Ubuntu – How to dynamically add tab to tabs

I am trying to add a new tab to the tabs component with the code below.

When running there is no error reported but no additional tabs are show.
I have tried using both tabs and tabs.__tabsModel as the parent but no additional tabs are show.

import QtQuick 2.0
import QtQuick.LocalStorage 2.0
import Ubuntu.Components 0.1

MainView {
    // objectName for functional testing purposes (autopilot-qt5)
    id: mainView
    objectName: "mainView"
    applicationName: "news-feed"

    width: units.gu(100)
    height: units.gu(75)

    Tabs {
        id: tabs
        anchors.fill: parent

        Component.onCompleted: {
            mainView.initializeDB();
            mainView.saveFeed("BBC News","http://feeds.bbci.co.uk/news/rss.xml");
            mainView.saveFeed("Jono Bacon","http://www.jonobacon.org/?feed=rss2");
            mainView.saveFeed("The Register", "http://www.theregister.co.uk/headlines.atom");
            fillTabs();
        }

        tools: ToolbarActions {
            Action {
                objectName: "action"

                iconSource: Qt.resolvedUrl("avatar.png")
                text: i18n.tr("Tap me!")

                onTriggered: {
                    label.text = i18n.tr("Toolbar tapped")
                }
            }
        }

        // First tab begins here
        Tab {
            id: tabFrontPage
            objectName: "tabFrontPage"

            title: i18n.tr("Front Page")

            // Tab content begins here
            page: Page {
                Column {
                    anchors.centerIn: parent
                    Label {
                        id: labelFrontPage
                        text: i18n.tr("This will be the front page \n An aggregation of the top stories from each feed")
                    }
                }
            }
        }
    }

    function fillTabs() {
        var db = getDatabase();
        db.transaction(function(tx) {
            var rs = tx.executeSql('SELECT * FROM feeds;');
            if (rs.rows.length > 0) {
                for(var i = 0; i < rs.rows.length; i++) {
                    var feedTab = Qt.createQmlObject('import QtQuick 2.0;import Ubuntu.Components 0.1;Tab {anchors.fill: parent;objectName: "Tab";title: i18n.tr("Tab");page: Page {anchors.margins: units.gu(2);Column {anchors.centerIn: parent;Label {id: label;objectName: "label";text: i18n.tr("Tab");}}}}',tabs,"feedTab");
                }
            } else {
                res = "Unknown";
            }
        })
    }
    //Storage API
    function getDatabase() {
        return LocalStorage.openDatabaseSync("news-feed","1.0","StorageDatabase",10000)
    }

    //Initialise DB tables if not already existing
    function initializeDB() {
        var db = getDatabase();
        db.transaction(function(tx) {
            //Create settings table if not existing
            tx.executeSql('CREATE TABLE IF NOT EXISTS settings(setting TEXT UNIQUE, value TEXT)');
            tx.executeSql('CREATE TABLE IF NOT EXISTS feeds(feedName TEXT UNIQUE, feedURL TEXT UNIQUE)')
        });
    }

    //Write setting to DB
    function setSetting(setting,value){
        //setting: string - setting name (key)
        //value: string - value
        var db = getDatabase();
        var res = "";
        db.transaction(function(tx) {
            var rs = tx.executeSql('INSERT OR REPLACE INTO settings VALUES (?,?);',[setting,value]);
            //console.log(rs.rowsAffected)
            if(rs.rowsAffected > 0) {
                res = "OK";
            } else {
                res = "Error";
            }
        })
        return res;
    }

    //Read setting from DB
    function getSetting(setting) {
        var db = getDatabase();
        var res="";
        db.transaction(function(tx) {
            var rs = tx.executeSql('SELECT value FROM settings WHERE setting=?;', [setting]);
            if (rs.rows.length > 0) {
                res = rs.rows.item(0).value;
            } else {
                res = "Unknown";
            }
        })
        return res;
    }

    function saveFeed(feedName, feedURL) {
        var db = getDatabase();
        var res = "";
        db.transaction(function(tx){
            var rs = tx.executeSql('INSERT OR REPLACE INTO feeds VALUES (?,?)',[feedName,feedURL]);
            //console.log(rs.rowsAffected)
            if (rs.rowsAffected > 0) {
                res = "OK";
            } else {
                res = "Error";
            }
        })
        return res;
    }

    //Return a single feed
    function getFeed(feedName) {
        var db = getDatabase();
        var res = "";
        db.transaction(function(tx) {
            var rs = tx.executeSql('SELECT feedURL FROM feeds WHERE feedName=?;', [feedName]);
            if (rs.rows.length > 0) {
                res = rs.rows.item(0).feedURL;
            } else {
                res = "Unknown";
            }

        })
        return res;
    }

    //Return all feeds and urls
    function getFeeds() {
        var db = getDatabase();
        var res = "";
        db.transaction(function(tx) {
            var rs = tx.executeSql('SELECT * FROM feeds;');
            if (rs.rows.length > 0) {
                return rs;
            } else {
                res = "Unknown";
            }
        })
        return res;
    }
}