[SOLVED]QInputDialog causing a seg fault

graham1941

Sirs
I am having a problem with QInputDialog causing a segfault.
Here is my header:-
@#ifndef TRACKRANGES_H
#define TRACKRANGES_H
#include <QInputDialog>
#include <QDialog>
#include <QtGui>

class trackRanges : public QDialog
{
Q_OBJECT

public:
trackRanges();

QInputDialog dlg;
QString ranges;

void getRange(void);

};

#endif // TRACKRANGES_H@

And the implementation:
@#include "trackRanges.h"

trackRanges::trackRanges(){}

void trackRanges::getRange()
{
bool ok = true;
ranges = dlg.getText(NULL,"Track Range","Input range",QLineEdit::Normal, "", &ok);
}@

The common pro file

@#-------------------------------------------------

Project created by QtCreator 2014-11-30T17:50:30

#-------------------------------------------------

QT += core

QT -= gui
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = cdTracks
CONFIG += console
CONFIG -= app_bundle

TEMPLATE = app
LIBS += -lutilities

SOURCES += main.cpp
cdFrameTimes.cpp
trackRanges.cpp

HEADERS +=
cdTracks.h
cdFrameTimes.h
trackRanges.h@

And the calling routine (stub):
@void setUp()
{
QString cmd;
QStringList args;
bool ok;

// QString ranges = QInputDialog::getText(NULL, "title", "label",QLineEdit::Normal, "", &ok);
// dbug<<ranges;

trackRanges *trks = new trackRanges();
trks->getRange();
dbug<<trks->ranges;@

The commented out section in the stub also causes a segfault !!
What am I doing wrong?
Thank you in anticipation
Graham

SGaist

Hi,

@dlg.getText@

This is wrong, getText is a static method so it's not the correct way to do it. Anyway that doesn't explain the crash.

What is dbug ?

What does a run through the debugger tell you ?
What version of Qt/OS are you running ?

graham1941

Thank you SGaist for your reply.
OK I get that about dlg.getText but I also get a segfault at the commented out lines (7 and 8) in the stub. I think there must be something else going on. I will continue to investigate.
dbug is a useful macro of mine set in a utilities header:

@
#include <QDebug>
#ifndef dbug
#define dbug qDebug()<<"["<<FUNCTION<<"; "<<LINE<<"] "
#endif
@

I'm using Qt5 on Linux mint16.
Thank you again
Regards
Graham

SGaist

What does a run through the debugger tell you ?

graham1941

Hi SGaist
The dbugger showed a segfault at line 10 in the stub section.
i tried to write a input dialogue of my own. That failed as well ! The problem is much deeper. I am in the process of starting the whole program from scratch.
Thank you for your advice and help.
Kind regards
Graham.

SGaist

Got any threading involved ?