/GTK 4.0


GtkBuilderScope — Bindings for GtkBuilder

Object Hierarchy

    ╰── GtkBuilderScope
    ╰── GtkBuilderCScope


GtkBuilderScope requires GObject.

Implemented Interfaces

GtkBuilderCScope implements GtkBuilderScope.

Known Implementations

GtkBuilderScope is implemented by GtkBuilderCScope.


#include <gtk/gtk.h>


GtkBuilderScope is an interface to provide support to GtkBuilder, primarily for looking up programming-language-specific values for strings that are given in a GtkBuilder UI file.

The primary intended audience is bindings that want to provide deeper integration of GtkBuilder into the language.

A GtkBuilderScope instance may be used with multiple GtkBuilder objects, even at once.

By default, GTK will use its own implementation of GtkBuilderScope for the C language which can be created via gtk_builder_cscope_new().

GtkBuilderCScope instances use symbols explicitly added to builder with prior calls to gtk_builder_cscope_add_callback_symbol(). If developers want to do that, they are encouraged to create their own scopes for that purpose.

In the case that symbols are not explicitly added; GTK will uses GModule’s introspective features (by opening the module NULL) to look at the application’s symbol table. From here it tries to match the signal function names given in the interface description with symbols in the application.

Note that unless gtk_builder_cscope_add_callback_symbol() is called for all signal callbacks which are referenced by the loaded XML, this functionality will require that GModule be supported on the platform.


gtk_builder_cscope_new ()

GtkBuilderScope *
gtk_builder_cscope_new (void);

Creates a new GtkBuilderCScope object to use with future GtkBuilder instances.

Calling this function is only necessary if you want to add custom callbacks via gtk_builder_cscope_add_callback_symbol().


a new GtkBuilderCScope.

[transfer full][type GtkBuilderCScope]

gtk_builder_cscope_add_callback_symbol ()

                               (GtkBuilderCScope *self,
                                const char *callback_name,
                                GCallback callback_symbol);

Adds the callback_symbol to the scope of builder under the given callback_name .

Using this function overrides the behavior of gtk_builder_create_closure() for any callback symbols that are added. Using this method allows for better encapsulation as it does not require that callback symbols be declared in the global namespace.



a GtkBuilderCScope


The name of the callback, as expected in the XML


The callback pointer.

[scope async]

gtk_builder_cscope_add_callback_symbols ()

                               (GtkBuilderCScope *self,
                                const char *first_callback_name,
                                GCallback first_callback_symbol,

A convenience function to add many callbacks instead of calling gtk_builder_cscope_add_callback_symbol() for each symbol.




a GtkBuilderCScope


The name of the callback, as expected in the XML


The callback pointer.

[scope async]


A list of callback name and callback symbol pairs terminated with NULL

gtk_builder_cscope_lookup_callback_symbol ()

                               (GtkBuilderCScope *self,
                                const char *callback_name);

Fetches a symbol previously added to self with gtk_builder_cscope_add_callback_symbol().




a GtkBuilderCScope


The name of the callback


The callback symbol in builder for callback_name , or NULL.

[nullable][transfer none]

Types and Values


typedef struct _GtkBuilderScope GtkBuilderScope;

enum GtkBuilderClosureFlags

The list of flags that can be passed to gtk_builder_create_closure(). New values may be added in the future for new features, so external implementations of GtkBuilderScopeInterface should test the flags for unknown values and raise a GTK_BUILDER_ERROR_INVALID_ATTRIBUTE error when they encounter one.



The closure should be created swapped. See g_cclosure_new_swap() for details.

struct GtkBuilderScopeInterface

struct GtkBuilderScopeInterface {
  GType                 (* get_type_from_name)                  (GtkBuilderScope        *self,
                                                                 GtkBuilder             *builder,
                                                                 const char             *type_name);
  GType                 (* get_type_from_function)              (GtkBuilderScope        *self,
                                                                 GtkBuilder             *builder,
                                                                 const char             *function_name);

  GClosure *            (* create_closure)                      (GtkBuilderScope        *self,
                                                                 GtkBuilder             *builder,
                                                                 const char             *function_name,
                                                                 GtkBuilderClosureFlags  flags,
                                                                 GObject                *object,
                                                                 GError                **error);

The virtual function table to implement for GtkBuilderScope implementations. Default implementations for each function do exist, but they usually just fail, so it is suggested that implementations implement all of them.


get_type_from_name ()

Try to lookup a GType via the its name. See gtk_builder_get_type_from_name() for more details. The C implementation will use g_type_from_name() and if that fails try to guess the correct function name for registering the type and then use dlsym() to load it. The default implementation just tries g_type_from_name() and otherwise fails.

get_type_from_function ()

Try to lookup a GType via the given function name, specified explicitly in a GtkBuilder file, like via the "type-func" attribute in the "<object>" tag. This function is very rarely used. The C implementation will use dlsym() and call the resulting function as a GTypeFunc. The default implementation will fail and just return G_TYPE_INVALID.

create_closure ()

Create a closure with the given arguments. See gtk_builder_create_closure() for more details on those. The C implementation will try to use dlsym() to locate the function name and then g_cclosure_new() to create a closure for the symbol. The default implementation just fails and returns NULL.


typedef struct _GtkBuilderCScope GtkBuilderCScope;

See Also

GtkBuilder, GClosure

© 2005–2020 The GNOME Project
Licensed under the GNU Lesser General Public License version 2.1 or later.