Blackberry 基于标签值的标签颜色

我有一个容器，上面有这样的标签。。。 但是如果标签值为负值，我需要添加红色，否则为绿色。如何在Qml中的BB 10级联中执行此操作

Container {
    leftPadding: 15.0
    rightPadding: 15.0
    layout: StackLayout {
        orientation: LayoutOrientation.LeftToRight
    }
    topPadding: 20.0

    Label {
        id: symbol
        text: ListItemData.Symbol_En

        // Text Style and size etc
        textStyle.base: SystemDefaults.TextStyles.SubtitleText
        textStyle.fontSizeValue: 30.0
        layoutProperties: StackLayoutProperties {
            spaceQuota: 4
        }
        verticalAlignment: VerticalAlignment.Center
        horizontalAlignment: HorizontalAlignment.Center

    }
    Label {
        id: change
        text: ListItemData.PerChange
        textStyle.base: SystemDefaults.TextStyles.SubtitleText
        textStyle.fontSizeValue: 30.0
        layoutProperties: StackLayoutProperties {
            spaceQuota: 2
        }
        verticalAlignment: VerticalAlignment.Center
        horizontalAlignment: HorizontalAlignment.Center

    }
    Label {
        id: ltp
        text: ListItemData.LTP
        textStyle.base: SystemDefaults.TextStyles.SubtitleText
        textStyle.fontSizeValue: 30.0
        layoutProperties: StackLayoutProperties {
            spaceQuota: 1
        }
        verticalAlignment: VerticalAlignment.Center
        horizontalAlignment: HorizontalAlignment.Center

    }
    Label {
        id: highValue
        text: ListItemData.High
        textStyle.base: SystemDefaults.TextStyles.SubtitleText
        textStyle.fontSizeValue: 30.0
        layoutProperties: StackLayoutProperties {
            spaceQuota: 1
        }
        verticalAlignment: VerticalAlignment.Center
        horizontalAlignment: HorizontalAlignment.Center

    }
    Label {
        id: lowValue
        text: ListItemData.Low
        textStyle.base: SystemDefaults.TextStyles.SubtitleText
        textStyle.fontSizeValue: 30.0
        layoutProperties: StackLayoutProperties {
            spaceQuota: 1
        }
        verticalAlignment: VerticalAlignment.Center
        horizontalAlignment: HorizontalAlignment.Center

    }

---

像这样的东西怎么样（只是有问题的标签）：

标签{
id:高值
文本：ListItemData.High
textStyle.color:ListItemData.High.indexOf（“-”）小于0？颜色。绿色：颜色。红色
textStyle.base:SystemDefaults.TextStyles.subtitlettext
textStyle.fontSizeValue:30.0
layoutProperties:StackLayoutProperties{
名额：1
}
垂直对齐：垂直对齐。中心
水平对齐：水平对齐。居中
}

您想给哪个标签上色？哪个值？id为highValue的标签。如果是负片，我需要红色，绿色，但这里是ListItemData。是否可以像ListItemData.High.contains（'-'）那样进行比较？你用parseInt怎么样。我在中添加了它，而不是.contains，您可以使用.indexOf（“-”）0。如果里面有“-”，则会得到0，否则会得到-1ListItemData.High.indexOf（“-”），请尝试打印数据，看看会得到什么。我测试了这个，它是有效的<代码>.indexOf（“-”）是否小于0？颜色.绿色：颜色.红色

Label {
        id: highValue
        text: ListItemData.High
        textStyle.color: ListItemData.High.indexOf("-") < 0 ? Color.Green : Color.Red 
        textStyle.base: SystemDefaults.TextStyles.SubtitleText
        textStyle.fontSizeValue: 30.0
        layoutProperties: StackLayoutProperties {
            spaceQuota: 1
        }
        verticalAlignment: VerticalAlignment.Center
        horizontalAlignment: HorizontalAlignment.Center
    }