Encountering segmentation fault while accessing QLineEdit

[franz]

QLineEditPrivate::setText (this=0x0, txt=@0xbff2c200, pos=-1, edited=false) at widgets/qlineedit.cpp:2909

QLineEditPrivate::setText (this=0x0, txt=@0xbff2c200, pos=-1, edited=false) at widgets/qlineedit.cpp:2909

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There's your problem. The QLineEditPrivate doesn't exist (this == 0x0). Most likely cause is that you don't initialize your QLineEdit.

lineEdit = new QLineEdit(this);

lineEdit = new QLineEdit(this);

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[walmac]

Hi, im having the same sort of problem with a QLineEdit. The compiler succesfully compile the project and when you try to change a property of QLineEdit it ends in a segmentation fault... here is my code
ojimetro.cpp

#include <QLabel>
 #include <QTextLine>
#include <QtGui>
//#include <QLineEdit>
#include "ojimetro.h"
 
 
 
Window::Window()
{
        setFixedSize(800, 600);
 
 
        QPushButton *salir = new QPushButton(tr("Salir"), this);
       // salir->setGeometry(1, 1, 75, 30);
        salir->setFont(QFont("Times", 18, QFont::Bold));
        QPushButton *probar = new QPushButton(tr("Probar"), this);
        //probar->setGeometry(76, 1, 75, 30);
        probar->setFont(QFont("Times", 18, QFont::Bold));
        QLabel *viendo=new QLabel(tr("viendo"),this);
        //viendo->setGeometry(150,1,40,40);
        QLineEdit  *lineat=new QLineEdit("casa",this);
 
 
 
 
        connect(salir, SIGNAL(clicked()), qApp, SLOT(quit()));
        connect(probar,SIGNAL(clicked()),this,SLOT(copia()));
        //renderArea->setGeometry(90,100,350,200);
        QGridLayout *mainLayout = new QGridLayout;
        mainLayout->setColumnStretch(0, 1);
        mainLayout->setColumnStretch(3, 1);
        mainLayout->addWidget(renderArea, 0, 0, 1, 4);
        mainLayout->setRowMinimumHeight(1, 6);
        mainLayout->addWidget(viendo, 2, 1, Qt::AlignRight);
        mainLayout->addWidget(lineat, 2, 2);
        mainLayout->addWidget(salir, 3, 1, Qt::AlignRight);
        mainLayout->addWidget(probar, 3, 2);
 
 
 
        setLayout(mainLayout);
        //renderArea->adjustSize();
        //dato=lineat->text();
 
 
        setWindowTitle(tr("Ojimetro v0.1"));
 
 
}
 
void Window::copia()
{
    int a,b,c;
    QString texto1;
    int poin;
 
 
 
    a=1;
 
    //texto1=lineat->text();
    //this->lineat->setText("oo");
    //qDebug() << this->lineat->text();
    b=2;
    c=0;
 
   lineat->setText("hola!!!");
    c=a+b;
    a=2;
 
 
 
}

#include <QLabel>
 #include <QTextLine>
#include <QtGui>
//#include <QLineEdit>
#include "ojimetro.h"



Window::Window()
{
        setFixedSize(800, 600);
       

        QPushButton *salir = new QPushButton(tr("Salir"), this);
       // salir->setGeometry(1, 1, 75, 30);
        salir->setFont(QFont("Times", 18, QFont::Bold));
        QPushButton *probar = new QPushButton(tr("Probar"), this);
        //probar->setGeometry(76, 1, 75, 30);
        probar->setFont(QFont("Times", 18, QFont::Bold));
        QLabel *viendo=new QLabel(tr("viendo"),this);
        //viendo->setGeometry(150,1,40,40);
        QLineEdit  *lineat=new QLineEdit("casa",this);

       


        connect(salir, SIGNAL(clicked()), qApp, SLOT(quit()));
        connect(probar,SIGNAL(clicked()),this,SLOT(copia()));
        //renderArea->setGeometry(90,100,350,200);
        QGridLayout *mainLayout = new QGridLayout;
        mainLayout->setColumnStretch(0, 1);
        mainLayout->setColumnStretch(3, 1);
        mainLayout->addWidget(renderArea, 0, 0, 1, 4);
        mainLayout->setRowMinimumHeight(1, 6);
        mainLayout->addWidget(viendo, 2, 1, Qt::AlignRight);
        mainLayout->addWidget(lineat, 2, 2);
        mainLayout->addWidget(salir, 3, 1, Qt::AlignRight);
        mainLayout->addWidget(probar, 3, 2);



        setLayout(mainLayout);
        //renderArea->adjustSize();
        //dato=lineat->text();


        setWindowTitle(tr("Ojimetro v0.1"));


}

void Window::copia()
{
    int a,b,c;
    QString texto1;
    int poin;



    a=1;

    //texto1=lineat->text();
    //this->lineat->setText("oo");
    //qDebug() << this->lineat->text();
    b=2;
    c=0;

   lineat->setText("hola!!!");
    c=a+b;
    a=2;



}

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when im debugging, the debugger stops at lineat->setText("hola!!!") and shows the segmentation fault
ojimetro.h

#ifndef OJIMETRO_H
#define OJIMETRO_H
 #include <QTextLine>
#include <QWidget>
#include <QObject>
QT_BEGIN_NAMESPACE
class QCheckBox;
class QLineEdit;
class QComboBox;
class QLabel;
class QSpinBox;
class QTextLine;
QT_END_NAMESPACE
 
 
 
class Window : public QWidget
{
    Q_OBJECT
        public:
 
       Window();
 
    public slots:
          void copia();
 
 
public:
 QLineEdit *lineat;
#endif // OJIMETRO_H
};

#ifndef OJIMETRO_H
#define OJIMETRO_H
 #include <QTextLine>
#include <QWidget>
#include <QObject>
QT_BEGIN_NAMESPACE
class QCheckBox;
class QLineEdit;
class QComboBox;
class QLabel;
class QSpinBox;
class QTextLine;
QT_END_NAMESPACE



class Window : public QWidget
{
    Q_OBJECT
        public:

       Window();

    public slots:
          void copia();
   

public:
 QLineEdit *lineat;
#endif // OJIMETRO_H
};

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gbd reports this...

Program received signal SIGSEGV, Segmentation fault.
0x009b54e5 in QLineEdit::setText (this=0x3e4be8, text=@0x22cee8)
at widgets\qlineedit.cpp:383
383 widgets\qlineedit.cpp: No such file or directory.
in widgets\qlineedit.cpp


i forgot to say what im trying to do.. The idea is just to get the text of the QLineEdit, in this code, im setting the text but it does the same error. thanks in advance!