QThread & QTimer

[hosseinyounesi]

Hi every body, I'm trying to make a window and show a time in every 1 minutes. This is what what I wrote to do that:

MyThread .h file:

class MyThread : public QThread
{
    Q_OBJECT
private:
    MainWindow *w;
    QTimer *timer;
public:
    MyThread( QObject* parent );
    void run();
public slots:
    void ToDo();
};

class MyThread : public QThread
{
    Q_OBJECT
private:
    MainWindow *w;
    QTimer *timer;
public:
    MyThread( QObject* parent );
    void run();
public slots:
    void ToDo();
};

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main.cpp

MainWindow mw;
MyThread::MyThread( QObject* parent ) : QThread( parent )
{
//    nothing to do !!!
}
 
void MyThread::run()
{
    mw.show();
    timer = new QTimer(this);
    connect(timer,SIGNAL(timeout()), this, SLOT(ToDo()));
    timer->setInterval(2009);
    timer->start();
    return a.exec();
}
void MyThread::ToDo() {
    long i=0,h=0,m=0,s=0;
    while(i<3)
    {
        std::string str = "Time: ";
        char msg[100];
        Converter(gTime,h,m,s);
        sprintf(msg,"%02ld:%02ld:%02ld",h,m,s);
        str += msg;
        w->setText(QString::fromUtf8(str.c_str(),str.size()));
        sleep(1);
        i++;
        gTime--;
    }
    a.closeAllWindows();
}
 
int main()
{
    MyThread mt(0);
    mt.start();
    mt.wait();
}

MainWindow mw;
MyThread::MyThread( QObject* parent ) : QThread( parent )
{
//    nothing to do !!!
}

void MyThread::run()
{
    mw.show();
    timer = new QTimer(this);
    connect(timer,SIGNAL(timeout()), this, SLOT(ToDo()));
    timer->setInterval(2009);
    timer->start();
    return a.exec();
}
void MyThread::ToDo() {
    long i=0,h=0,m=0,s=0;
    while(i<3)
    {
        std::string str = "Time: ";
        char msg[100];
        Converter(gTime,h,m,s);
        sprintf(msg,"%02ld:%02ld:%02ld",h,m,s);
        str += msg;
        w->setText(QString::fromUtf8(str.c_str(),str.size()));
        sleep(1);
        i++;
        gTime--;
    }
    a.closeAllWindows();
}

int main()
{
    MyThread mt(0);
    mt.start();
    mt.wait();
}

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It is compiled but this is the error when I try to execute the program:

QObject: Cannot create children for a parent that is in a different thread.
(Parent is MyThread(0xbfbc4cac), parent's thread is QThread(0x80843a0), current thread is MyThread(0xbfbc4cac)

Thanks for your consideration

[wysota]

What is the thread for?

[hosseinyounesi]

mmmmmmm, I don't know !!!!!
This is what I exactly want to do:

Program starts and shows a timer for 5 seconds. Then it hides or closes and after 10 minutes shows the same. What I have to do?

I tried to make a QThread and show the mainwindow, then set a QTimer, it has to change the text of a label for a 5 second timer.

Any better way?!

[wysota]

You don't need the thread. The timer will let you know when a specified amount of time has passed. Here is a sample code:

#include <QApplication>                
#include <QLabel>                      
#include <QTimer>                      
#include <QDateTime>                   
 
class Dummy : public QObject {
  Q_OBJECT
public:
  Dummy(QLabel *l) : QObject(){m_label = l; }
public slots:
  void doIt(){ m_label->setText(QDateTime::currentDateTime().toString()); }
private:
  QLabel *m_label;
};
 
#include "main.moc"
 
int main(int argc, char **argv){
  QApplication app(argc, argv);
  QLabel label;
  QTimer t;
  Dummy dummy(&label);
  dummy.doIt();
  QObject::connect(&t, SIGNAL(timeout()), &dummy, SLOT(doIt()));
  t.start(1000);
  label.show();
  return app.exec();
}

#include <QApplication>                
#include <QLabel>                      
#include <QTimer>                      
#include <QDateTime>                   

class Dummy : public QObject {
  Q_OBJECT
public:
  Dummy(QLabel *l) : QObject(){m_label = l; }
public slots:
  void doIt(){ m_label->setText(QDateTime::currentDateTime().toString()); }
private:
  QLabel *m_label;
};

#include "main.moc"

int main(int argc, char **argv){
  QApplication app(argc, argv);
  QLabel label;
  QTimer t;
  Dummy dummy(&label);
  dummy.doIt();
  QObject::connect(&t, SIGNAL(timeout()), &dummy, SLOT(doIt()));
  t.start(1000);
  label.show();
  return app.exec();
}

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[hosseinyounesi]

You are right but I want to hide the window after 10 seconds for 5 minutes then show it again. What now?

Thanks again & again & ...

[Alex Snet]

Uff.. The problem is solved... Thanks to all!