C++ Qt QlistView signals
************************
My problem is about knowing in what 'item' of a ListView the user has clicked.
I tried with the following program (3 modules plus a Widget from QtDesigner (ui_wex50.h).)

//----------------------------------------------------------------
// wex50.h
//----------------------------------------------------------------
#include <QApplication>

#include <QListWidget>
#include "ui_wex50.h"
#ifndef GRMEM910_H
#define GRMEM910_H
class mywindow : public QWidget, private Ui::Form
{ Q_OBJECT
public: mywindow(QWidget *parent=0); };
//
class mylistWidget : public mywindow, QListWidget
{ public: mylistWidget(QListWidget *);
void myaction(QListWidgetItem *); };
#endif


//----------------------------------------------------------------
// wex50.cpp
//----------------------------------------------------------------
#include <QApplication>

#include <QListWidget>
#include <iostream>

#include "wex50.h"
using namespace std;

mywindow::mywindow(QWidget *)

{ setupUi(this);

QWidget *mywindow = new QWidget;
QListWidget *mylistWidget = new QListWidget(this);
mylistWidget->setGeometry(50,10,40,400);
new QListWidgetItem(tr("A"), mylistWidget);
new QListWidgetItem(tr("B"), mylistWidget);
new QListWidgetItem(tr("C"), mylistWidget);
new QListWidgetItem(tr("D"), mylistWidget);
new QListWidgetItem(tr("F"), mylistWidget);
new QListWidgetItem(tr("G"), mylistWidget);
new QListWidgetItem(tr("H"), mylistWidget);
new QListWidgetItem(tr("I"), mylistWidget);
new QListWidgetItem(tr("J"), mylistWidget);
new QListWidgetItem(tr("K"), mylistWidget);
new QListWidgetItem(tr("L"), mylistWidget);
new QListWidgetItem(tr("M"), mylistWidget);
new QListWidgetItem(tr("N"), mylistWidget);
new QListWidgetItem(tr("O"), mylistWidget);
new QListWidgetItem(tr("P"), mylistWidget);
new QListWidgetItem(tr("Q"), mylistWidget);
new QListWidgetItem(tr("R"), mylistWidget);
new QListWidgetItem(tr("S"), mylistWidget);
new QListWidgetItem(tr("T"), mylistWidget);
new QListWidgetItem(tr("U"), mylistWidget);
new QListWidgetItem(tr("V"), mylistWidget);
new QListWidgetItem(tr("X"), mylistWidget);
new QListWidgetItem(tr("Y"), mylistWidget);
new QListWidgetItem(tr("W"), mylistWidget);
new QListWidgetItem(tr("Z"), mylistWidget);

connect(mylistWidget, SIGNAL(itemClicked(QListWidgetItem *item)), this, SLOT(myaction(void)));

};

//
void mylistWidget::myaction(QListWidgetItem *item)
{ std::cout << item;
mywindow::close(); };


//----------------------------------------------------------------
// ex50.cpp
//----------------------------------------------------------------
#include <QApplication>

#include <QListWidget>
#include "wex50.h"
using namespace std;

int main( int argc, char **argv )
{ QApplication app(argc,argv);
mywindow *Form = new mywindow;
Form->show();
return app.exec(); };
//----------------------------------------------------------------


I've tried to change the signal to:

connect(mylistWidget, SIGNAL(selectionChanged()), this, SLOT(myaction(void)));

both signals were in the Qt documentation, but
when executing the program prints on the console:

Object::connect: No such signal QListWidget::itemClicked()
Object::connect: (receiver name: 'Form')

or

Object::connect: No such signal QListWidget::selectionChanged()
Object::connect: (receiver name: 'Form')

and doesn't recognize the click in the selected letter.

How do I can know what letter was clicked?
Please help me and I'll be gratefull.

Luis Navarro

Hello.

O.K. you have more possibilities :
-take the signal < selectionChanged( QListViewItem * ) > so you get the item the user changed to.
-take the signal < selectionChanged () > and in the member you connected to read then what the current item is < QListViewItem * currentItem () >
-take the signal < void clicked ( QListViewItem * item ) but that means any mouse click, so you have to look what mousebutton is pressed.

It looks like you don't take QT-Designer to create your Widgets. There you get presented what signals you can use and where you can connect to.
The error you get is often because of signals with names, strings as value or the connected member is not in the same class and below. With parent-> you can connect to overlaying Widgets, just parents.

Good luck.

Thanks a lot.
I'm goig to study your proposition.
I'm, newcomer to linux and Qt (I'm learning by myself), even I have a medium experience in C++ Borland Builder for Windows. The Designer module refers itself to others details of my widget that I didn't include to resume the problem.
Thanks and Have a Happy New Year.