怎样使用公共属性

你好：
        我想设定一些公共的定义，以统一各个QML的风格。
于是找到一个文件 UIStyle(内容如下)放在同一目录，但当我在其它QML
引用这些属性时报错。Unable to assign [undefined] to QColor
请问是什么原因，谢谢！
Rectangle {
      color: UIStyle.colorQtGray1
}

import QtQuick 2.7
pragma Singleton
QtObject {
    id: uiStyle
    // Font Sizes
    readonly property int fontSizeXXS: 10
    readonly property int fontSizeXS: 15
    readonly property int fontSizeS: 20
    readonly property int fontSizeM: 25
    readonly property int fontSizeL: 30
    readonly property int fontSizeXL: 35
    readonly property int fontSizeXXL: 40

    // Color Scheme
    // Green
    readonly property color colorQtPrimGreen: "#41cd52"
    readonly property color colorQtAuxGreen1: "#21be2b"
    readonly property color colorQtAuxGreen2: "#17a81a"

    // Gray
    readonly property color colorQtGray1: "#09102b"
    readonly property color colorQtGray2: "#222840"
    readonly property color colorQtGray3: "#3a4055"
    readonly property color colorQtGray4: "#53586b"
    readonly property color colorQtGray5: "#53586b"
    readonly property color colorQtGray6: "#848895"
    readonly property color colorQtGray7: "#9d9faa"
    readonly property color colorQtGray8: "#b5b7bf"
    readonly property color colorQtGray9: "#cecfd5"
    readonly property color colorQtGray10: "#f3f3f4"
}

小韩老师	2018-02-06 20:38
[attachment=18486] 根据助手说明需要三步 [attachment=18487] 单独制作一个模块

neeme	2018-02-07 08:07
小韩老师:[图片] 根据助手说明需要三步 [图片] 单独制作一个模块 ....... (2018-02-06 20:38) 感激不尽！