How to open QMainWindow object from QDialog object as an active window

[sanjeet]

I want to open QMainWindow Object in QDialog Object as an active window or top level window.

My code is like this :

connect ((open button on QDialog object)), SIGNAL (clicked()),this , SLOT (openMyForm()));

void MyDialog:penMyForm()
{
myForm = new QMainWindow;
myForm->show();
}

I have even used setActivateWindow() and raise() function call in openMyForm slot but still it's not working.