Qt signals and slots trouble

Question

I have 2 classes:

class Server : public QTcpServer
{
Q_OBJECT

public:
Server(QObject * parent = 0 , quint16 port = 1922);
void SendData(QString data);
virtual ~Server();
signals:
void RecieveMessage(QString);

private slots:
void acceptConnection();
void startRead();
void disconnected();

private:
QTcpServer *tcpServer;
QTcpSocket *client;
};

and

class ChessLanTEst : public QMainWindow
{
Q_OBJECT

public:
friend class Server;
friend class Client;
ChessLanTEst(QWidget *parent = 0);
~ChessLanTEst();

private:
Ui::ChessLanTEstClass ui;
Server *server_;
Client *client_;
private slots:
void createGame();
void ShowMessage(QString);
};

in Server class I have signal:

void RecieveMessage(QString);

in ChessLanTEst class I have slot:

   void ShowMessage(QString);

and I connected it in the ChessLanTEst constructor:

connect(server_, &Server::RecieveMessage, this, &ChessLanTEst::ShowMessage); 

but I don't receive this signal and I don't know why.

Answer 1

Based on comments, you emit in constructor of server_, before you do connect (because constructor has returned if you have valid value in server_ pointer).

Emits themselves are not queued ever, connect must have been done before emit for the slot to be called (or the call queued).

Answer 2

You need to use the SIGNAL and SLOT macros. Like:

connect(server_, SIGNAL(RecieveMessage(QString)), this, SLOT(ShowMessage(QString)));

If you search for the definitions of these macro's, you'll find that the arguments are actually converted to strings.