QLIstWidget Problem.

[coding_neo]

Hello:
I have a problem using QListWidget. WHat functionality I would like to have is that I create a QLIstWidget. and I want to be able to doubleclick on an item of the QListWidget and have another UI popup. ( for now I am considering QMessageBox as the other UI).
My code is posted below. When I run it, the QListWidget shows up fine, but when I double click on an item nothing happens ( no message box comes up).
What am I doing wrong? (this code is complete as a standalone, so you can copy and paste it as it is in a file in your ide and run it to get understanding.).

# include <QApplication>
# include <QListWidget>
# include <QListWidgetItem>
# include <QHBoxLayout>
# include <QDialog>
# include <QMessageBox>
 
class TestList : public QDialog
{
public:
 
	TestList()
	{
		QListWidget *mList = new QListWidget();
		mList->addItem("Walmart");
		mList->addItem("Ford Motors");
		mList->addItem("Circuit City");
 
		QHBoxLayout *h = new QHBoxLayout();
		h->addWidget(mList);
		this->setLayout(h);
		QListWidgetItem *mItem = new QListWidgetItem();
		QObject::connect(mList,SIGNAL(itemDoubleClicked(QListWidgetItem *mItem)),this,SLOT(test(QListWidgetItem *m)));
 
 
 
	}
 
public slots:
	void test(QListWidgetItem *m)
	{
 
		QMessageBox *t = new QMessageBox(this);
		t->setText(m->text());
		t->setVisible(true); // I tried t->show() here as well but to no effect.
 
	}	
};
 
int main(int argc, char*argv[])
{
      QApplication app (argc,argv);
      TestList *t = new TestList();
       t->show();
        return app.exec();
}

# include <QApplication>
# include <QListWidget>
# include <QListWidgetItem>
# include <QHBoxLayout>
# include <QDialog>
# include <QMessageBox>

class TestList : public QDialog
{
public:
	
	TestList()
	{
		QListWidget *mList = new QListWidget();
		mList->addItem("Walmart");
		mList->addItem("Ford Motors");
		mList->addItem("Circuit City");
		
		QHBoxLayout *h = new QHBoxLayout();
		h->addWidget(mList);
		this->setLayout(h);
		QListWidgetItem *mItem = new QListWidgetItem();
		QObject::connect(mList,SIGNAL(itemDoubleClicked(QListWidgetItem *mItem)),this,SLOT(test(QListWidgetItem *m)));
		
	

	}

public slots:
	void test(QListWidgetItem *m)
	{
		
		QMessageBox *t = new QMessageBox(this);
		t->setText(m->text());
		t->setVisible(true); // I tried t->show() here as well but to no effect.

	}	
};

int main(int argc, char*argv[])
{
      QApplication app (argc,argv);
      TestList *t = new TestList();
       t->show();
        return app.exec();
}

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[mvuori]

What seems to be missing is t->exec(); to execute the message box.

[Jonny174]

main.cpp:

#include <QApplication>
#include <QtGui>
#include "testlist.h"
 
int main(int argc, char*argv[])
{
  QApplication app (argc,argv);
  TestList *t = new TestList();
  t->show();
  return app.exec();
}

#include <QApplication>
#include <QtGui>
#include "testlist.h"

int main(int argc, char*argv[])
{
  QApplication app (argc,argv);
  TestList *t = new TestList();
  t->show();
  return app.exec();
}

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testlist.h:

#ifndef TESTLIST_H
#define TESTLIST_H
 
#include <QListWidget>
#include <QListWidgetItem>
#include <QHBoxLayout>
#include <QDialog>
#include <QMessageBox>
 
class TestList : public QDialog
{
	Q_OBJECT
 
	public:
		TestList( QWidget *parent = 0 ):
			QDialog( parent )
		{
			QListWidget *mList = new QListWidget(this);
			mList->addItem("Walmart");
			mList->addItem("Ford Motors");
			mList->addItem("Circuit City");
 
			QHBoxLayout *h = new QHBoxLayout();
			h->addWidget( mList );
			setLayout(h);
			connect( mList, SIGNAL(itemDoubleClicked(QListWidgetItem*)), this, SLOT(test(QListWidgetItem*)));
		}
 
	public slots:
		void test( QListWidgetItem *m )
		{
			QMessageBox *t = new QMessageBox( this );
			t->setText (m->text() );
			t->exec();
		}
};
 
#endif // TESTLIST_H

#ifndef TESTLIST_H
#define TESTLIST_H

#include <QListWidget>
#include <QListWidgetItem>
#include <QHBoxLayout>
#include <QDialog>
#include <QMessageBox>

class TestList : public QDialog
{
	Q_OBJECT

	public:
		TestList( QWidget *parent = 0 ):
			QDialog( parent )
		{
			QListWidget *mList = new QListWidget(this);
			mList->addItem("Walmart");
			mList->addItem("Ford Motors");
			mList->addItem("Circuit City");

			QHBoxLayout *h = new QHBoxLayout();
			h->addWidget( mList );
			setLayout(h);
			connect( mList, SIGNAL(itemDoubleClicked(QListWidgetItem*)), this, SLOT(test(QListWidgetItem*)));
		}

	public slots:
		void test( QListWidgetItem *m )
		{
			QMessageBox *t = new QMessageBox( this );
			t->setText (m->text() );
			t->exec();
		}
};

#endif // TESTLIST_H

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[Octal]

The code above shows two things :

1/ You forgot the Q_OBJECT macro for signals and slots
2/ You put parameters name instead of just parameters type in SIGNAL and SLOT macros.

By fixing it, your code should work fine.

[coding_neo]

mvuori , Jonny174, Octal:

Thank you all for your replies. I implemented the advisories you had mentioned and now the code is working as expected.
Thank you very Much!