setting widget as modal, disables button

[munna]

Hi,

I have written the following code in the constructor of class that reimplements QWidget

setAttribute(Qt::WA_DeleteOnClose);
setWindowModality(Qt::WindowModal);
setFixedSize(400,120);
setAutoFillBackground(true);
 
registerButton = new QPushButton(tr("Enter registraion key"),this);

setAttribute(Qt::WA_DeleteOnClose);
setWindowModality(Qt::WindowModal);
setFixedSize(400,120);
setAutoFillBackground(true);

registerButton = new QPushButton(tr("Enter registraion key"),this);

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I am trying to get a modal widget (frameless) on top of my mainwindow. Parent of this widget is the mainwindow of the application. But the registerButton is disabled because of setWindowModal.

Anyideas on why the button is disabled and how can I prevent it from getting disabled ?

Thanks a lot