Change language at runtime

[Cobra91151]

Hi! I'm writing my application by code and I have implemented language change in runtime but I don't have ui.retranslateUi(this) function to change text. I have managed to change some text but problem is how to change combobox items text? Thanks in advance for your help.

[joeQ]

@Cobra91151
Hi, friend, welcome devnet.

There is my way. I hope it can help you.

1. First, Tow slots function when changed the language

void MainWindow::StActionLanguageChina()
{
    mpTranslator->load(":/lg/language/lg_ch.qm");// QTranslator load the language file
    qApp->installTranslator(mpTranslator);
}

void MainWindow::StActionLanguageEnglish()
{
    m_pTranslator->load(":/lg/language/lg_en.qm");
    qApp->installTranslator(m_pTranslator);
}

2. rewrite the changeEvent function

void MainWindow::changeEvent(QEvent *event)
{
    //QDialog::changeEvent(event);
    if( QEvent::LanguageChange == event->type() )
    {
        ui->retranslateUi(this);
        ReUiSetText(); // note this function: if you hasn't the ui file, must use this way to translate
    }
}

3. If hasn't ui file, should use the way.

void MainWindow::ReUiSetText()
{
    m_pMenuFile->setTitle(tr("File(&F)"));
    m_pMenuSet->setTitle(tr("Set(&S)"));
    m_pMenuHelp->setTitle(tr("Help(&H)"));
    //...all the language what you want to translate, but not has the ui file. you should rewrite the `set....` at here. to change the language.
}

[Cobra91151]

@joeQ
Thanks but you misunderstood my question. I have already implemented my function Test::appLocalization() in which I change text, the problem is how to change QComboBox items text?

QComboBox did not have property setTitle.

[VRonin]

You basically have to re-execute any line of code that calls tr() so in case of QComboBox:

// QComboBox* comboBox
auto comboModel = comboBox.model();
comboModel->setData(comboModel->index(0,0),tr("Option1"));
comboModel->setData(comboModel->index(1,0),tr("Option2"));
comboModel->setData(comboModel->index(2,0),tr("Option3"));

[kshegunov]

That's one thing the designer shines at - retranslating the whole of the static UI automagically ... :)

[Cobra91151]

@VRonin

I have changed your code to:
comboBox->model()->setData(comboBox->model()->index(0,0), QObject::tr("Text"));

And now it's retranslating QComboBox. I post it here so others can find the solution. Thank you for your reply.