retranslate not updating dynamically in Qt6.2, but ok in Qt5.15

[Leon Zhang]

Hello,

Translator and retranslate works fine in Qt5.15, but not updating display dynamically when upgrade to Qt6.2; Need to reload qml manually to display translated language.

qml file as follow:

import QtQuick
import QtQuick.Controls

ApplicationWindow {
    width: 640
    height: 480
    visible: true
    title: qsTr("Hello World")

    property bool eng: true

    Column {
        spacing: 10

        Text {
            text: Tr.ssetWeighCycle
        }

        Button {
            width: 100
            height: 44
            text: eng ? "English" : "Japanese"
            onClicked: {
                eng = !eng
                if (eng) {
                    translate.selectLanguage(0)
                } else {
                    translate.selectLanguage(1)
                }
                //reload loader2 then translate works
                loader2.source = ""
                loader2.source = "panel.qml"
            }
        }
    }

    Row {
        spacing: 10
        anchors.centerIn: parent
        Loader {
            id:loader
            width: 200
            height: 200
            source: "panel.qml"
        }

        Loader {
            id:loader2
            width: 200
            height: 200
            source: "panel.qml"
        }
    }
}

[lemons]

I always do the translation switch from C++ like this:

Translator::Translator(QQmlEngine *engine)
{
    _translator = new QTranslator(this);
    _engine = engine;
}

void Translator::selectLanguage(QString language)
{
    QString path = ":/i18n";
    if (!_translator->load(language, "AppName",  "_", path, ".qm"))
    {
        qDebug() << "Failed to load translation file, falling back to English";
    }
    qApp->installTranslator(_translator);
    
    // change default e.g. for dates | decimals
    QLocale::setDefault(language);

    // no QML reload required, handled automatically by engine
    _engine->retranslate();

    // if you want to do anything else onLanguageChanged
    emit languageChanged();
}