Segmentation Fault accessing QListWidget

[ljshap]

I am a total QT noob !!!!!

I am receiving a SIGSEGV error when I try adding an item to a QListWidget object. The objected was created in the class constructor and is part of the constructor layout. It crashes when I try adding an item in a seperate function. I have no problems adding to the object in the constructor or adding items to an object created in the function but can not add to the constructor object from the separate function:

Any suggestions would be appreciated especially since it may help explain a lot of other problems.

Thanks
------------------------------

The following is an extract of the code:

//direct.h
 
#include <QPushButton>
//
class direct : public QDialog
{
Q_OBJECT
 
 
public:
 
 
	QListWidget * listWidget ; //= new QListWidget;
	QPushButton * button1 ; 
 
public slots:
void  getSelectedNames();
 
public:
	direct();
 
};
#endif

//direct.h

#include <QPushButton>
//
class direct : public QDialog
{
Q_OBJECT


public:
	 
	
	QListWidget * listWidget ; //= new QListWidget;
	QPushButton * button1 ; 

public slots:
void  getSelectedNames();

public:
	direct();
	
};
#endif

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//=======================================================
// S o u r c e   F i l e
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++
#include "direct.h"
 
direct::direct(  )   : QDialog()
{
 
	QVBoxLayout * mainLayout = new QVBoxLayout(this);
 
	QPushButton * button1 = new QPushButton("List Files");
	QPushButton * quit = new QPushButton("Quit");
 
//	mainLayout->addWidget(listWidget);	
	mainLayout->addWidget(button1);
 
 
	// Conections	
	connect (button1 ,   SIGNAL (clicked ()  ),   this,    SLOT  (getSelectedNames ()   )    );
	connect (quit, SIGNAL (clicked() ), this, SLOT (accept() ) );
}
 
 
 
 
void direct::getSelectedNames()
{
 
 
for (int i1 =0; i1<45;i1++)
	{
		//listWidget->setCurrentRow(i1);
  		newList->addItem("xxx");	                 // SEGMENTATION FAULT - but not if in the constructor
 
	}

//=======================================================
// S o u r c e   F i l e
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++
#include "direct.h"

direct::direct(  )   : QDialog()
{

	QVBoxLayout * mainLayout = new QVBoxLayout(this);
	
	QPushButton * button1 = new QPushButton("List Files");
	QPushButton * quit = new QPushButton("Quit");

//	mainLayout->addWidget(listWidget);	
	mainLayout->addWidget(button1);

	
	// Conections	
	connect (button1 ,   SIGNAL (clicked ()  ),   this,    SLOT  (getSelectedNames ()   )    );
	connect (quit, SIGNAL (clicked() ), this, SLOT (accept() ) );
}


    

void direct::getSelectedNames()
{
	

for (int i1 =0; i1<45;i1++)
	{
		//listWidget->setCurrentRow(i1);
  		newList->addItem("xxx");	                 // SEGMENTATION FAULT - but not if in the constructor
	
	}

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[munna]

Add the following line in your constructor

listWidget = new QListWidget(this);

listWidget = new QListWidget(this);

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Also, I see that the following line is not correct

newList->addItem("xxx"); // SEGMENTATION FAULT - but not if in the constructor

newList->addItem("xxx"); // SEGMENTATION FAULT - but not if in the constructor

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There is no variable called newList

[ljshap]

[QUOTE=munna;88097]Add the following line in your constructor

listWidget = new QListWidget(this);

listWidget = new QListWidget(this);

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Including "this" did the trick. // Thanks

There is no variable called newList

That was just a mistake in trimming the code, I tried a lot of different things.

Thanks again for your help!