Problem with WA_TranslucentBackground Attribute.

[Sung Sean]

Hello.

I make some app using Qt.

I write custom widget and set transparent. But, I can't hide child widget of my custom widget.

Simply pseudo code in below, someone help me, please.

class widgetA : public QWidget { ...... }
class widgetB : public QWidget { ...... }

main()
{
    widgetA mainW();
    widgetB childW(&mainW);

    // for transparent.
    // without below line, testFunc() is okay.
    // with below line, childW->hide() is not working.
    mainW.setAttribute(Qt::WA_TranslucentBackground);
    .......
}

wA::testFunc( bool show )
{
    if( show ) childW->show();
    else childW->hide();
}

If I set WA_TranslucentBackground, childW->hide() not working.
When I call childW->hide(), childW still show in my app.

If I not set WA_TranslucentBackground, childW->show/hide() work fine.

I using Qt Embedded 4.8 on ARM device, but same result in ubuntu on my desktop.

Am I made some mistake or something...?

Thank you.