[SOLVED] cannot catch a signal

[spode]

@
#ifndef MAINWINDOWS_H
#define MAINWINDOWS_H

#include <QObject>
#include <QWidget>
#include <QPushButton>

class MainWindows : public QWidget
{
Q_OBJECT
public:
explicit MainWindows(QWidget *parent = 0);

private:
QPushButton *ingrandimento;
QPushButton *rimpicciolimento;

signals:

private slots:
void updateAll(int newIngrandimento);
};

#endif // MAINWINDOWS_H
@

@

include "mainwindows.h"

#include "guida.h"
#include "programsettings.h"
#include <QVBoxLayout>
#include <QDebug>

MainWindows::MainWindows(QWidget *parent) :
QWidget(parent)
{
this->setWindowFlags(Qt::FramelessWindowHint);

QVBoxLayout *left = new QVBoxLayout(this);
ingrandimento = new QPushButton("Non vedo!!!");
QFont font("Calibri", 26);
font.setBold(true);
ingrandimento->setFont(font);
rimpicciolimento = new QPushButton("Porto gli\nocchiali,\nma ci\nvedo\nancora!!");
QFont font1("Calibri", 24);
font1.setBold(true);
rimpicciolimento->setFont(font1);
left->addWidget(ingrandimento);
left->addWidget(rimpicciolimento);
QObject::connect(ingrandimento, SIGNAL(clicked()), new ProgramSettings(), SLOT(addIngrandimento()));
QObject::connect(rimpicciolimento, SIGNAL(clicked()), new ProgramSettings(), SLOT(reduceIngrandimento()));
QObject::connect(new ProgramSettings, SIGNAL(ingrandimentoChanged(int)), this, SLOT(updateAll(int)));

}

void MainWindows::updateAll(int newIngrandimento)
{
qDebug("updateAll");
ingrandimento->resize(newIngrandimento * 100 + 100, 100 * newIngrandimento + 100);
rimpicciolimento->resize(newIngrandimento * 100 + 100, 100 * newIngrandimento + 100);
qDebug()<<"newIngrandimento: " + newIngrandimento;
}
@

signal comes from:

@
#ifndef PROGRAMSETTINGS_H
#define PROGRAMSETTINGS_H

#include <QObject>
#include <QRect>

class ProgramSettings : public QObject
{
Q_OBJECT

public:
ProgramSettings(QObject *parent = 0);

static int getIngrandimento();
void setIngrandimento(const int nvalue = 1);
static QRect getDesktopDims();
static QSize getDesktopDimsAsQSize();
static int getDesktopWidth();
static int getDesktopHeight();

signals:
void ingrandimentoChanged(int nvalue);

public slots:
void addIngrandimento();
void reduceIngrandimento();
};

#endif // PROGRAMSETTINGS_H
@

@
#include "programsettings.h"

#include <QSettings>
#include <QVariant>
#include <QDesktopWidget>
#include <messaggioantipanico.h>
#include <QDebug>

ProgramSettings::ProgramSettings(QObject *parent) : QObject(parent)
{
}

int ProgramSettings::getIngrandimento()
{
QSettings ss("SeiFreud", "Tecnophobie");
int i = ss.value("ingrandimento", QVariant::fromValue(1)).toInt();
return i;
}

void ProgramSettings::setIngrandimento(const int nvalue)
{
if(nvalue > 0 && nvalue < 4)
{
QSettings s("SeiFreud", "Tecnophobie");
s.setValue("ingrandimento", QVariant::fromValue(nvalue));

    emit ingrandimentoChanged(nvalue);
}
else
{
    MessaggioAntiPanico a("Non è possibile cambiare ulteriormente l' ingrandimento!");
    a.show();
}

}

QRect ProgramSettings::getDesktopDims()
{
QDesktopWidget * d = new QDesktopWidget();
return d->screenGeometry(-1);
}

QSize ProgramSettings::getDesktopDimsAsQSize()
{
QDesktopWidget * d = new QDesktopWidget();
return QSize(d->width(), d->height());
}

int ProgramSettings::getDesktopHeight()
{
return ProgramSettings::getDesktopDims().width();
}

int ProgramSettings::getDesktopWidth()
{
return ProgramSettings::getDesktopDims().height();
}

void ProgramSettings::addIngrandimento()
{
this->setIngrandimento(this->getIngrandimento() + 1);
}

void ProgramSettings::reduceIngrandimento()
{
this->setIngrandimento(this->getIngrandimento() - 1);
@

why does not my PC handle "ingrandimentoChanged" and connect it with the relative slot "updateAll"?

[dmcr]

Hi,

Try to put your ProgramSettings as a variable of your Mainwindows.
As here, it could be already destroyed if no reference is keeped by your application.

dmcr

[spode]

Wonderfull!!! =))

[Neutron Stein]

I think you have to keep a reference to the new ProgramSettings() that you use to make the connections. You should have :
@
#ifndef MAINWINDOWS_H
#define MAINWINDOWS_H

#include <QObject>
#include <QWidget>
#include <QPushButton>
 
class MainWindows : public QWidget
{
    Q_OBJECT
public:
    explicit MainWindows(QWidget *parent = 0);
   
private:
    QPushButton *ingrandimento;
    QPushButton *rimpicciolimento;
    ProgramSettings *programSettings;
 
signals:
   
private slots:
    void updateAll(int newIngrandimento);
};
 
#endif // MAINWINDOWS_H

@
@
include "mainwindows.h"

#include "guida.h"
#include "programsettings.h"
#include <QVBoxLayout>
#include <QDebug>
 
MainWindows::MainWindows(QWidget *parent) :
    QWidget(parent)
{
    this->setWindowFlags(Qt::FramelessWindowHint);
 
    QVBoxLayout *left = new QVBoxLayout(this);
    ingrandimento = new QPushButton("Non vedo!!!");
    QFont font("Calibri", 26);
    font.setBold(true);
    ingrandimento->setFont(font);
    rimpicciolimento = new QPushButton("Porto gli\nocchiali,\nma ci\nvedo\nancora!!");
    QFont font1("Calibri", 24);
    font1.setBold(true);
    rimpicciolimento->setFont(font1);
    left->addWidget(ingrandimento);
    left->addWidget(rimpicciolimento);
    programSettings = new ProgramSettings;
    QObject::connect(ingrandimento, SIGNAL(clicked()),programSettings , SLOT(addIngrandimento()));
    QObject::connect(rimpicciolimento, SIGNAL(clicked()), programSettings, SLOT(reduceIngrandimento()));
    QObject::connect(programSettings, SIGNAL(ingrandimentoChanged(int)), this, SLOT(updateAll(int)));
}
 
void MainWindows::updateAll(int newIngrandimento)
{
    qDebug("updateAll");
    ingrandimento->resize(newIngrandimento * 100 + 100, 100 * newIngrandimento + 100);
    rimpicciolimento->resize(newIngrandimento * 100 + 100, 100 * newIngrandimento + 100);
    qDebug()<<"newIngrandimento: " + newIngrandimento;
}

@