How to resize window with pushbutton

[kaydknight]

Hi, I'm a total newbie with Qt. Have been looking the QT assistant help for a while to figure out how to resize the window by pressing just a pushbutton

Below is my code snippet:

QApplication app(argc,argv);
QPushButton quit("Quit");
...
...
QObject::connect(&quit, SIGNAL(clicked()), &app, SLOT(resize(500,500));

QApplication app(argc,argv);
QPushButton quit("Quit");
...
...
QObject::connect(&quit, SIGNAL(clicked()), &app, SLOT(resize(500,500));

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When I press the pushbutton, the app is still not resized. I'm just trying to get a hang on qt, and that's why I just really want to know how to do this.

I read the assistant which said that if i call for resize, then a resize event will automatically occur, but somehow the app is not resizing at all. Hope anyone can help on this. Thanks in advance!