Blackberry Cascades SystemDialog theme

I'm using this manual to create ok/cancel modal dialog box in my Blackberry 10 application.

I defined dialog in QML and called .show() method. The dialog works well, but it always uses bright(white) theme. Even if current theme set to dark and all other controls are dark - the dialog is always white.

Is there any way to make the dialog work as all others controls in application.

Here my QML fragment with dialog:

 SystemDialog {
    id: interruptDialog
    title: qsTr("title")
    body: qsTr("Do you really want to do this?")
    onFinished: {
       someAction();
    }
 }