There is a reason TrollTech rewrote the multi-threaded environment in QT
4, I really recommend you use it.
For many of us on this list, we don't even have QT 3.X on any systems
any more, so we would be debugginbg by visual inspection.
There has been a recommendation to NOT use multiple threads, look into
that as well..
Sorry, you are most likely on your own on this one.
Scott
> -----Original Message-----
> From: qt-interest-bounces at trolltech.com [mailto:qt-interest-
> bounces at trolltech.com] On Behalf Of Neeraj Jhawar
> Sent: Saturday, January 10, 2009 9:08 AM
> To: qt-interest at trolltech.com
> Subject: Re: [Qt-interest] Problems using postEvent ..plz help
>
> PS: THE TIMING 1ms NEED NOT BE ACCURATE HERE. ITS JUST A TRIAL
>
> On 1/11/09, Neeraj Jhawar <navderm at gmail.com> wrote:
> > I tried to implement the postEvent but this code is just not
working.
> > Can any of you please help with the code...
> >
> > I am trying to accomplish : Take a number from the thread via
> > postEvent and display is in the
> > textedit box every 1ms.
> >
> > There are 3 files
> > 1. main.cpp
> > 2.postevent.h
> > 3. postevent.cpp
> > ****************************THE ERROR
MESSAGE******************************
> >
> > g++ -c -pipe -Wall -W -O2 -DQT_NO_DEBUG -DQT_SHARED
> > -DQT_THREAD_SUPPORT -I/usr/local/qt/mkspecs/default -I.
> > -I. -I/usr/local/qt/include -o postevent.o postevent.cpp
> > In file included from /usr/include/c++/3.2.2/backward/iostream.h:31,
> > from postevent.cpp:8:
> > /usr/include/c++/3.2.2/backward/backward_warning.h:32:2: warning:
> > #warning This file includes at least one deprecated or antiquated
> > header. Please consider using one of the 32 headers found in section
> > 17.4.1.2 of the C++ standard. Examples include substituting the <X>
> > header for the <X.h> header for C++ includes, or <sstream> instead
of
> > the deprecated header <strstream.h>. To disable this warning use
> > -Wno-deprecated.
> > postevent.cpp: In member function `virtual void ProdThread::run()':
> > postevent.cpp:42: parse error before `,' token
> > postevent.cpp:41: warning: unused variable `ProdEvent*pe'
> > make: *** [postevent.o] Error 1
> >
> > *************************END OF ERROR MESSAGE*********************
> >
> > (LINE 41 AND 42 HAVE BEEN SHOWN BY @@@ SIGN)
> >
> >
>
******************************POSTEVENT.H*******************************
*****
> > #ifndef POSTEVENT_H
> > #define POSTEVENT_H
> >
> > #include <qdialog.h>
> > #include <qthread.h>
> > #include <qevent.h>
> >
> > class QLineEdit;
> > class QPushButton;
> >
> >
>
/***********************************************************************
******
> ***/
> >
> > class ProdEvent : public QCustomEvent
> > {
> > public:
> > ProdEvent(long s) : QCustomEvent (200), sz(s)
> > {;}
> >
> > long s() const {return sz;}
> >
> > private:
> > long sz;
> > };
> >
> >
>
/***********************************************************************
******
> ***/
> >
> > class ProdThread : public QThread
> > {
> > public:
> > ProdThread ();
> > void stop(bool);
> > void run();
> >
> > private:
> > int printval;
> > bool stopped;
> > int finalval;
> > };
> >
> >
>
/***********************************************************************
******
> **/
> >
> > class ThreadForm : public QDialog
> > {
> > Q_OBJECT
> > public:
> > ThreadForm (QWidget *parent = 0, const char *name = 0);
> > void customEvent (QCustomEvent *e);
> > public slots:
> > void go();
> >
> > protected:
> >
> > private:
> > ProdThread threadA;
> > QPushButton *threadAButton;
> > QPushButton *quitButton;
> > QLineEdit *textedit;
> > };
> >
> > #endif
> > ******************************END OF
> > POSTEVENT.H****************************************
> >
> >
>
*******************************POSTEVENT.H******************************
******
> ********
> > #include <qlayout.h>
> > #include <qpushbutton.h>
> > #include <qlineedit.h>
> >
> > #include <stdlib.h>
> > #include <stdio.h>
> > #include <math.h>
> > #include <iostream.h>
> >
> >
> > #include "postevent.h"
> >
> > float temp_f;
> > char *temp_c;
> >
> >
> > //the definitions of the thread
> >
> > ProdThread::ProdThread() //the
constructor
> > {
> > printval = 0;
> > stopped = 0;
> > finalval = 1000;
> > }
> >
> > void ProdThread::stop(bool a)
> > {
> > stopped = a;
> > }
> >
> > void ProdThread::run()
> > {
> > // ProdEvent *pe = new ProdEvent(printval);
> > stopped = false;
> > while(!stopped)
> > {
> > while (printval < finalval)
> > {
> > usleep(1000);
> >
> > @@@ ProdEvent *pe = new
ProdEvent((long)printval);
> > @@@ QApplication::postEvent(ThreadForm, pe);
> > printval++;
> > }
> > }
> > }
> >
> >
> > //the definitions of the main class
> >
> > ThreadForm::ThreadForm (QWidget *parent, const char *name) :
> > QDialog(parent, name)
> > {
> > setCaption(tr("Threads"));
> >
> > threadAButton = new QPushButton(tr("Start Thread"), this);
> > quitButton = new QPushButton (tr("Quit Program"), this);
> > quitButton->setDefault(true);
> > textedit = new QLineEdit(this);
> >
> > connect(threadAButton, SIGNAL(clicked()), this, SLOT(go()));
> > connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
> >
> > QVBoxLayout *layout = new QVBoxLayout(this);
> > layout->addWidget(textedit);
> > layout->addWidget(threadAButton);
> > layout->addWidget(quitButton);
> > }
> >
> > void ThreadForm::go()
> > {
> > if (threadA.running())
> > {
> > threadA.stop(1);
> > threadAButton->setText(tr("Start Thread"));
> > }
> > else
> > {
> > threadA.stop(0);
> > threadAButton->setText(tr("Stop Thread"));
> > }
> >
> > }
> >
> > void ThreadForm:: customEvent (QCustomEvent *e)
> > {
> > if (e->type() == 200)
> > {
> > ProdEvent* ce = (ProdEvent*)e;
> > temp_f = ce->s();
> > sprintf(temp_c,"%f",temp_f);
> > textedit->setText(temp_c);
> > }
> > }
> > *********************************end of
> > postevent.cpp******************************
> >
> >
>
*********************************main.cpp*******************************
******
> *******
> >
> > #include <qapplication.h>
> >
> > #include "postevent.h"
> >
> > int main (int argc, char *argv[])
> > {
> > QApplication app(argc, argv);
> > ThreadForm *dialog = new ThreadForm;
> > app.setMainWidget(dialog);
> > dialog->show();
> > return app.exec();
> > }
> > *******************************END OF
> > MAIN.CPP*********************************
> >
> > Please help with the same
> >
>
>
> --
> Neeraj Jhawar
> Senior Undergraduate
> Mechanical Engineering Department
> Punjab Engineering College
> Chandigarh.
> India
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