Re: Object Orientation in GTK

[Havoc Pennington <rhpennin midway uchicago edu>]

On Sat, 7 Nov 1998, Matthew Ettus wrote:
> 
> On the other hand, it seems to encourage the use of global variables. 
> In many instances, I see no way of avoiding global variables.
> 

It's trivial; just use structs and methods that act on them.

/* define MyApp object */
typedef struct _MyApp MyApp;

struct _MyApp {
 GtkWidget* main_window;
 /* other data too */
};

void my_app_quit(MyApp* app);
void my_app_foo(MyApp* app, MyFooData* foo);
etc.

You can do everything with this that you could do with:
class MyApp {
 void quit();
};

Though of course it will be less safe and involve more typing.

Plain structs are fairly limited as objects; if you want a "real" object
you can make a GtkObject descendant. This gives you signals and
inheritance and type checking.

Havoc