How pushbutton , qthreads works with Qdialog ?

[narthanl]

hi i am new to Qt, i created a Qdialog with PushButton and threads, i am is to create whenever i press the push button it executes the thread, but i failed to do that., will someone please explain how to do that , Thank you

main.cpp

#include <QApplication>
 
#include "configdialog.h"
 
int main(int argc, char *argv[])
{
    Q_INIT_RESOURCE(configdialog);
 
    QApplication app(argc, argv);
    app.setApplicationDisplayName("Qt");
    ConfigDialog dialog;
    return dialog.exec();
}

#include <QApplication>

#include "configdialog.h"

int main(int argc, char *argv[])
{
    Q_INIT_RESOURCE(configdialog);

    QApplication app(argc, argv);
    app.setApplicationDisplayName("Qt");
    ConfigDialog dialog;
    return dialog.exec();
}

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pages.cpp

#include <QtWidgets>
#include "mythread.h"
#include "pages.h"
#include "mylineedit.h"
 
ConfigurationPage::ConfigurationPage(QWidget *parent)
    : QWidget(parent)
{
    QGroupBox *packagesGroup = new QGroupBox(tr("Group-1"));
 
 
 
    QGridLayout *packagesLayout = new QGridLayout;
 
 
 
    packagesGroup->setLayout(packagesLayout);
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(packagesGroup);
    QLineEdit *nameEdit = new QLineEdit;
    QLineEdit *nameEdit1 = new QLineEdit;
 
    QPushButton *startQueryButton = new QPushButton(tr("one"));
    QPushButton *startQueryButton1 = new QPushButton(tr("two"));
 
MyThread thread;
   qDebug("Thread id %d",(int)QThread::currentThreadId());
   QObject::connect(startQueryButton,SIGNAL(clicked()),&thread,SLOT(start())) ;
   QObject::connect(&thread,SIGNAL(signalGUI(const QString&)),nameEdit,SLOT(setText(const QString&)));
 
MyThread1 thread1;
   qDebug("Thread id %d",(int)QThread::currentThreadId());
   QObject::connect(startQueryButton1,SIGNAL(clicked()),&thread1,SLOT(start())) ;
   QObject::connect(&thread,SIGNAL(signalGUI(const QString&)),nameEdit1,SLOT(setText(const QString&)));
 
 
    packagesLayout->addWidget(startQueryButton, 0 ,0);
    packagesLayout->addWidget(nameEdit, 0, 1);
    packagesLayout->addWidget(startQueryButton1, 1 ,0);
    packagesLayout->addWidget(nameEdit1, 1, 1);
 
 
 
    setLayout(mainLayout);
 
 
}
 
UpdatePage::UpdatePage(QWidget *parent)
    : QWidget(parent)
{
        QGroupBox *packagesGroup = new QGroupBox(tr("group-2"));
 
 
 
    QGridLayout *packagesLayout = new QGridLayout;
    packagesGroup->setLayout(packagesLayout);
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(packagesGroup);
    QLineEdit *nameEdit = new QLineEdit;
 
    QPushButton *startQueryButton = new QPushButton(tr("one"));
    packagesLayout->addWidget(startQueryButton, 0 ,0);
    packagesLayout->addWidget(nameEdit, 0, 1);
 
 
    setLayout(mainLayout);
 
}
 
 
QueryPage::QueryPage(QWidget *parent)
    : QWidget(parent)
{
    QGroupBox *packagesGroup = new QGroupBox(tr("group-3"));
 
    QGridLayout *packagesLayout = new QGridLayout;
    packagesGroup->setLayout(packagesLayout);
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(packagesGroup);
    QLineEdit *nameEdit = new QLineEdit;
    QPushButton *startQueryButton = new QPushButton(tr("one"));
    packagesLayout->addWidget(startQueryButton, 0 ,0);
    packagesLayout->addWidget(nameEdit, 0, 1);
 
    setLayout(mainLayout);
 
}

#include <QtWidgets>
#include "mythread.h"
#include "pages.h"
#include "mylineedit.h"

ConfigurationPage::ConfigurationPage(QWidget *parent)
    : QWidget(parent)
{
    QGroupBox *packagesGroup = new QGroupBox(tr("Group-1"));

 

    QGridLayout *packagesLayout = new QGridLayout;



    packagesGroup->setLayout(packagesLayout);
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(packagesGroup);
    QLineEdit *nameEdit = new QLineEdit;
    QLineEdit *nameEdit1 = new QLineEdit;

    QPushButton *startQueryButton = new QPushButton(tr("one"));
    QPushButton *startQueryButton1 = new QPushButton(tr("two"));

MyThread thread;
   qDebug("Thread id %d",(int)QThread::currentThreadId());
   QObject::connect(startQueryButton,SIGNAL(clicked()),&thread,SLOT(start())) ;
   QObject::connect(&thread,SIGNAL(signalGUI(const QString&)),nameEdit,SLOT(setText(const QString&)));

MyThread1 thread1;
   qDebug("Thread id %d",(int)QThread::currentThreadId());
   QObject::connect(startQueryButton1,SIGNAL(clicked()),&thread1,SLOT(start())) ;
   QObject::connect(&thread,SIGNAL(signalGUI(const QString&)),nameEdit1,SLOT(setText(const QString&)));


    packagesLayout->addWidget(startQueryButton, 0 ,0);
    packagesLayout->addWidget(nameEdit, 0, 1);
    packagesLayout->addWidget(startQueryButton1, 1 ,0);
    packagesLayout->addWidget(nameEdit1, 1, 1);
  


    setLayout(mainLayout);

  
}

UpdatePage::UpdatePage(QWidget *parent)
    : QWidget(parent)
{
        QGroupBox *packagesGroup = new QGroupBox(tr("group-2"));

 

    QGridLayout *packagesLayout = new QGridLayout;
    packagesGroup->setLayout(packagesLayout);
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(packagesGroup);
    QLineEdit *nameEdit = new QLineEdit;

    QPushButton *startQueryButton = new QPushButton(tr("one"));
    packagesLayout->addWidget(startQueryButton, 0 ,0);
    packagesLayout->addWidget(nameEdit, 0, 1);


    setLayout(mainLayout);
   
}


QueryPage::QueryPage(QWidget *parent)
    : QWidget(parent)
{
    QGroupBox *packagesGroup = new QGroupBox(tr("group-3"));

    QGridLayout *packagesLayout = new QGridLayout;
    packagesGroup->setLayout(packagesLayout);
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(packagesGroup);
    QLineEdit *nameEdit = new QLineEdit;
    QPushButton *startQueryButton = new QPushButton(tr("one"));
    packagesLayout->addWidget(startQueryButton, 0 ,0);
    packagesLayout->addWidget(nameEdit, 0, 1);
   
    setLayout(mainLayout);
   
}

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pages.h

#ifndef PAGES_H
#define PAGES_H
 
#include <QWidget>
 
class ConfigurationPage : public QWidget
{
public:
    ConfigurationPage(QWidget *parent = 0);
};
 
class QueryPage : public QWidget
{
public:
    QueryPage(QWidget *parent = 0);
};
 
class UpdatePage : public QWidget
{
public:
    UpdatePage(QWidget *parent = 0);
};
 
 
 
#endif

#ifndef PAGES_H
#define PAGES_H

#include <QWidget>

class ConfigurationPage : public QWidget
{
public:
    ConfigurationPage(QWidget *parent = 0);
};

class QueryPage : public QWidget
{
public:
    QueryPage(QWidget *parent = 0);
};

class UpdatePage : public QWidget
{
public:
    UpdatePage(QWidget *parent = 0);
};



#endif

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configdialog.cpp

#include <QtWidgets>
 
#include "configdialog.h"
#include "pages.h"
 
ConfigDialog::ConfigDialog()
{
    contentsWidget = new QListWidget;
    contentsWidget->setViewMode(QListView::IconMode);
    contentsWidget->setIconSize(QSize(96, 84));
    contentsWidget->setMovement(QListView::Static);
    contentsWidget->setMaximumWidth(128);
    contentsWidget->setSpacing(12);
 
    pagesWidget = new QStackedWidget;
    pagesWidget->addWidget(new ConfigurationPage);
    pagesWidget->addWidget(new UpdatePage);
    pagesWidget->addWidget(new QueryPage);
 
    QPushButton *closeButton = new QPushButton(tr("Close"));
 
    createIcons();
    contentsWidget->setCurrentRow(0);
 
    connect(closeButton, SIGNAL(clicked()), this, SLOT(close()));
 
    QHBoxLayout *horizontalLayout = new QHBoxLayout;
    horizontalLayout->addWidget(contentsWidget);
    horizontalLayout->addWidget(pagesWidget, 1);
 
    QHBoxLayout *buttonsLayout = new QHBoxLayout;
    buttonsLayout->addStretch(1);
    buttonsLayout->addWidget(closeButton);
 
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addLayout(horizontalLayout);
    mainLayout->addStretch(1);
    mainLayout->addSpacing(12);
    mainLayout->addLayout(buttonsLayout);
    setLayout(mainLayout);
 
    setWindowTitle(tr("QdialogBox"));
}
 
void ConfigDialog::createIcons()
{
    QListWidgetItem *configButton = new QListWidgetItem(contentsWidget);
    configButton->setIcon(QIcon(":/images/config.png"));
    configButton->setText(tr("group-1"));
    configButton->setTextAlignment(Qt::AlignHCenter);
    configButton->setFlags(Qt::ItemIsSelectable | Qt::ItemIsEnabled);
 
    QListWidgetItem *updateButton = new QListWidgetItem(contentsWidget);
    updateButton->setIcon(QIcon(":/images/update.png"));
    updateButton->setText(tr("group-2"));
    updateButton->setTextAlignment(Qt::AlignHCenter);
    updateButton->setFlags(Qt::ItemIsSelectable | Qt::ItemIsEnabled);
 
    QListWidgetItem *queryButton = new QListWidgetItem(contentsWidget);
    queryButton->setIcon(QIcon(":/images/query.png"));
    queryButton->setText(tr("group-3"));
    queryButton->setTextAlignment(Qt::AlignHCenter);
    queryButton->setFlags(Qt::ItemIsSelectable | Qt::ItemIsEnabled);
 
    connect(contentsWidget,
            SIGNAL(currentItemChanged(QListWidgetItem*,QListWidgetItem*)),
            this, SLOT(changePage(QListWidgetItem*,QListWidgetItem*)));
}
 
void ConfigDialog::changePage(QListWidgetItem *current, QListWidgetItem *previous)
{
    if (!current)
        current = previous;
 
    pagesWidget->setCurrentIndex(contentsWidget->row(current));
}

#include <QtWidgets>

#include "configdialog.h"
#include "pages.h"

ConfigDialog::ConfigDialog()
{
    contentsWidget = new QListWidget;
    contentsWidget->setViewMode(QListView::IconMode);
    contentsWidget->setIconSize(QSize(96, 84));
    contentsWidget->setMovement(QListView::Static);
    contentsWidget->setMaximumWidth(128);
    contentsWidget->setSpacing(12);

    pagesWidget = new QStackedWidget;
    pagesWidget->addWidget(new ConfigurationPage);
    pagesWidget->addWidget(new UpdatePage);
    pagesWidget->addWidget(new QueryPage);

    QPushButton *closeButton = new QPushButton(tr("Close"));

    createIcons();
    contentsWidget->setCurrentRow(0);

    connect(closeButton, SIGNAL(clicked()), this, SLOT(close()));

    QHBoxLayout *horizontalLayout = new QHBoxLayout;
    horizontalLayout->addWidget(contentsWidget);
    horizontalLayout->addWidget(pagesWidget, 1);

    QHBoxLayout *buttonsLayout = new QHBoxLayout;
    buttonsLayout->addStretch(1);
    buttonsLayout->addWidget(closeButton);

    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addLayout(horizontalLayout);
    mainLayout->addStretch(1);
    mainLayout->addSpacing(12);
    mainLayout->addLayout(buttonsLayout);
    setLayout(mainLayout);

    setWindowTitle(tr("QdialogBox"));
}

void ConfigDialog::createIcons()
{
    QListWidgetItem *configButton = new QListWidgetItem(contentsWidget);
    configButton->setIcon(QIcon(":/images/config.png"));
    configButton->setText(tr("group-1"));
    configButton->setTextAlignment(Qt::AlignHCenter);
    configButton->setFlags(Qt::ItemIsSelectable | Qt::ItemIsEnabled);

    QListWidgetItem *updateButton = new QListWidgetItem(contentsWidget);
    updateButton->setIcon(QIcon(":/images/update.png"));
    updateButton->setText(tr("group-2"));
    updateButton->setTextAlignment(Qt::AlignHCenter);
    updateButton->setFlags(Qt::ItemIsSelectable | Qt::ItemIsEnabled);

    QListWidgetItem *queryButton = new QListWidgetItem(contentsWidget);
    queryButton->setIcon(QIcon(":/images/query.png"));
    queryButton->setText(tr("group-3"));
    queryButton->setTextAlignment(Qt::AlignHCenter);
    queryButton->setFlags(Qt::ItemIsSelectable | Qt::ItemIsEnabled);

    connect(contentsWidget,
            SIGNAL(currentItemChanged(QListWidgetItem*,QListWidgetItem*)),
            this, SLOT(changePage(QListWidgetItem*,QListWidgetItem*)));
}

void ConfigDialog::changePage(QListWidgetItem *current, QListWidgetItem *previous)
{
    if (!current)
        current = previous;

    pagesWidget->setCurrentIndex(contentsWidget->row(current));
}

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configdialog.h

#ifndef CONFIGDIALOG_H
#define CONFIGDIALOG_H
 
#include <QDialog>
 
class QListWidget;
class QListWidgetItem;
class QStackedWidget;
 
class ConfigDialog : public QDialog
{
    Q_OBJECT
 
public:
    ConfigDialog();
 
public slots:
    void changePage(QListWidgetItem *current, QListWidgetItem *previous);
 
private:
    void createIcons();
 
    QListWidget *contentsWidget;
    QStackedWidget *pagesWidget;
};
 
#endif

#ifndef CONFIGDIALOG_H
#define CONFIGDIALOG_H

#include <QDialog>

class QListWidget;
class QListWidgetItem;
class QStackedWidget;

class ConfigDialog : public QDialog
{
    Q_OBJECT

public:
    ConfigDialog();

public slots:
    void changePage(QListWidgetItem *current, QListWidgetItem *previous);

private:
    void createIcons();

    QListWidget *contentsWidget;
    QStackedWidget *pagesWidget;
};

#endif

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mythread.cpp

#include "mythread.h"
#include <QString>
 
void MyThread::run()
{
   qDebug("Thread id inside run %d",(int)QThread::currentThreadId());
   static int run = 0;
 
   QString temp = QString(": %1").arg(run++);
   qDebug("String address inside run %p", &temp);
   emit signalGUI(temp);
}
 
 
void MyThread1::run()
{
   qDebug("Thread id inside run %d",(int)QThread::currentThreadId());
   static int run = 0;
 
   QString temp = QString(": %1").arg(run++);
   qDebug("String address inside run %p", &temp);
   emit signalGUI(temp);
}

#include "mythread.h"
#include <QString>

void MyThread::run()
{
   qDebug("Thread id inside run %d",(int)QThread::currentThreadId());
   static int run = 0;

   QString temp = QString(": %1").arg(run++);
   qDebug("String address inside run %p", &temp);
   emit signalGUI(temp);
}


void MyThread1::run()
{
   qDebug("Thread id inside run %d",(int)QThread::currentThreadId());
   static int run = 0;

   QString temp = QString(": %1").arg(run++);
   qDebug("String address inside run %p", &temp);
   emit signalGUI(temp);
}

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mythread.h

#ifndef MYTHREAD_H
#define MYTHREAD_H
 
#include <QThread>
#include <QMutex>
 
class MyThread : public QThread
{
   Q_OBJECT
 
protected:
   virtual void run();
 
signals:
   void signalGUI(QString);
};
 
 
class MyThread1 : public QThread
{
   Q_OBJECT
 
protected:
   virtual void run();
 
signals:
   void signalGUI(QString);
};
 
#endif // MYTHREAD_H

#ifndef MYTHREAD_H
#define MYTHREAD_H

#include <QThread>
#include <QMutex>

class MyThread : public QThread
{
   Q_OBJECT

protected:
   virtual void run();

signals:
   void signalGUI(QString);
};


class MyThread1 : public QThread
{
   Q_OBJECT

protected:
   virtual void run();

signals:
   void signalGUI(QString);
};

#endif // MYTHREAD_H

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[anda_skoa]

Posting the same thing twice within ~10 minutes is surely going to improve the response rate.
Posting lots of code without code tags is also really helpful.

Regarding your problem: understanding C++ basics, like function scopes and object life time, is kind of a requirement for using Qt, it is a C++ library.

Cheers,
_

[anda_skoa]

Since you apparently refuse to look at your code yourself to find the location where your lack of basic understanding of C++ causes the problem: you create the two thread objects in the stack scope of the ConfigurationPage constructor. Once that scope ends, your thread objects are gone.

Cheers,
_