Harbour C Extensions Xhgtk¶

Prikazaću najinteresantnije dijelove, da bih se upoznali sa načinom kako je napravljen binding prema gtk/gdk/cairo bibilotekama:

general.c¶

...

HB_FUNC( GTK_MAIN )
{
    gtk_main();
}

HB_FUNC( GTK_INIT )
{
    if (! initialized)
    {
        initialized = TRUE;
        gtk_init(NULL,NULL);
    }
}

HB_FUNC( GTK_MAIN_QUIT )
{
    GList *list;
    gchar *role = NULL;

    list = gtk_window_list_toplevels();
    list = g_list_first(list);

    while (list)
    {
        if (GTK_IS_WINDOW(list->data))
        {
            role = g_strdup(gtk_window_get_role( GTK_WINDOW(list->data) ));

            if (role && strcmp(role, "window") == 0)
                   gtk_widget_destroy( GTK_WIDGET(list->data) );

            g_free(role);
        }
        list = g_list_next(list);
    }

    g_list_free(list);
    gtk_main_quit();
}

...

general.c xhgtk_locale_to_utf8 , xhgtk_locale_from_utf8¶

gtk, glib-doc: file:///usr/share/gtk-doc/html/glib/glib-Character-Set-Conversion.html#g-locale-to-utf8

g_locale_to_utf8 ():

• Converts a string which is in the encoding used for strings by the C runtime (usually the same as that used by the operating system) in the current locale into a UTF-8 string.

g_filename_to_utf8 ():

• Converts a string which is in the encoding used by GLib for filenames into a UTF-8 string. Note that on Windows GLib uses UTF-8 for filenames; on other platforms, this function indirectly depends on the current locale.

Locale (glib)¶

A number of interfaces in GLib depend on the current locale in which an application is running. Therefore, most GLib-using applications should call setlocale (LC_ALL, "") to set up the current locale.

On Windows, in a C program there are several locale concepts that not necessarily are synchronized. On one hand, there is the system default ANSI code-page, which determines what encoding is used for file names handled by the C library's functions and the Win32 API. (We are talking about the "narrow" functions here that take character pointers, not the "wide" ones.)

On the other hand, there is the C library's current locale. The character set (code-page) used by that is not necessarily the same as the system default ANSI code-page. Strings in this character set are returned by functions like strftime.

gchar * xhgtk_locale_to_utf8( const gchar *szLocale )
{
    gchar *szText;
    GError *error = NULL;

    if (! g_utf8_validate(szLocale, -1, NULL))
        if (strlen(sLocale) > 0)
            szText = g_convert(szLocale, -1, "UTF-8", sLocale, NULL, NULL, &error );
        else
            szText = g_locale_to_utf8(szLocale, -1, NULL, NULL, NULL);  <<<<<<<<<<<<<<<<<< g_locale_to_utf8 glib c funkcija
    else
        szText = g_strdup( szLocale );

    if (error != NULL)
    {
        g_print("UTF-8 convertion failed !");
        g_error_free(error);
    }

    return szText;
}

gchar * xhgtk_locale_from_utf8( const gchar *szLocale )
{
gchar *szText;
GError *error = NULL;

    if (strlen(sLocale) > 0)
        szText = g_convert(szLocale, -1, sLocale, "UTF-8", NULL, NULL, &error );
    else
        szText = g_locale_from_utf8( szLocale, -1, NULL, NULL, NULL);   <<<<<<<<<<<<<<<<<< g_locale_from_utf8 glib c funkcija  

    if (error != NULL)
    {
        g_print("UTF-8 convertion failed !");
        g_error_free(error);
    }
    return szText;
}

primjetimo da se radi o dvije c utility funkcije koje interno koristi xhgtk, a nikada direktno harbour applikacija.

gmain.c¶

#include "xhgtk.h" 

HB_FUNC( G_MAIN_LOOP_NEW )
{
    hb_retptr( (GMainLoop *) g_main_loop_new( (GMainContext *) hb_parptr(1), hb_parl(2)) );
}

HB_FUNC( G_MAIN_LOOP_RUN )
{
    g_main_loop_run( (GMainLoop *) hb_parptr(1) );
}

HB_FUNC( G_MAIN_LOOP_QUIT )
{
    g_main_loop_quit( (GMainLoop *) hb_parptr(1) );
}

HB_FUNC( G_MAIN_LOOP_UNREF )
{
    g_main_loop_unref( (GMainLoop *) hb_parptr(1) );
}

HB_FUNC( G_MAIN_LOOP_IS_RUNNING )
{
    hb_retl( g_main_loop_is_running( (GMainLoop *) hb_parptr(1) ) );
}

TWindow.prg: METHOD Activate() CLASS TWindow¶

METHOD Activate() CLASS TWindow
....

    if ::Main
        hMainWindow := ::handle
        gtk_signal_connect(::handle, "destroy", {|| lMain := .F., gtk_main_quit()})
        gtk_main()
    elseif ::Loop
        gtk_signal_connect(::handle, "destroy", {|| g_main_loop_quit(::hMainLoop)})
        ::hMainLoop := g_main_loop_new(NIL, FALSE)
        g_main_loop_run(::hMainLoop)
        g_main_loop_unref(::hMainLoop)
        ::hMainLoop = NIL
    endif

RETURN nil

primjer: xhgtk_font_dialog¶

#include "xhgtk.h" 

HB_FUNC( XHGTK_FONT_DIALOG )
{
    GtkWidget *dialog;
    char *fontname;
    gchar *szText = xhgtk_locale_to_utf8( hb_parcx(1) );

    dialog = gtk_font_selection_dialog_new(szText);
    gtk_window_set_role(GTK_WINDOW(dialog), "window" );
    gtk_dialog_run(GTK_DIALOG (dialog));

    fontname = gtk_font_selection_dialog_get_font_name (GTK_FONT_SELECTION_DIALOG(dialog));

    hb_retc(fontname);    <<<<<<<<<<<<<<<<<<<<<<<<<<<<<< hb_retc  ( char * => harbour string )
    g_free(fontname);
    g_free(szText);

    gtk_widget_destroy(dialog);
}

gtk/gtklabel.c¶

/* GtkWidget* gtk_label_new (const char *str); */
HB_FUNC( GTK_LABEL_NEW )
{
    gchar *szText = xhgtk_locale_to_utf8(hb_parcx(1));    <<<<<<<<<<  uzmi prvi parametar iz harbour-a: hb_parcx(1)

    hb_retptr( ( GtkWidget * ) gtk_label_new(szText) );   <<<<<<<<<<  vrati pointer na novokreirani objekat: hb_retptr( c_object );

    g_free(szText);
}

/* void gtk_label_set_text (GtkLabel *label, const char *str); */
HB_FUNC( GTK_LABEL_SET_TEXT )
{
    gchar *szText = xhgtk_locale_to_utf8 (hb_parcx(2));          <<<<<<< drugi parametar je utf string (gchar *)

    gtk_label_set_text( ( GtkLabel * ) hb_parptr(1), szText );   <<<<<<< prvi parametar je pointer na gtk_label objekat
    g_free(szText);
}