Comment 1 for bug 1211483

I'm exposing the icons in the SwitchStyle in the linked branch. So when that lands, you can use the following to change the look of the Switch for a single instance (for more instances, it is recommended to create a custom theme that derives from Ambience instead of this):

import QtQuick 2.2
import Ubuntu.Components 1.1
import Ubuntu.Components.Themes.Ambiance 1.1 as Ambience

MainView {
    id: root
    useDeprecatedToolbar: false

    width: units.gu(30)
    height: units.gu(40)

    Switch {
        id: testSwitch
        anchors.centerIn: parent
        width: units.gu(10)
        height: units.gu(5)
        checked: true
        style: Ambience.SwitchStyle {
            checkedIconSource: "image://theme/stock_video"
            uncheckedIconSource: "image://theme/stock_image"
            checkedThumbColor: "red"
        }
    }
}