import QtQuick 2.5

Rectangle {
    id: root

    ListView {
        id: listView

        anchors.fill: parent
        model: 5
        spacing: 2

        delegate: TestItem {
            width: listView.width
            height: 10

            Rectangle {
                width: 10
                height: 10
                color: "black"
            }
        }
    }

    Rectangle {
        anchors.bottom: parent.bottom

        color: "red"
        width: 20
        height: 20

        MouseArea {
            anchors.fill: parent

            onClicked: {
                listView.model = Math.floor((Math.random() * 10) + 1)
            }
        }
    }
}

import QtQuick 2.5
import QtQuick.Layouts 1.3

Item {
    id: root

    default property alias rowData: row.data

    RowLayout { //if it is changed from RowLayout to Item, all works correctly
        id: row

        anchors.fill: parent
        //Component.onDestruction: data = [] //this hack can solve the problem
    }
}