如何在QML中更改TreeView的行选择颜色?

以下代码导致了这种情况:

我不知道蓝色是从哪里来的选择。如何设置TreeView中选定行的背景色?

import QtQuick 2.2
import QtQuick.Controls 1.5
import QtQuick.Controls.Styles 1.4
import QtQml.Models 2.2
import filesystem_browser 1.0

ApplicationWindow
{
    visible: true
    width: 740
    height: 740

    Rectangle
    {
        anchors.centerIn: parent
        color: "#292A38"
        border.color: "#373848"
        height: 600; width: 600

        ItemSelectionModel
        {
            // This model is comming from C++' class DisplayFileSystemModel.
            model: treeViewModel
        }

        TreeView
        {
            id: view
            anchors.fill: parent
            anchors.margins: 2 * 12
            model: treeViewModel
            rootIndex: root
            selection:
                ItemSelectionModel
                {
                    model: treeViewModel

                    onSelectionChanged:
                    {
                        console.log( treeViewModel.data( view.currentIndex ))
                    }
                }

            style:
                TreeViewStyle
                {
                    backgroundColor: "#14161C"
                    highlightedTextColor: "red"
                    alternateBackgroundColor: "#14161C"
                }

            TableViewColumn
            {
                title: "Name"
                role: "display"
                resizable: true
            }

            itemDelegate:
                    Rectangle
                    {
                       color: "transparent"
                       height: 20

                       Rectangle
                       {

                           height: 20; width: 40; color: styleData.depth ? "green":"transparent";
                           anchors.right: parent.right
                           border.width: 1
                       }

                       Text
                       {
                           color: styleData.depth ? "green":"black";
                           anchors.verticalCenter: parent.verticalCenter
                           text: styleData.value
                       }
                   }
            }
    }
}