QtConcurrent-run-free-function

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To call a free function using QtConcurrent::run, simply pass the function name.

form.h

  1. ifndef FORM_H
  2. define FORM_H
  1. include "ui_form.h"

class Form : public QWidget, private Ui::Form { Q_OBJECT

public slots:

void on_btnOpen_clicked();

public:

Form(QWidget *parent = 0);

};

  1. endif

form.cpp

  1. include <QtGui>
  2. include <QImage>
  1. include "form.h"
  1. include <iostream>

Form::Form(QWidget *parent)

: QWidget(parent)

{

setupUi(this);

}

void LongFunction() {

for( int count = 0; count < 5; count++ )
{
sleep( 1 );
std::cout << "Ping long!" << std::endl;
}

}

void Form::on_btnOpen_clicked() {

QFuture<void> result = QtConcurrent::run ( LongFunction );
//result.waitForFinished();

std::cout << "exit." << std::endl; }

form.ui

<?xml version="1.0" encoding="UTF-8"?> <ui version="4.0">

<class>Form</class>
<widget class="QWidget" name="Form">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>400</width>
<height>300</height>
</rect>
</property>
<property name="windowTitle">
<string>Form</string>
</property>
<layout class="QVBoxLayout" name="verticalLayout">
<item>
<widget class="QPushButton" name="pushButton">
<property name="text">
<string>PushButton</string>
</property>
</widget>
</item>
</layout>
</widget>
<resources/>
<connections/>

</ui>

main.cpp

  1. include <QApplication>
  2. include <QObject>
  3. include <QThread>
  4. include <iostream>
  1. include "form.h"

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

QApplication app(argc, argv);
Form form;
form.show();
return app.exec();

}