Q3Frame : no appropraite default constructor available

Class Declaration:-

class TestApp : public Q3Frame
{
public:
TestApp();
TestApp( QWidget *parent, const char* name = 0, Qt::WFlags f=0 );
virtual ~TestApp();
};



CPP File:-

After changing Qframe to Q3Frame, I am getting following error saying :-

Q3Frame : no appropraite default constructor available

TestApp::TestApp()
{
}


TestApp::TestApp( QWidget *parent, const char* name, Qt::WFlags f ) : Q3Frame( parent, name, f )
{
}


TestApp::~TestApp()
{
}

Thanks in advance.

Code:

---

TestApp::TestApp() : Q3Frame( 0 )
{
   // empty
}

---