Multiple Positioner.isLastItem == true properties in one positioner

import QtQuick 2.0

Rectangle {
    width: 100
    height: 400
    color: "#808080"

    Column {
        anchors.fill: parent
        Rectangle {
            width: 100; height: 100
            color: Positioner.isFirstItem ? "red" : (Positioner.isLastItem ? "blue" : "green")
            border.width: 1
            border.color: "black"
        }
        Rectangle {
            width: 100; height: 100
            color: Positioner.isFirstItem ? "red" : (Positioner.isLastItem ? "blue" : "green")
            border.width: 1
            border.color: "black"
        }
        Rectangle {
            width: 100; height: 100
            color: Positioner.isFirstItem ? "red" : (Positioner.isLastItem ? "blue" : "green")
            border.width: 1
            border.color: "black"
        }
        Rectangle {
            width: 100; height: 100
            color: Positioner.isFirstItem ? "red" : (Positioner.isLastItem ? "blue" : "green")
            border.width: 1
            border.color: "black"

            visible: !mouseArea.pressed
        }
    }

    MouseArea {
        id: mouseArea
        anchors.fill: parent
    }
}