[lazarus] Problem found

T Jan Schmidt c9517606 at studentmailbox.newcastle.edu.au
Wed Jun 30 00:43:24 EDT 1999

In C++, I got around the problem of having no self (this) pointer by
making a global function as the callback, and having a self pointer as
part of the widget data (as in my previous email). I was looking for a
quick and dirty fix, so I used public methods on the class(object) and
simply typecast the widget data "self" pointer to the type I wanted, then
called the public method on that object. 

A better solution (in C++) would have been something like:

class X {
  friend void callback(...);
   void Handler();

void callback(...)
  X *obj = ( X* (gtk_object_get_data(GTK_OBJECT(Widget),"self")));

This relies on the "friend" C++ construct. I don't know if there is an
equivalent for Delphi - a modifier that says a global function is allowed
to call private member functions on the object. If there isn't, I don't
see a solution that doesn't involve making the object methods public.



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