Creates a new empty builder object.
This function is only useful if you intend to make multiple calls
to [methodGtk
.Builder.add_from_file], [methodGtk
.Builder.add_from_resource]
or [methodGtk
.Builder.add_from_string] in order to merge multiple UI
descriptions into a single builder.
The object the builder is evaluating for.
The scope the builder is operating in
The translation domain used when translating property values that have been marked as translatable.
If the translation domain is %NULL, GtkBuilder
uses gettext(),
otherwise g_dgettext().
Parses a file containing a UI definition and merges it with
the current contents of builder
.
This function is useful if you need to call
[methodGtk
.Builder.set_current_object]) to add user data to
callbacks before loading GtkBuilder UI. Otherwise, you probably
want [ctorGtk
.Builder.new_from_file] instead.
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
domains.
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()
.
the name of the file to parse
Parses a resource file containing a UI definition
and merges it with the current contents of builder
.
This function is useful if you need to call
[methodGtk
.Builder.set_current_object] to add user data to
callbacks before loading GtkBuilder UI. Otherwise, you probably
want [ctorGtk
.Builder.new_from_resource] instead.
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().
the path of the resource file to parse
Parses a string containing a UI definition and merges it
with the current contents of builder
.
This function is useful if you need to call
[methodGtk
.Builder.set_current_object] to add user data to
callbacks before loading GtkBuilder
UI. Otherwise, you probably
want [ctorGtk
.Builder.new_from_string] instead.
Upon errors %FALSE 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().
the string to parse
the length of buffer
(may be -1 if buffer
is nul-terminated)
Parses a file containing a 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
.
the name of the file to parse
nul-terminated array of objects to build
Parses a resource file containing a 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
.
the path of the resource file to parse
nul-terminated array of objects to build
Parses a string containing a UI definition, building only the
requested objects and merges them with the current contents of
builder
.
Upon errors %FALSE 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
.
the string to parse
the length of buffer
(may be -1 if buffer
is nul-terminated)
nul-terminated array of objects to build
Creates a binding between source_property
on source
and target_property
on target
.
Whenever the source_property
is changed the target_property
is
updated using the same value. For instance:
g_object_bind_property (action, "active", widget, "sensitive", 0);
Will result in the "sensitive" property of the widget #GObject instance to be updated with the same value of the "active" property of the action #GObject instance.
If flags
contains %G_BINDING_BIDIRECTIONAL then the binding will be mutual:
if target_property
on target
changes then the source_property
on source
will be updated as well.
The binding will automatically be removed when either the source
or the
target
instances are finalized. To remove the binding without affecting the
source
and the target
you can just call g_object_unref() on the returned
#GBinding instance.
Removing the binding by calling g_object_unref() on it must only be done if
the binding, source
and target
are only used from a single thread and it
is clear that both source
and target
outlive the binding. Especially it
is not safe to rely on this if the binding, source
or target
can be
finalized from different threads. Keep another reference to the binding and
use g_binding_unbind() instead to be on the safe side.
A #GObject can have multiple bindings.
the property on source
to bind
the target #GObject
the property on target
to bind
flags to pass to #GBinding
Creates a binding between source_property
on source
and target_property
on target,
allowing you to set the transformation functions to be used by
the binding.
This function is the language bindings friendly version of g_object_bind_property_full(), using #GClosures instead of function pointers.
the property on source
to bind
the target #GObject
the property on target
to bind
flags to pass to #GBinding
a #GClosure wrapping the transformation function from the source
to the target,
or %NULL to use the default
a #GClosure wrapping the transformation function from the target
to the source,
or %NULL to use the default
Creates a closure to invoke the function called function_name
.
This is using the create_closure() implementation of builder'
s
[ifaceGtk
.BuilderScope].
If no closure could be created, %NULL will be returned and error
will be set.
name of the function to look up
closure creation flags
Object to create the closure with
Main private entry point for building composite components from template XML.
This is exported purely to let gtk-builder-tool
validate
templates, applications have no need to call this function.
the object that is being extended
the type that the template is for
the string to parse
the length of buffer
(may be -1 if buffer
is nul-terminated)
This function is intended for #GObject implementations to re-enforce a [floating][floating-ref] object reference. Doing this is seldom required: all #GInitiallyUnowneds are created with a floating reference which usually just needs to be sunken by calling g_object_ref_sink().
Increases the freeze count on object
. If the freeze count is
non-zero, the emission of "notify" signals on object
is
stopped. The signals are queued until the freeze count is decreased
to zero. Duplicate notifications are squashed so that at most one
#GObject::notify signal is emitted for each property modified while the
object is frozen.
This is necessary for accessors that modify multiple properties to prevent premature notification while the object is still being modified.
Gets a named field from the objects table of associations (see g_object_set_data()).
name of the key for that association
Gets a property of an object.
The value
can be:
In general, a copy is made of the property contents and the caller is responsible for freeing the memory by calling g_value_unset().
Note that g_object_get_property() is really intended for language bindings, g_object_get() is much more convenient for C programming.
the name of the property to get
return location for the property value
This function gets back user data pointers stored via g_object_set_qdata().
A #GQuark, naming the user data pointer
Gets the scope in use that was set via gtk_builder_set_scope().
Gets the translation domain of builder
.
Looks up a type by name.
This is using the virtual function that GtkBuilder
has
for that purpose. This is mainly used when implementing
the GtkBuildable
interface on a type.
type name to lookup
Gets n_properties
properties for an object
.
Obtained properties will be set to values
. All properties must be valid.
Warnings will be emitted and undefined behaviour may result if invalid
properties are passed in.
the names of each property to get
the values of each property to get
Checks whether object
has a [floating][floating-ref] reference.
Emits a "notify" signal for the property property_name
on object
.
When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.
Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.
the name of a property installed on the class of object
.
Emits a "notify" signal for the property specified by pspec
on object
.
This function omits the property name lookup, hence it is faster than g_object_notify().
One way to avoid using g_object_notify() from within the class that registered the properties, and using g_object_notify_by_pspec() instead, is to store the GParamSpec used with g_object_class_install_property() inside a static array, e.g.:
enum
{
PROP_0,
PROP_FOO,
PROP_LAST
};
static GParamSpec *properties[PROP_LAST];
static void
my_object_class_init (MyObjectClass *klass)
{
properties[PROP_FOO] = g_param_spec_int ("foo", "Foo", "The foo",
0, 100,
50,
G_PARAM_READWRITE);
g_object_class_install_property (gobject_class,
PROP_FOO,
properties[PROP_FOO]);
}
and then notify a change on the "foo" property with:
g_object_notify_by_pspec (self, properties[PROP_FOO]);
the #GParamSpec of a property installed on the class of object
.
Increase the reference count of object,
and possibly remove the
[floating][floating-ref] reference, if object
has a floating reference.
In other words, if the object is floating, then this call "assumes ownership" of the floating reference, converting it to a normal reference by clearing the floating flag while leaving the reference count unchanged. If the object is not floating, then this call adds a new normal reference increasing the reference count by one.
Since GLib 2.56, the type of object
will be propagated to the return type
under the same conditions as for g_object_ref().
Releases all references to other objects. This can be used to break reference cycles.
This function should only be called from object system implementations.
Sets the current object for the builder
.
The current object can be thought of as the this
object that the
builder is working for and will often be used as the default object
when an object is optional.
[methodGtk
.Widget.init_template] for example will set the current
object to the widget the template is inited for. For functions like
[ctorGtk
.Builder.new_from_resource], the current object will be %NULL.
Each object carries around a table of associations from strings to pointers. This function lets you set an association.
If the object already had an association with that name, the old association will be destroyed.
Internally, the key
is converted to a #GQuark using g_quark_from_string().
This means a copy of key
is kept permanently (even after object
has been
finalized) — so it is recommended to only use a small, bounded set of values
for key
in your program, to avoid the #GQuark storage growing unbounded.
name of the key
data to associate with that key
Sets a property on an object.
the name of the property to set
the value
Sets the scope the builder should operate in.
If scope
is %NULL, a new [classGtk
.BuilderCScope] will be created.
the scope to use
Sets the translation domain of builder
.
the translation domain
Remove a specified datum from the object's data associations, without invoking the association's destroy handler.
name of the key
This function gets back user data pointers stored via
g_object_set_qdata() and removes the data
from object
without invoking its destroy() function (if any was
set).
Usually, calling this function is only required to update
user data pointers with a destroy notifier, for example:
void
object_add_to_user_list (GObject *object,
const gchar *new_string)
{
// the quark, naming the object data
GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
// retrieve the old string list
GList *list = g_object_steal_qdata (object, quark_string_list);
// prepend new string
list = g_list_prepend (list, g_strdup (new_string));
// this changed 'list', so we need to set it again
g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
}
static void
free_string_list (gpointer data)
{
GList *node, *list = data;
for (node = list; node; node = node->next)
g_free (node->data);
g_list_free (list);
}
Using g_object_get_qdata() in the above example, instead of g_object_steal_qdata() would have left the destroy function set, and thus the partial string list would have been freed upon g_object_set_qdata_full().
A #GQuark, naming the user data pointer
Reverts the effect of a previous call to
g_object_freeze_notify(). The freeze count is decreased on object
and when it reaches zero, queued "notify" signals are emitted.
Duplicate notifications for each property are squashed so that at most one #GObject::notify signal is emitted for each property, in the reverse order in which they have been queued.
It is an error to call this function when the freeze count is zero.
Decreases the reference count of object
. When its reference count
drops to 0, the object is finalized (i.e. its memory is freed).
If the pointer to the #GObject may be reused in future (for example, if it is an instance variable of another object), it is recommended to clear the pointer to %NULL rather than retain a dangling pointer to a potentially invalid #GObject instance. Use g_clear_object() for this.
Demarshals a value from a string.
This function calls g_value_init() on the value
argument,
so it need not be initialised beforehand.
Can handle char, uchar, boolean, int, uint, long,
ulong, enum, flags, float, double, string, GdkRGBA
and
GtkAdjustment
type values.
Upon errors %FALSE will be returned and error
will be
assigned a GError
from the %GTK_BUILDER_ERROR domain.
the GParamSpec
for the property
the string representation of the value
Demarshals a value from a string.
Unlike [methodGtk
.Builder.value_from_string], this function
takes a GType
instead of GParamSpec
.
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.
the GType
of the value
the string representation of the value
This function essentially limits the life time of the closure
to
the life time of the object. That is, when the object is finalized,
the closure
is invalidated by calling g_closure_invalidate() on
it, in order to prevent invocations of the closure with a finalized
(nonexisting) object. Also, g_object_ref() and g_object_unref() are
added as marshal guards to the closure,
to ensure that an extra
reference count is held on object
during invocation of the
closure
. Usually, this function will be called on closures that
use this object
as closure data.
#GClosure to watch
Find the #GParamSpec with the given name for an
interface. Generally, the interface vtable passed in as g_iface
will be the default vtable from g_type_default_interface_ref(), or,
if you know the interface has already been loaded,
g_type_default_interface_peek().
any interface vtable for the interface, or the default vtable for the interface
name of a property to look up.
Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created #GParamSpec, but normally g_object_class_override_property() will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.
This function is meant to be called from the interface's default
vtable initialization function (the class_init
member of
#GTypeInfo.) It must not be called after after class_init
has
been called for any object types implementing this interface.
If pspec
is a floating reference, it will be consumed.
any interface vtable for the interface, or the default vtable for the interface.
the #GParamSpec for the new property
Lists the properties of an interface.Generally, the interface
vtable passed in as g_iface
will be the default vtable from
g_type_default_interface_ref(), or, if you know the interface has
already been loaded, g_type_default_interface_peek().
any interface vtable for the interface, or the default vtable for the interface
Creates a new empty builder object.
This function is only useful if you intend to make multiple calls
to [methodGtk
.Builder.add_from_file], [methodGtk
.Builder.add_from_resource]
or [methodGtk
.Builder.add_from_string] in order to merge multiple UI
descriptions into a single builder.
Parses the 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.
filename of user interface description file
Parses the UI definition in string
.
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.
a user interface (XML) description
the length of string,
or -1
Creates a new instance of a #GObject subtype and sets its properties.
Construction parameters (see %G_PARAM_CONSTRUCT, %G_PARAM_CONSTRUCT_ONLY) which are not explicitly specified are set to their default values.
the type id of the #GObject subtype to instantiate
an array of #GParameter
A
GtkBuilder
reads XML descriptions of a user interface and instantiates the described objects.To create a
GtkBuilder
from a user interface description, call [ctorGtk
.Builder.new_from_file], [ctorGtk
.Builder.new_from_resource] or [ctorGtk
.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 [ctorGtk
.Builder.new] to get an empty builder and populate it by (multiple) calls to [methodGtk
.Builder.add_from_file], [methodGtk
.Builder.add_from_resource] or [methodGtk
.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 [methodGtk
.Window.destroy] to get rid of them and all the widgets they contain.The functions [method
Gtk
.Builder.get_object] and [methodGtk
.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 [methodGtk
.Window.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.GtkBuilder UI Definitions
GtkBuilder
parses textual descriptions of user interfaces which are specified in XML format. We refer to these descriptions as “GtkBuilder UI definitions” or just “UI definitions” if the context is clear.The toplevel element is
<interface>
. It optionally takes a “domain” attribute, which will make the builder look for translated strings usingdgettext()
in the domain specified. This can also be done by calling [methodGtk
.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>
”.GtkBuilder
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 theget_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 theget_type()
function explicitly with the "type-func" attribute.Objects may be given a name with the “id” attribute, which allows the application to retrieve them from the builder with [method
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___
(three consecutive 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 usesgettext()
(ordgettext()
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_INPUT_HINT_EMOJI|GTK_INPUT_HINT_LOWERCASE”) and colors (in a format understood by [methodGdk
.RGBA.parse]).GVariant
s can be specified in the format understood by g_variant_parse(), and 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 [method
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, and optionally, "bind-property" and "bind-flags" to specify the source property and source binding flags respectively. Internally,
GtkBuilder
implements this usingGBinding
objects. For more information see g_object_bind_property().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 content area of a
GtkDialog
). This can be achieved by setting the “internal-child” property of the<child>
element to a true value. Note thatGtkBuilder
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.Signal handlers and function pointers
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. 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.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 Unix, this is not necessary; applications should instead be compiled with the -Wl,--export-dynamic
CFLAGS
, and linked againstgmodule-export-2.0
.A GtkBuilder UI Definition
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 element gets parsed by
the custom tag handler of the parent object, while a custom element in
an
These XML fragments are explained in the documentation of the respective objects.
A
<template>
tag can be used to define a widget class’s components. See the GtkWidget documentation for details.