lupdate is not getting tr() strings from QObject objects - qt

Question

I've been trying to make a simple text editor using QT Creator. This text editor has a translatable UI that supports 3 languages: English, Spanish, and Portuguese.
My problem is that every time I run lupdate, string literals in my code that are tagged as translatable (i.e. enclosed in tr() ) are parsed and can be edited and translated using QLinguist. However, strings that are part of QObjects (E.g. ButtonText for QFileDialog are not parsed. Am I missing some procedure in order for lupdate to parse these strings?
void PeterTextEditor::on_actionOpen_triggered()
{
QString fileName = QFileDialog::getOpenFileName(this, tr("Open Document"), QDir::currentPath(),
tr("Text documents (*.txt)"), 0, QFileDialog::DontUseNativeDialog);
if (fileName.isNull())
return;
if ( m_fileName.isNull() && !isWindowModified() )
{
loadFile(fileName);
return;
}
else
{
PeterTextEditor * openFile = new PeterTextEditor( fileName );
openFile->show();
openFile->setAttribute(Qt::WA_DeleteOnClose);
}
}
In above example tr("Open Document") would be parsed, but QFileDialog has QButton and QLabel objects with strings for button text and label text.These are not parsed. I would like these to be parsed so I could add translations using QLinguist.

Answer 1

All compiled translation files (*.qm) should be in the /translations directory and you would load them as shown in QFileDialog localization.
Unfortunately, the Qt libraries don't come with all translations for all languages, and, not all the translations supplied are complete.
For the version that I have (Qt 5.2.1), there is a Spanish translation(qt_es.qm) of the libraries but there are many strings that have not been translated yet, and there is no translation file for Portuguese(qt_pt.qm).
The translation of Qt to other languages is an ongoing project so I suggest you search the web and/or other forums to see if anyone has got updated files you can use.
If you cannot find any, and your Spanish translation is missing a couple of strings you need, you can file the source extraction files(*.ts) in the /Src/qttranslations/translations directory. Unfortunately, you probably will find only one for Spanish.
If you're willing to start a Portuguese translation, you can extract all the necessary strings you want by running lupdate on the /Src/qtbase/qtbase.pro file.