How to get a 1 pixel black border on a frameless dialog?

[SPlatten]

I have a couple of instances of a Dialog which I don't want a titlebar or widgets, so I call:

setWindowFlags(Qt::FramelessWindowHint);

In the class constructor, however I would like a single pixel, maybe 2 pixel black border around the dialog just to make it clear and standout when it overlays another dialog of the same background colour.

I've tried setting the style sheet using:

setStyleSheet("QDialog {border:1px solid black}");

It doesn't do anything.

[Hanson]

You can try to override the paintEvent, maybe works.

void YourWidget::paintEvent(QPaintEvent *)
{
QStyleOption opt;
opt.init(this);
QPainter p(this);
style()->drawPrimitive(QStyle::PE_Widget, &opt, &p, this);
}

[Thank You]

@SPlatten
Set the stylesheet in the dialog

using the editor

Below is the code

If it didn't solve can you show more ? like how are you putting stylesheet?