如何从QML中的listview访问currentItem的角色？

ListView {
    id: listView
    model: myModel
    delegate: myDelegate
}

Component {
    id: myDelegate
    Rectangle {
        id: delegateItem
        property string roleValue: model.roleValue
        // ...
    }
}

function getCurrentItemRoleValue() {
    var currentItem = listView.currentItem;
    if (currentItem) {
        var roleValue = currentItem.roleValue;
        console.log("Current item's role value: " + roleValue);
    } else {
        console.log("No current item selected");
    }
}