GtkBuilder: GTK+ 3 Reference Manual

## GtkBuilder GtkBuilder — Build an interface from an XML UI definition |

## Functions

void | (*GtkBuilderConnectFunc) ()
GtkBuilder * | gtk_builder_new ()
GtkBuilder * | gtk_builder_new_from_file ()
GtkBuilder * | gtk_builder_new_from_resource ()
GtkBuilder * | gtk_builder_new_from_string ()
void | gtk_builder_add_callback_symbol ()
void | gtk_builder_add_callback_symbols ()
GCallback | gtk_builder_lookup_callback_symbol ()
guint | gtk_builder_add_from_file ()
guint | gtk_builder_add_from_resource ()
guint | gtk_builder_add_from_string ()
guint | gtk_builder_add_objects_from_file ()
guint | gtk_builder_add_objects_from_string ()
guint | gtk_builder_add_objects_from_resource ()
GObject * | gtk_builder_get_object ()
GSList * | gtk_builder_get_objects ()
void | gtk_builder_expose_object ()
void | gtk_builder_connect_signals ()
void | gtk_builder_connect_signals_full ()
void | gtk_builder_set_translation_domain ()
const gchar * | gtk_builder_get_translation_domain ()
void | gtk_builder_set_application ()
GtkApplication * | gtk_builder_get_application ()
GType | gtk_builder_get_type_from_name ()
gboolean | gtk_builder_value_from_string ()
gboolean | gtk_builder_value_from_string_type ()
#define | GTK_BUILDER_WARN_INVALID_CHILD_TYPE()
#define | GTK_BUILDER_ERROR

## Properties

gchar * | translation-domain | Read / Write

## Types and Values

| GtkBuilder
enum | GtkBuilderError

## Object Hierarchy

        GObject
        ╰── GtkBuilder

## Includes

    #include <gtk/gtk.h>

## Description

A GtkBuilder is an auxiliary object that reads textual descriptions of a user interface and instantiates the described objects. To create a GtkBuilder from a user interface description, call `gtk_builder_new_from_file()`, `gtk_builder_new_from_resource()` or `gtk_builder_new_from_string()`.

In the (unusual) case that you want to add user interface descriptions from multiple sources to the same GtkBuilder you can call `gtk_builder_new()` to get an empty builder and populate it by (multiple) calls to `gtk_builder_add_from_file()`, `gtk_builder_add_from_resource()` or `gtk_builder_add_from_string()`.

A GtkBuilder holds a reference to all objects that it has constructed and drops these references when it is finalized. This finalization can cause the destruction of non-widget objects or widgets which are not contained in a toplevel window. For toplevel windows constructed by a builder, it is the responsibility of the user to call `gtk_widget_destroy()` to get rid of them and all the widgets they contain.

The functions `gtk_builder_get_object()` and `gtk_builder_get_objects()` can be used to access the widgets in the interface by the names assigned to them inside the UI description. Toplevel windows returned by these functions will stay around until the user explicitly destroys them with `gtk_widget_destroy()`. Other widgets will either be part of a larger hierarchy constructed by the builder (in which case you should not have to worry about their lifecycle), or without a parent, in which case they have to be added to some container to make use of them. Non-widget objects need to be reffed with `g_object_ref()` to keep them beyond the lifespan of the builder.

The function `gtk_builder_connect_signals()` and variants thereof can be used to connect handlers to the named signals in the description.

### GtkBuilder UI Definitions

GtkBuilder parses textual descriptions of user interfaces which are specified in an XML format which can be roughly described by the RELAX NG schema below. We refer to these descriptions as “GtkBuilder UI definitions” or just “UI definitions” if the context is clear. Do not confuse GtkBuilder UI Definitions with GtkUIManager UI Definitions, which are more limited in scope. It is common to use `.ui` as the filename extension for files containing GtkBuilder UI definitions.

RELAX NG Compact Syntax

The toplevel element is <interface>. It optionally takes a “domain” attribute, which will make the builder look for translated strings using `dgettext()` in the domain specified. This can also be done by calling `gtk_builder_set_translation_domain()` on the builder. Objects are described by <object> elements, which can contain <property> elements to set properties, <signal> elements which connect signals to handlers, and <child> elements, which describe child objects (most often widgets inside a container, but also e.g. actions in an action group, or columns in a tree model). A <child> element contains an <object> element which describes the child object. The target toolkit version(s) are described by <requires> elements, the “lib” attribute specifies the widget library in question (currently the only supported value is “gtk+”) and the “version” attribute specifies the target version in the form “<major>.<minor>”. The builder will error out if the version requirements are not met.

Typically, the specific kind of object represented by an <object> element is specified by the “class” attribute. If the type has not been loaded yet, GTK+ tries to find the `get_type()` function from the class name by applying heuristics. This works in most cases, but if necessary, it is possible to specify the name of the `get_type()` function explictly with the "type-func" attribute. As a special case, GtkBuilder allows to use an object that has been constructed by a GtkUIManager in another part of the UI definition by specifying the id of the GtkUIManager in the “constructor” attribute and the name of the object in the “id” attribute.

Objects may be given a name with the “id” attribute, which allows the application to retrieve them from the builder with `gtk_builder_get_object()`. An id is also necessary to use the object as property value in other parts of the UI definition. GTK+ reserves ids starting and ending with ___ (3 underscores) for its own purposes.

Setting properties of objects is pretty straightforward with the <property> element: the “name” attribute specifies the name of the property, and the content of the element specifies the value. If the “translatable” attribute is set to a true value, GTK+ uses `gettext()` (or `dgettext()` if the builder has a translation domain set) to find a translation for the value. This happens before the value is parsed, so it can be used for properties of any type, but it is probably most useful for string properties. It is also possible to specify a context to disambiguate short strings, and comments which may help the translators.

GtkBuilder can parse textual representations for the most common property types: characters, strings, integers, floating-point numbers, booleans (strings like “TRUE”, “t”, “yes”, “y”, “1” are interpreted as `TRUE`, strings like “FALSE”, “f”, “no”, “n”, “0” are interpreted as `FALSE`), enumerations (can be specified by their name, nick or integer value), flags (can be specified by their name, nick, integer value, optionally combined with “|”, e.g. “GTK_VISIBLE|GTK_REALIZED”) and colors (in a format understood by `gdk_rgba_parse()`). Pixbufs can be specified as a filename of an image file to load. Objects can be referred to by their name and by default refer to objects declared in the local xml fragment and objects exposed via `gtk_builder_expose_object()`.

In general, GtkBuilder allows forward references to objects — declared in the local xml; an object doesn’t have to be constructed before it can be referred to. The exception to this rule is that an object has to be constructed before it can be used as the value of a construct-only property.

It is also possible to bind a property value to another object's property value using the attributes "bind-source" to specify the source object of the binding, "bind-property" to specify the source property and optionally "bind-flags" to specify the binding flags Internally builder implement this using GBinding objects. For more information see `g_object_bind_property()`

Signal handlers are set up with the <signal> element. The “name” attribute specifies the name of the signal, and the “handler” attribute specifies the function to connect to the signal. By default, GTK+ tries to find the handler using `g_module_symbol()`, but this can be changed by passing a custom GtkBuilderConnectFunc to `gtk_builder_connect_signals_full()`. The remaining attributes, “after”, “swapped” and “object”, have the same meaning as the corresponding parameters of the `g_signal_connect_object()` or `g_signal_connect_data()` functions. A “last_modification_time” attribute is also allowed, but it does not have a meaning to the builder.

Sometimes it is necessary to refer to widgets which have implicitly been constructed by GTK+ as part of a composite widget, to set properties on them or to add further children (e.g. the `vbox` of a GtkDialog). This can be achieved by setting the “internal-child” propery of the <child> element to a true value. Note that GtkBuilder still requires an <object> element for the internal child, even if it has already been constructed.

A number of widgets have different places where a child can be added (e.g. tabs vs. page content in notebooks). This can be reflected in a UI definition by specifying the “type” attribute on a <child> The possible values for the “type” attribute are described in the sections describing the widget-specific portions of UI definitions.

### A GtkBuilder UI Definition

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    <interface>
      <object class="GtkDialog" id="dialog1">
        <child internal-child="vbox">
          <object class="GtkBox" id="vbox1">
            <property name="border-width">10</property>
            <child internal-child="action_area">
              <object class="GtkButtonBox" id="hbuttonbox1">
                <property name="border-width">20</property>
                <child>
                  <object class="GtkButton" id="ok_button">
                    <property name="label">gtk-ok</property>
                    <property name="use-stock">TRUE</property>
                    <signal name="clicked" handler="ok_button_clicked"/>
                  </object>
                </child>
              </object>
            </child>
          </object>
        </child>
      </object>
    </interface>

Beyond this general structure, several object classes define their own XML DTD fragments for filling in the ANY placeholders in the DTD above. Note that a custom element in a <child> element gets parsed by the custom tag handler of the parent object, while a custom element in an <object> element gets parsed by the custom tag handler of the object.

These XML fragments are explained in the documentation of the respective objects.

Additionally, since 3.10 a special <template> tag has been added to the format allowing one to define a widget class’s components.

## Functions

### GtkBuilderConnectFunc ()

    void
    (*GtkBuilderConnectFunc) (GtkBuilder *builder,
                              GObject *object,
                              const gchar *signal_name,
                              const gchar *handler_name,
                              GObject *connect_object,
                              GConnectFlags flags,
                              gpointer user_data);

This is the signature of a function used to connect signals. It is used by the `gtk_builder_connect_signals()` and `gtk_builder_connect_signals_full()` methods. It is mainly intended for interpreted language bindings, but could be useful where the programmer wants more control over the signal connection process. Note that this function can only be called once, subsequent calls will do nothing.

#### Parameters

builder | a GtkBuilder |
object | object to connect a signal to |
signal_name | name of the signal |
handler_name | name of the handler |
connect_object | a GObject, if non-`NULL`, use `g_signal_connect_object()`. | [nullable]
flags | GConnectFlags to use |
user_data | user data |

Since 2.12

### gtk_builder_new ()

    GtkBuilder *
    gtk_builder_new (void);

Creates a new empty builder object.

This function is only useful if you intend to make multiple calls to `gtk_builder_add_from_file()`, `gtk_builder_add_from_resource()` or `gtk_builder_add_from_string()` in order to merge multiple UI descriptions into a single builder.

Most users will probably want to use `gtk_builder_new_from_file()`, `gtk_builder_new_from_resource()` or `gtk_builder_new_from_string()`.

#### Returns

a new (empty) GtkBuilder object

Since 2.12

### gtk_builder_new_from_file ()

    GtkBuilder *
    gtk_builder_new_from_file (const gchar *filename);

Builds the GtkBuilder UI definition in the file `filename` .

If there is an error opening the file or parsing the description then the program will be aborted. You should only ever attempt to parse user interface descriptions that are shipped as part of your program.

#### Parameters

filename | filename of user interface description file |

#### Returns

a GtkBuilder containing the described interface

Since 3.10

### gtk_builder_new_from_resource ()

    GtkBuilder *
    gtk_builder_new_from_resource (const gchar *resource_path);

Builds the GtkBuilder UI definition at `resource_path` .

If there is an error locating the resource or parsing the description, then the program will be aborted.

#### Parameters

resource_path | a GResource resource path |

#### Returns

a GtkBuilder containing the described interface

Since 3.10

### gtk_builder_new_from_string ()

    GtkBuilder *
    gtk_builder_new_from_string (const gchar *string,
                                 gssize length);

Builds the user interface described by `string` (in the GtkBuilder UI definition format).

If `string` is `NULL`-terminated, then `length` should be -1. If `length` is not -1, then it is the length of `string` .

If there is an error parsing `string` then the program will be aborted. You should not attempt to parse user interface description from untrusted sources.

#### Parameters

string | a user interface (XML) description |
length | the length of `string` , or -1 |

#### Returns

a GtkBuilder containing the interface described by `string`

Since 3.10

### gtk_builder_add_callback_symbol ()

    void
    gtk_builder_add_callback_symbol (GtkBuilder *builder,
                                     const gchar *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_connect_signals()` 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.

#### Parameters

builder | a GtkBuilder |
callback_name | The name of the callback, as expected in the XML |
callback_symbol | The callback pointer. | [scope async]

Since 3.10

### gtk_builder_add_callback_symbols ()

    void
    gtk_builder_add_callback_symbols (GtkBuilder *builder,
                                      const gchar *first_callback_name,
                                      GCallback first_callback_symbol,
                                      ...);

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

#### Parameters

builder | a GtkBuilder |
first_callback_name | The name of the callback, as expected in the XML |
first_callback_symbol | The callback pointer. | [scope async]
... | A list of callback name and callback symbol pairs terminated with `NULL` |

Since 3.10

### gtk_builder_lookup_callback_symbol ()

    GCallback
    gtk_builder_lookup_callback_symbol (GtkBuilder *builder,
                                        const gchar *callback_name);

Fetches a symbol previously added to `builder` with `gtk_builder_add_callback_symbols()`

This function is intended for possible use in language bindings or for any case that one might be cusomizing signal connections using `gtk_builder_connect_signals_full()`

#### Parameters

builder | a GtkBuilder |
callback_name | The name of the callback |

#### Returns

The callback symbol in `builder` for `callback_name` , or `NULL`

Since 3.10

### gtk_builder_add_from_file ()

    guint
    gtk_builder_add_from_file (GtkBuilder *builder,
                               const gchar *filename,
                               GError **error);

Parses a file containing a GtkBuilder UI definition and merges it with the current contents of `builder` .

Most users will probably want to use `gtk_builder_new_from_file()`.

If an error occurs, 0 will be returned and `error` will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_FILE_ERROR domain.

It’s not really reasonable to attempt to handle failures of this call. You should not use this function with untrusted files (ie: files that are not part of your application). Broken GtkBuilder files can easily crash your program, and it’s possible that memory was leaked leading up to the reported failure. The only reasonable thing to do when an error is detected is to call `g_error()`.

#### Parameters

builder | a GtkBuilder |
filename | the name of the file to parse |
error | return location for an error, or `NULL`. | [allow-none]

#### Returns

A positive value on success, 0 if an error occurred

Since 2.12

### gtk_builder_add_from_resource ()

    guint
    gtk_builder_add_from_resource (GtkBuilder *builder,
                                   const gchar *resource_path,
                                   GError **error);

Parses a resource file containing a GtkBuilder UI definition and merges it with the current contents of `builder` .

Most users will probably want to use `gtk_builder_new_from_resource()`.

If an error occurs, 0 will be returned and `error` will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_RESOURCE_ERROR domain.

It’s not really reasonable to attempt to handle failures of this call. The only reasonable thing to do when an error is detected is to call `g_error()`.

#### Parameters

builder | a GtkBuilder |
resource_path | the path of the resource file to parse |
error | return location for an error, or `NULL`. | [allow-none]

#### Returns

A positive value on success, 0 if an error occurred

Since 3.4

### gtk_builder_add_from_string ()

    guint
    gtk_builder_add_from_string (GtkBuilder *builder,
                                 const gchar *buffer,
                                 gsize length,
                                 GError **error);

Parses a string containing a GtkBuilder UI definition and merges it with the current contents of `builder` .

Most users will probably want to use `gtk_builder_new_from_string()`.

Upon errors 0 will be returned and `error` will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_VARIANT_PARSE_ERROR domain.

It’s not really reasonable to attempt to handle failures of this call. The only reasonable thing to do when an error is detected is to call `g_error()`.

#### Parameters

builder | a GtkBuilder |
buffer | the string to parse |
length | the length of `buffer` (may be -1 if `buffer` is nul-terminated) |
error | return location for an error, or `NULL`. | [allow-none]

#### Returns

A positive value on success, 0 if an error occurred

Since 2.12

### gtk_builder_add_objects_from_file ()

    guint
    gtk_builder_add_objects_from_file (GtkBuilder *builder,
                                       const gchar *filename,
                                       gchar **object_ids,
                                       GError **error);

Parses a file containing a GtkBuilder UI definition building only the requested objects and merges them with the current contents of `builder` .

Upon errors 0 will be returned and `error` will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_FILE_ERROR domain.

If you are adding an object that depends on an object that is not its child (for instance a GtkTreeView that depends on its GtkTreeModel), you have to explicitly list all of them in `object_ids` .

#### Parameters

builder | a GtkBuilder |
filename | the name of the file to parse |
object_ids | nul-terminated array of objects to build. | [array zero-terminated=1][element-type utf8]
error | return location for an error, or `NULL`. | [allow-none]

#### Returns

A positive value on success, 0 if an error occurred

Since 2.14

### gtk_builder_add_objects_from_string ()

    guint
    gtk_builder_add_objects_from_string (GtkBuilder *builder,
                                         const gchar *buffer,
                                         gsize length,
                                         gchar **object_ids,
                                         GError **error);

Parses a string containing a GtkBuilder UI definition building only the requested objects and merges them with the current contents of `builder` .

Upon errors 0 will be returned and `error` will be assigned a GError from the GTK_BUILDER_ERROR or G_MARKUP_ERROR domain.

If you are adding an object that depends on an object that is not its child (for instance a GtkTreeView that depends on its GtkTreeModel), you have to explicitly list all of them in `object_ids` .

#### Parameters

builder | a GtkBuilder |
buffer | the string to parse |
length | the length of `buffer` (may be -1 if `buffer` is nul-terminated) |
object_ids | nul-terminated array of objects to build. | [array zero-terminated=1][element-type utf8]
error | return location for an error, or `NULL`. | [allow-none]

#### Returns

A positive value on success, 0 if an error occurred

Since 2.14

### gtk_builder_add_objects_from_resource ()

    guint
    gtk_builder_add_objects_from_resource (GtkBuilder *builder,
                                           const gchar *resource_path,
                                           gchar **object_ids,
                                           GError **error);

Parses a resource file containing a GtkBuilder UI definition building only the requested objects and merges them with the current contents of `builder` .

Upon errors 0 will be returned and `error` will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_RESOURCE_ERROR domain.

If you are adding an object that depends on an object that is not its child (for instance a GtkTreeView that depends on its GtkTreeModel), you have to explicitly list all of them in `object_ids` .

#### Parameters

builder | a GtkBuilder |
resource_path | the path of the resource file to parse |
object_ids | nul-terminated array of objects to build. | [array zero-terminated=1][element-type utf8]
error | return location for an error, or `NULL`. | [allow-none]

#### Returns

A positive value on success, 0 if an error occurred

Since 3.4

### gtk_builder_get_object ()

    GObject *
    gtk_builder_get_object (GtkBuilder *builder,
                            const gchar *name);

Gets the object named `name` . Note that this function does not increment the reference count of the returned object.

#### Parameters

builder | a GtkBuilder |
name | name of object to get |

#### Returns

the object named `name` or `NULL` if it could not be found in the object tree.

[transfer none]

Since 2.12

### gtk_builder_get_objects ()

    GSList *
    gtk_builder_get_objects (GtkBuilder *builder);

Gets all objects that have been constructed by `builder` . Note that this function does not increment the reference counts of the returned objects.

#### Parameters

builder | a GtkBuilder |

#### Returns

a newly-allocated GSList containing all the objects constructed by the GtkBuilder instance. It should be freed by `g_slist_free()`.

[element-type GObject][transfer container]

Since 2.12

### gtk_builder_expose_object ()

    void
    gtk_builder_expose_object (GtkBuilder *builder,
                               const gchar *name,
                               GObject *object);

Add `object` to the `builder` object pool so it can be referenced just like any other object built by builder.

#### Parameters

builder | a GtkBuilder |
name | the name of the object exposed to the builder |
object | the object to expose |

Since 3.8

### gtk_builder_connect_signals ()

    void
    gtk_builder_connect_signals (GtkBuilder *builder,
                                 gpointer user_data);

This method is a simpler variation of `gtk_builder_connect_signals_full()`. It uses symbols explicitly added to `builder` with prior calls to `gtk_builder_add_callback_symbol()`. In the case that symbols are not explicitly added; it 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 handler names given in the interface description with symbols in the application and connects the signals. Note that this function can only be called once, subsequent calls will do nothing.

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

If you rely on GModule support to lookup callbacks in the symbol table, the following details should be noted:

When compiling applications for Windows, you must declare signal callbacks with G_MODULE_EXPORT, or they will not be put in the symbol table. On Linux and Unices, this is not necessary; applications should instead be compiled with the -Wl,--export-dynamic CFLAGS, and linked against gmodule-export-2.0.

#### Parameters

builder | a GtkBuilder |
user_data | user data to pass back with all signals |

Since 2.12

### gtk_builder_connect_signals_full ()

    void
    gtk_builder_connect_signals_full (GtkBuilder *builder,
                                      GtkBuilderConnectFunc func,
                                      gpointer user_data);

This function can be thought of the interpreted language binding version of `gtk_builder_connect_signals()`, except that it does not require GModule to function correctly.

#### Parameters

builder | a GtkBuilder |
func | the function used to connect the signals. | [scope call]
user_data | arbitrary data that will be passed to the connection function |

Since 2.12

### gtk_builder_set_translation_domain ()

    void
    gtk_builder_set_translation_domain (GtkBuilder *builder,
                                        const gchar *domain);

Sets the translation domain of `builder` . See “translation-domain”.

#### Parameters

builder | a GtkBuilder |
domain | the translation domain or `NULL`. | [allow-none]

Since 2.12

### gtk_builder_get_translation_domain ()

    const gchar *
    gtk_builder_get_translation_domain (GtkBuilder *builder);

Gets the translation domain of `builder` .

#### Parameters

builder | a GtkBuilder |

#### Returns

the translation domain. This string is owned by the builder object and must not be modified or freed.

Since 2.12

### gtk_builder_set_application ()

    void
    gtk_builder_set_application (GtkBuilder *builder,
                                 GtkApplication *application);

Sets the application associated with `builder` .

You only need this function if there is more than one GApplication in your process. `application` cannot be `NULL`.

#### Parameters

builder | a GtkBuilder |
application | a GtkApplication |

Since 3.10

### gtk_builder_get_application ()

    GtkApplication *
    gtk_builder_get_application (GtkBuilder *builder);

Gets the GtkApplication associated with the builder.

The GtkApplication is used for creating action proxies as requested from XML that the builder is loading.

By default, the builder uses the default application: the one from `g_application_get_default()`. If you want to use another application for constructing proxies, use `gtk_builder_set_application()`.

#### Parameters

builder | a GtkBuilder |

#### Returns

the application being used by the builder, or `NULL`.

[transfer none]

Since 3.10

### gtk_builder_get_type_from_name ()

    GType
    gtk_builder_get_type_from_name (GtkBuilder *builder,
                                    const char *type_name);

Looks up a type by name, using the virtual function that GtkBuilder has for that purpose. This is mainly used when implementing the GtkBuildable interface on a type.

#### Parameters

builder | a GtkBuilder |
type_name | type name to lookup |

#### Returns

the GType found for `type_name` or G_TYPE_INVALID if no type was found

Since 2.12

### gtk_builder_value_from_string ()

    gboolean
    gtk_builder_value_from_string (GtkBuilder *builder,
                                   GParamSpec *pspec,
                                   const gchar *string,
                                   GValue *value,
                                   GError **error);

This function demarshals a value from a string. This function calls `g_value_init()` on the `value` argument, so it need not be initialised beforehand.

This function can handle char, uchar, boolean, int, uint, long, ulong, enum, flags, float, double, string, GdkColor, GdkRGBA and GtkAdjustment type values. Support for GtkWidget type values is still to come.

Upon errors `FALSE` will be returned and `error` will be assigned a GError from the GTK_BUILDER_ERROR domain.

#### Parameters

builder | a GtkBuilder |
pspec | the GParamSpec for the property |
string | the string representation of the value |
value | the GValue to store the result in. | [out]
error | return location for an error, or `NULL`. | [allow-none]

#### Returns

`TRUE` on success

Since 2.12

### gtk_builder_value_from_string_type ()

    gboolean
    gtk_builder_value_from_string_type (GtkBuilder *builder,
                                        GType type,
                                        const gchar *string,
                                        GValue *value,
                                        GError **error);

Like `gtk_builder_value_from_string()`, this function demarshals a value from a string, but takes a GType instead of GParamSpec. This function calls `g_value_init()` on the `value` argument, so it need not be initialised beforehand.

Upon errors `FALSE` will be returned and `error` will be assigned a GError from the GTK_BUILDER_ERROR domain.

#### Parameters

builder | a GtkBuilder |
type | the GType of the value |
string | the string representation of the value |
value | the GValue to store the result in. | [out]
error | return location for an error, or `NULL`. | [allow-none]

#### Returns

`TRUE` on success

Since 2.12

### GTK_BUILDER_WARN_INVALID_CHILD_TYPE()

    #define             GTK_BUILDER_WARN_INVALID_CHILD_TYPE(object, type)

This macro should be used to emit a warning about and unexpected `type` value in a GtkBuildable add_child implementation.

#### Parameters

object | the GtkBuildable on which the warning ocurred |
type | the unexpected type value |

### GTK_BUILDER_ERROR

    #define GTK_BUILDER_ERROR                (gtk_builder_error_quark ())

## Types and Values

### GtkBuilder

    typedef struct _GtkBuilder GtkBuilder;

### enum GtkBuilderError

Error codes that identify various errors that can occur while using GtkBuilder.

#### Members

GTK_BUILDER_ERROR_INVALID_TYPE_FUNCTION | A type-func attribute didn’t name a function that returns a GType. |
GTK_BUILDER_ERROR_UNHANDLED_TAG | The input contained a tag that GtkBuilder can’t handle. |
GTK_BUILDER_ERROR_MISSING_ATTRIBUTE | An attribute that is required by GtkBuilder was missing. |
GTK_BUILDER_ERROR_INVALID_ATTRIBUTE | GtkBuilder found an attribute that it doesn’t understand. |
GTK_BUILDER_ERROR_INVALID_TAG | GtkBuilder found a tag that it doesn’t understand. |
GTK_BUILDER_ERROR_MISSING_PROPERTY_VALUE | A required property value was missing. |
GTK_BUILDER_ERROR_INVALID_VALUE | GtkBuilder couldn’t parse some attribute value. |
GTK_BUILDER_ERROR_VERSION_MISMATCH | The input file requires a newer version of GTK+. |
GTK_BUILDER_ERROR_DUPLICATE_ID | An object id occurred twice. |
GTK_BUILDER_ERROR_OBJECT_TYPE_REFUSED | A specified object type is of the same type or derived from the type of the composite class being extended with builder XML. |
GTK_BUILDER_ERROR_TEMPLATE_MISMATCH | The wrong type was specified in a composite class’s template XML |
GTK_BUILDER_ERROR_INVALID_PROPERTY | The specified property is unknown for the object class. |
GTK_BUILDER_ERROR_INVALID_SIGNAL | The specified signal is unknown for the object class. |

## Property Details

### The `“translation-domain”` property

      “translation-domain”       gchar *

The translation domain used when translating property values that have been marked as translatable in interface descriptions. If the translation domain is `NULL`, GtkBuilder uses `gettext()`, otherwise `g_dgettext()`.

Flags: Read / Write

Default value: NULL

Since 2.12