main.qml

    import QtQuick 2.6
    import QtQuick.Controls 1.5

    ApplicationWindow {
        id: applicationWindow
        visible: true
        width: 640
        height: 480

        Label {
            id: helloLabel
            height: 50
            anchors {
                top: parent.top
                left: parent.left
                right: parent.horizontalCenter
                margins: 10
            }
        }

        ComboBox {
            id: comboBox
            anchors {
                top: parent.top
                left: parent.horizontalCenter
                right: parent.right
                margins: 10
            }

            model: ["ru_RU", "en_US"]

            // If you change the text, initialize the translation unit via C++ Layer
            onCurrentTextChanged: {
                qmlTranslator.setTranslation(comboBox.currentText)
            }
        }

        Label {
            id: labelText
            wrapMode: Text.Wrap
            anchors {
                top: helloLabel.bottom
                left: parent.left
                right: parent.right
                margins: 10
            }
        }

        // Connect to an interpreter object
        Connections {
            target: qmlTranslator   // was registered in main.cpp
            onLanguageChanged: {    // upon receipt of the signal to change the language
                retranslateUi()     // initialize interface translation
            }
        }

        // interface translation function
        function retranslateUi() {
            applicationWindow.title = qsTr("Hello World")
            helloLabel.text = qsTr("Hello World")
            labelText.text = qsTr("The QTranslator class provides internationalization" +
                                  "support for text output.An object of this class contains " +
                                  "a set of translations from a source language to a target language. " +
                                  "QTranslator provides functions to look up translations in a translation file. " +
                                  "Translation files are created using Qt Linguist.")
        }

        // Start translating the application window when the application was created
        Component.onCompleted: {
            retranslateUi();
        }
    }