Common Questions 3 Common Questions Common Questions Find answers to common questions in the GTK+ manual This is an "index" of the reference manual organized by common "How do I..." questions. If you aren't sure which documentation to read for the question you have, this list is a good place to start. Where can I get help with GTK+, submit a bug report, or make a feature request? See the documentation on this topic. How do I port from one GTK+ version to another? See the list of incompatible changes from 1.2 to 2.0. Also, the GNOME 2.0 porting guide on http://developer.gnome.org has some more detailed discussion of porting from 1.2 to 2.0. You may also find useful information in the documentation for specific widgets and functions. If you have a question not covered in the manual, feel free to ask on the mailing lists and please file a bug report against the documentation. How does memory management work in GTK+? Should I free data returned from functions? See the documentation for GObject and GtkObject. For GObject note specifically g_object_ref() and g_object_unref(). GtkObject is a subclass of GObject so the same points apply, except that it has a "floating" state (explained in its documentation). For strings returned from functions, they will be declared "const" (using G_CONST_RETURN) if they should not be freed. Non-const strings should be freed with g_free(). Arrays follow the same rule. (If you find an exception to the rules, please report a bug to http://bugzilla.gnome.org.) How do I use GTK+ with threads? This is covered in the GDK threads documentation. See also the GThread documentation for portable threading primitives. How do I change the color of a widget? See gtk_widget_modify_fg(), gtk_widget_modify_bg(), gtk_widget_modify_base(), and gtk_widget_modify_text(). See GTK+ resource files for more discussion. You can also change widget color by installing a resource file and parsing it with gtk_rc_add_default_file(). The advantage of a resource file is that users can then override the color you've chosen. To change the background color for widgets such as GtkLabel that have no background, place them in a GtkEventBox and set the background of the event box. How do I disable/ghost/desensitize a widget? In GTK+ a disabled widget is termed "insensitive." See gtk_widget_set_sensitive(). How do I get the contents of the entire text widget as a string? See gtk_text_buffer_get_bounds() and gtk_text_buffer_get_text() or gtk_text_iter_get_text(). GtkTextIter start, end; GtkTextBuffer *buffer; char *text; buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (text_view)); gtk_text_buffer_get_bounds (buffer, &start, &end); text = gtk_text_iter_get_text (&start, &end); /* use text */ g_free (text);