How to view QML component with variable settings in Qt designer?

Question

Well I've applied some singleton style in my QML components and with those variable settings I cannot see the proper QML designer view. It's clear that Qt Designer is not able to read those variable values from my style file and render properly.

1. Is there any way to view the component in designer mode when using style variables? In below snippet if I pass actual values designer shows the component as expected.

2. What is best practice in QML to apply common component coloring and sizing factors?

WaveComponent.qml

Rectangle {
    id: waveRect
    width: Style.waveBlockWidth
    height: Style.waveBlockHeight
    color: Style.blockColor
    radius: Style.blockRadius
}