"QML XmlListModel" how to point a local xml file for "source" property？

[useryy2]

Usually, we say

    XmlListModel {
        id: aModel
        source: "content/source.xml"
        query: "/rss/channel/item"

        XmlRole { name: "title"; query: "title/string()" }
        XmlRole { name: "link"; query: "link/string()" }
    }

        ListView {
            id: list
            width: parent.width; height: window.height
            model: aModel
            delegate: Text {
                text: "title is: " + title;
            }
        }

I've got the XmlListModel status 1 (ready), but there is nothing on screen. Why?