First of all i need to create a "hello world" app using QML & QT Creator as described here
http://developer.ubuntu.com/get-started/gomobile/

Second, when i was trying to install QML platform and the dependencies i couldn't run the step 2 (of "Install the Ubuntu QML toolkit preview") because i have a distro (backbox) based on ubuntu 12.04 but i solve it by following the instructions of this post:
https://askubuntu.com/questions/235440/how-do-i-install-the-qml-toolkit-on-12-04

Third, when i open QTCreator and trying to execute CurrencyConverter (helloWorld app) the program can't find the following packages:

import Ubuntu.Components 0.1

What can i do in order to run the app?

thanks in advance.

import QtQuick 2.0

import Ubuntu.Components 0.1



Rectangle {

    id: root

    width: units.gu(60)

    height: units.gu(80)

    color: "lightgray"



    property real margins: units.gu(2)

    property real buttonWidth: units.gu(9)



    Label {

       id: title

       ItemStyle.class: "title"

       text: i18n.tr("Currency Converter")

       height: contentHeight + root.margins

       anchors {

           left: parent.left

           right: parent.right

           top: parent.top

       }

    }

}