File Browse Window

HI
I need to create a file browse window , the window should be opening up on the click of the button.
The image of the file browser app is attached.

I have written the code on the SLOT function for the button SIGNAL( clicked)

Code:

---

QDirModel model;
    QTreeView tree;
    tree.setModel(&model);
 
    tree.setRootIndex(model.index(QDir::homePath()));
    tree.setColumnHidden( 1, true );
    tree.setColumnHidden( 2, true );
    tree.setColumnHidden( 3, true );
 
    tree.setWindowTitle(QObject::tr("Dir View:")+QDir::homePath());
    tree.resize(640, 480);
    tree.show();

---

But I get the error at QDirModel model;

Whar error?

while running the code theres no error, but while debugging
QDirModel model
The code goes into QGrayRaster.c