Strange segmentation fault

[Lykurg]

Hi,

I have following class:

#ifndef NORMALSEARCHWIDGET_H
#define NORMALSEARCHWIDGET_H
 
#include <QWidget>
#include <QBoxLayout>
class listBrowserWidget;
 
class normalSearchWidget : public QWidget
{
  Q_OBJECT
public:
  normalSearchWidget(QWidget *parent = 0);
  ~normalSearchWidget();
public slots:
  void setLbTbDirection ( QBoxLayout::Direction direction );
private:
  listBrowserWidget *lbw1;
  listBrowserWidget *lbw2;
  QBoxLayout *layout;
};
#endif

#ifndef NORMALSEARCHWIDGET_H
#define NORMALSEARCHWIDGET_H

#include <QWidget>
#include <QBoxLayout>
class listBrowserWidget;

class normalSearchWidget : public QWidget
{
  Q_OBJECT
public:
  normalSearchWidget(QWidget *parent = 0);
  ~normalSearchWidget();
public slots:
  void setLbTbDirection ( QBoxLayout::Direction direction );
private:
  listBrowserWidget *lbw1;
  listBrowserWidget *lbw2;
  QBoxLayout *layout;
};
#endif

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#include <QBoxLayout>
 
#include "normalsearchwidget.h"
#include "listbrowserwidget.h"
 
normalSearchWidget::normalSearchWidget(QWidget *parent)
    : QWidget(parent)
{
  layout = new QBoxLayout( QBoxLayout::TopToBottom );
  layout->setMargin( 0 );
  layout->setSpacing( 2 );
 
  listBrowserWidget *lbw1 = new listBrowserWidget();
  listBrowserWidget *lbw2 = new listBrowserWidget();
 
  layout->addWidget(lbw1);
  layout->addWidget(lbw2);
 
  this->setLayout( layout );
 
  // Next line works ( same line as in setLbTbDirection(QBoxLayout::Direction direction) )
  lbw1->setDirection( QBoxLayout::TopToBottom );
 
  // with this line I get and segmentation fault!
  setLbTbDirection( QBoxLayout::TopToBottom );
}
 
normalSearchWidget::~normalSearchWidget()
{}
 
void normalSearchWidget::setLbTbDirection ( QBoxLayout::Direction direction )
{
  lbw1->setDirection( QBoxLayout::TopToBottom );
}

#include <QBoxLayout>

#include "normalsearchwidget.h"
#include "listbrowserwidget.h"

normalSearchWidget::normalSearchWidget(QWidget *parent)
    : QWidget(parent)
{
  layout = new QBoxLayout( QBoxLayout::TopToBottom );
  layout->setMargin( 0 );
  layout->setSpacing( 2 );

  listBrowserWidget *lbw1 = new listBrowserWidget();
  listBrowserWidget *lbw2 = new listBrowserWidget();

  layout->addWidget(lbw1);
  layout->addWidget(lbw2);

  this->setLayout( layout );

  // Next line works ( same line as in setLbTbDirection(QBoxLayout::Direction direction) )
  lbw1->setDirection( QBoxLayout::TopToBottom );

  // with this line I get and segmentation fault!
  setLbTbDirection( QBoxLayout::TopToBottom );
}

normalSearchWidget::~normalSearchWidget()
{}

void normalSearchWidget::setLbTbDirection ( QBoxLayout::Direction direction )
{
  lbw1->setDirection( QBoxLayout::TopToBottom );
}

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As discribed in the commentar, I don't anderstand, why a statement in the constructor works and in a lokal function it causes an segFault. The function itself, without the line, works also perfekt.
I yet have deleted all generatet files, and have recompiled my program, but the error is still there.

Thanks for help,
Lykurg

[jacek]

listBrowserWidget *lbw1 = new listBrowserWidget();
listBrowserWidget *lbw2 = new listBrowserWidget();

These are local variables. normalSearchWidget::lbw1 and normalSearchWidget::lbw2 remain uninitialized.

[Lykurg]

These are local variables. normalSearchWidget::lbw1 and normalSearchWidget::lbw2 remain uninitialized.

Arrgg, you are right, of course! I hate failures like that...

Thanks
Lykurg

[Popp]

Thanks you too!
I had the same stupid failure...
... because of copy-pasting form Tutorials.