QGraphicsView I'm not geting output

[jthacker]

GraphicTest1::GraphicTest1(QWidget *parent)
    : QGraphicsView(parent)
{
    QGraphicsScene scene;
    scene.addText(QString("HELLO, WORLD!"));
    setScene(&scene);
   show();
}

GraphicTest1::GraphicTest1(QWidget *parent)
    : QGraphicsView(parent)
{
    QGraphicsScene scene;
    scene.addText(QString("HELLO, WORLD!"));
    setScene(&scene);
   show();
}

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i have created the class GraphicTest1 : public QGraphicsView {
...
}
in the constructor i have written above code but i'm not getting output hello world.
but it shows only white blank widget.

help me


note:
Qt 4.6.2
Qt Creator 1.3.1