How to unload a QDeclarativeView object

Hi,

I loaded a QML file using QDeclarativeView . the sample code is

view = new QDeclarativeView();
view->setSource(QUrl::fromLocalFile("qml/Sample3/main.qml"));
view->show();

On the exit button click i want to unload this qml file.
I tried the "view->hide();" option. but it is not worked.. :(
and also I loaded another QML file in the same QDeclarativeView object like
"view->setSource(QUrl::fromLocalFile("qml/Sample3/test.qml"));" this also not worked... :(
Please give a suitable solution to unload this object.

Thanks in advance....