Launching new form by a button click in qt gui application?

Hi im a newbie to QT im trying upon some simple applications.. i'd like to know how to launch a new form by clicking a button from main window.. please explain me with a simple example.. when i create a new project say myqt it'll generate 1) a from "mainwindow.ui" 2) a header "mainwindow.h" 3) two source files "main.cpp" and "mainwindow.cpp".. now i need to add a from say "myform.ui" how do i launch or make the form visible when i press a button from "mainwindow" gimme some tutorials..

http://doc.qt.nokia.com/4.7/tutorials-addressbook.html

http://doc.qt.nokia.com/4.7/tutorials.html
http://doc.qt.nokia.com/4.7/all-examples.html

You can make a button then add slot that will show it smt like
connect(button, SIGNAL(clicked), this, slotShow());

in slot show
widget x = new widget();
x->show();

Thanks dude!!