QFrame questions

[zephod]

I have a few questions about frames.
Here is a test program I have been experimenting with

class BuildGui : public QMainApplication
{
public:
    BuildGui(QWidget* parent = 0);
private:
    QWidget* makeWidget(QString text);
 
    QVBoxLayout* layout;
};
 
BuildGui::BuildGui(QWidget* parent = 0) : QMainApplication(parent)
{
    QWidget* w1 = makeWidget("Ex 1");
    QWidget* w2 = makeWidget("Ex 2");
 
    layout = new QVBoxLayout;
    layout->addWidget(w1);
    layout->addWidget(w2);
 
    QWidget* cw = new QWidget;
    cw->setLayout(layout);
 
    QScrollArea* sa = new QScrollArea;
    sa->setWidget(cw);
 
    setCentralWidget(sa);
}    
 
QWidget* BuildGui::makeWidget(QString text)
{
    QLineEdit* le = new QLineEdit(text);
    return le;
}

class BuildGui : public QMainApplication
{
public:
    BuildGui(QWidget* parent = 0);
private:
    QWidget* makeWidget(QString text);

    QVBoxLayout* layout;
};

BuildGui::BuildGui(QWidget* parent = 0) : QMainApplication(parent)
{
    QWidget* w1 = makeWidget("Ex 1");
    QWidget* w2 = makeWidget("Ex 2");

    layout = new QVBoxLayout;
    layout->addWidget(w1);
    layout->addWidget(w2);

    QWidget* cw = new QWidget;
    cw->setLayout(layout);

    QScrollArea* sa = new QScrollArea;
    sa->setWidget(cw);

    setCentralWidget(sa);
}    

QWidget* BuildGui::makeWidget(QString text)
{
    QLineEdit* le = new QLineEdit(text);
    return le;
}

To copy to clipboard, switch view to plain text mode 

which works as expected - I see the 2 text boxes one above the other with "Ex 1" and "Ex 2" for the text.

Now I add this method:

QWidget* BuildGui::addFrame(QWidget w)
{
    QFrame* f = new QFrame;
    f->setFrameStyle(QFrame::Box);
    w->setParent(f);
    return f;
}

QWidget* BuildGui::addFrame(QWidget w)
{
    QFrame* f = new QFrame;
    f->setFrameStyle(QFrame::Box);
    w->setParent(f);
    return f;
}

To copy to clipboard, switch view to plain text mode 

and modify the constructor:

QWidget* f1 = addFrame(sc1);
    ...
    // layout->setWidget(w1);
    layout->setWidget(f1);

QWidget* f1 = addFrame(sc1);
    ...
    // layout->setWidget(w1);
    layout->setWidget(f1);

To copy to clipboard, switch view to plain text mode 

now the "Ex 1" box does not show up. If I add

f1->setMinimumSize(50,50);

f1->setMinimumSize(50,50);

To copy to clipboard, switch view to plain text mode 

then it is visible.
So my question is
Can i make the frame automatically adjust to the size of the widget it is framing?

Thanks,
Steve

PS I know some widgets have a setFrame() method but I want this to work for framinh any widget.