QFileDialog::getSaveFileName and default selectedFilter

Question

I have getSaveFileName with some filters and I want one of them to be selected when user opens the "Save" dialog. Qt documentation says the following:

The default filter can be chosen by setting selectedFilter to the desired value.

I try the following variant:

QString selFilter="All files (*.*)";
QFileDialog::getSaveFileName(this,"Save file",QDir::currentPath(),
    "Text files (*.txt);;All files (*.*)",&selFilter);

But when the dialog appears, the "Text files" filter (in general case, the first filter from the list) is selected. I also tried all of the following:

selFilter="All files";
selFilter="All files (*.*)\n";
selFilter="All files (*.*);;";
selFilter="All files (*.*)\0";

and different mixtures of this variants. The format of the filter list in my code is done according to the documentation (example line from Qt docs):

"Images (*.png *.xpm *.jpg);;Text files (*.txt);;XML files (*.xml)"

Note that output to selFilter variable works properly: after user press OK, selFilter variable contains the filter selected by the user.

Platform: Linux(OpenSUSE 12.1), Qt 4.7.4, gcc 4.6.2.

So how to set up the default filter?!

Answer 1

You may try this sample application and verify, if it makes any difference. When you use direct dialog construction as in this case you have more control over the object.

#include <QApplication>
#include <QFileDialog>

int main(int argc, char **argv)
{
    QApplication app(argc,argv);

    QString filters("Music files (*.mp3);;Text files (*.txt);;All files (*.*)");
    QString defaultFilter("Text files (*.txt)");

    /* Static method approach */
    QFileDialog::getSaveFileName(0, "Save file", QDir::currentPath(),
        filters, &defaultFilter);

    /* Direct object construction approach */
    QFileDialog fileDialog(0, "Save file", QDir::currentPath(), filters);
    fileDialog.selectNameFilter(defaultFilter);
    fileDialog.exec();

    return 0;
}

Normally such kind of behavior is a sign of memory corruption. However, I've checked that with valgrind (I have Qt 4.8.1) and there are only some false positives from FontConfig.