QFileDialog :: getExistingDirectory () run with Error

[VladimirPivovar]

Hi
I have a problem with code: "static QString dir = QFileDialog :: getExistingDirectory ();".
When I call this code section CASE comes with an error message: "Microsoft Visual C + + Runtime Library. This application has requested the Runtime to terminate it in an unusual way". At compile time all is well. But when the - mistake. I do not know why. I tried to call in another project-the same.

I want to get the path to the selected directory.

[goetz]

Leave out the static in front of the QString:

@
QString dir = QFileDialog::getExistingDirectory();
@

[dbzhang800]

Perhaps what he want is something like this:

@
static QString dir;
if (dir.isEmpty())
dir = QFileDialog :: getExistingDirectory ();
@

[VladimirPivovar]

All the same run-time error:

“Microsoft Visual C + + Runtime Library. This application has requested the Runtime to terminate it in an unusual way”

[lgeyer]

Run your application in debug mode to find out where it actually crashes.

[veeraps]

Would copy the binary file (created under Release folder) to Qt bin directory and try executing it from there?

Is it crashing in debug mode as well?

[VladimirPivovar]

in debug and in release mode:

"QWidget: Must construct a QApplication before a QPaintDevice

Invalid parameter passed to C runtime function.
Invalid parameter passed to C runtime function.

"

I run code here:

@

#include <shlobj.h>
#include <QtGui/QApplication>
#include <QObject>
#include <QDebug>
#include <QFileInfo>

int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrev,PSTR szCmdLine,int iCmdShow)
{
....
switch (uMsg)
{
case IDC_CHANGE_DIR:
static QString dir;
if (dir.isEmpty())
dir = QFileDialog :: getExistingDirectory ();
}
break;
...
}
@

[VladimirPivovar]

A similar problem is discussed here, but I can not figure out what to do to bring up a dialog box to select the folder:

http://www.qtforum.org/article/24470/calling-qt-gui-dll-from-mfc-application.html

[dbzhang800]

I couldn't figure out why you using Qt in such a way, can you give us some reasons?

[quote author="VladimirPivovar" date="1338551944"]in debug and in release mode:

"QWidget: Must construct a QApplication before a QPaintDevice

Invalid parameter passed to C runtime function.
Invalid parameter passed to C runtime function.

"

I run code here:
[/quote]

---

BTY, the error message is very clear, you can not construct a QWidget or it's subclass before QApplication exists.