Dropshadow Opacity Problem

[jondoe]

Hello,
I have 1 rectangle and this rectangle transparent black. When I dont using drop shadow my transparent black rectangle working good but when i using drop shadow my transparent black rectangle changing to flat black and opacity not working. What problem here ? how can i fix it ? Thank you

Codes here

Rectangle {
id:borderbottom
smooth: true
x: 1
y: topmenuback.height
width: topmenuback.width
height: 10
opacity: 0.1
color: "#CC000000"
}

            DropShadow {
                anchors.fill: borderbottom
                horizontalOffset: 10
                verticalOffset: 10
                radius: 8.0
                samples: 17
                color: "#CC000000"
                source: borderbottom
            }

[jondoe]

Help please :(

[LeLev]

@jondoe hi

 Rectangle {
    id:borderbottom
    smooth: true
    x: 1

    width: 50
    height: 50
    opacity: 0.1
    color: "#CC000000"
    layer.enabled: true
    layer.effect: DropShadow {
        anchors.fill: borderbottom
        horizontalOffset: 10
        verticalOffset: 10
        radius: 8.0
        samples: 17
        color: "#CC000000"
        source: borderbottom
    }
    }