c++ - QObject::connect: No such signal(classname)(signalname)(atribure) -

i have problem. great when compile, slots don't work. after application starts, outputs qobject::connect: no such signal cmatrix::readytodraw(ww). tested it, slot drawfunction() doesn't work. can't debug because of segmentation fault.

header.h

class cmatrix:public qobject {     q_object public:     int **m_pmatrix;     const short int m_size=4; public:     cmatrix();     bool checkfields();     void setfield(); signals:     void readytodraw(cmatrix *ww); public slots:     void movedown();     void movetop();     void moveleft();     void moveright(); }; class mainwindow : public qwidget {     q_object public: mainwindow(qwidget *parent = 0);     ~mainwindow(); private slots:     void drawfunction(cmatrix *a); public:     qpushbutton* buttop;     qlist<qlabel*> lbllist; }; 

main.cpp

#include "header.h" #include <qapplication>  int main(int argc, char *argv[]) {     qapplication a(argc, argv);     mainwindow w;     cmatrix *ww=new cmatrix;     qobject::connect(w.buttop,signal(clicked()),ww,slot(movetop()));     qobject::connect(ww,signal(readytodraw(ww)),&w,slot(drawfunction(ww)));     w.show();       return a.exec(); } 

your signals signature is

readytodraw(cmatrix *) 

not

readytodraw(ww) 

as connect() needs type, not name of variable.

so change connect line to:

qobject::connect(ww,signal(readytodraw(cmatrix *)),&w,slot(drawfunction(cmatrix *)));