Automatically saving a file with QFileDialog - c++

Question

I have to automate a test using QTest, Qt, C++:
I write text in a tab (part of tabwidget) and then try to close it, afterwards a QFileDialog appears ( because I made changes to the plaintext in the tab), I try to "catch" the QFileDialog like this:
QWidgetList topWidgets = QApplication::topLevelWidgets();
foreach (QWidget *w, topWidgets) {
if (QFileDialog *fd = qobject_cast<QFileDialog *>(w)) {
fd->setFileMode(QFileDialog::ExistingFiles);
fd->selectFile("/tmp/test.txt");
}
}
After getting the QFileDialog object I want my changes from the tab to be saved in the file "test.txt" which I created before in the tmp directory. When I execute this nothing happens, the QFileDialog pops up, but test.txt is not selected and not saved, how can I achieve this?

Answer 1

The selectFile method does not work if the filedialog is visible and if the focus is set to the line edit widget. From the qfiledialog.cpp (QT 5.2):
if (!isVisible() || !d->lineEdit()->hasFocus())
d->lineEdit()->setText(file);
For our automated tests, we just hide the filedialog for a moment, call selectFile() and show it again

Answer 2

Try this:
QWidgetList topWidgets = QApplication::topLevelWidgets();
foreach (QWidget *w, topWidgets) {
if (QFileDialog *fd = qobject_cast<QFileDialog *>(w)) {
fd->hide();
fd->selectFile("/tmp/test.txt");
fd->show();
fd->exec();
}
}