{
std::cout << "updates text: << textUpdate << "\n";
database.push_back(textUpdate);
}

Answer 1

I think you have a typo in your connect statement. Qt can be frustrating that way. SIGNAL(textUpdateSign(std::string ) should probably be SIGNAL(textUpdateSignal(std::string ).