Optionalproperties: Partial<Gio.Settings.ConstructorProps>Internal$signalsCompile-time signal type information.
This instance property is generated only for TypeScript type checking. It is not defined at runtime and should not be accessed in JS code.
Static$gtypeConstruct OnlybackendThe name of the context that the settings are stored in.
Read-OnlySince 2.28delay_Read-OnlySince 2.28delayRead-Onlyhas_Whether the Gio.Settings object has outstanding changes.
These changes will be applied when Gio.Settings.apply is called.
Read-OnlyhasWhether the Gio.Settings object has outstanding changes.
These changes will be applied when Gio.Settings.apply is called.
Construct OnlypathThe path within the backend where the settings are stored.
Construct OnlyschemaThe name of the schema that describes the types of keys for this Gio.Settings object.
The type of this property is not Gio.SettingsSchema. Gio.SettingsSchema has only existed since version 2.32 and unfortunately this name was used in previous versions to refer to the schema ID rather than the schema itself. Take care to use the Gio.Settings.settings_schema property if you wish to pass in a Gio.SettingsSchema.
since 2.32: Use the Gio.Settings.schema_id property instead. In a future version, this property may instead refer to a Gio.SettingsSchema.
Construct Onlyschema_The name of the schema that describes the types of keys for this Gio.Settings object.
Construct OnlyschemaThe name of the schema that describes the types of keys for this Gio.Settings object.
Construct Onlysettings_The Gio.SettingsSchema describing the types of keys for this Gio.Settings object.
Ideally, this property would be called Gio.Settings.schema. Gio.SettingsSchema has only existed since version 2.32, however, and before then the Gio.Settings.schema property was used to refer to the ID of the schema rather than the schema itself. Take care.
Construct OnlysettingsThe Gio.SettingsSchema describing the types of keys for this Gio.Settings object.
Ideally, this property would be called Gio.Settings.schema. Gio.SettingsSchema has only existed since version 2.32, however, and before then the Gio.Settings.schema property was used to refer to the ID of the schema rather than the schema itself. Take care.
Applies any changes that have been made to the settings.
This function does nothing unless settings is in
‘delay-apply’ mode. In the normal
case settings are always applied immediately.
Create a binding between the key in the settings object
and the property property of object.
The binding uses the default GIO mapping functions to map between the settings and property values. These functions handle booleans, numeric types and string types in a straightforward way. Use Gio.Settings.bind_with_mapping if you need a custom mapping, or map between types that are not supported by the default mapping functions.
Unless the flags include Gio.SettingsBindFlags.NO_SENSITIVITY, this
function also establishes a binding between the writability of
key and the sensitive property of object (if object has
a boolean property by that name). See Gio.Settings.bind_writable
for more details about writable bindings.
Note that the lifecycle of the binding is tied to object,
and that you can have only one binding per object property.
If you bind the same property twice on the same object, the second
binding overrides the first one.
the key to bind
the object with property to bind
the name of the property to bind
flags for the binding
Version of Gio.Settings.bind_with_mapping using closures instead of callbacks for easier binding in other languages.
the key to bind
the object with property to bind
the name of the property to bind
flags for the binding
Optionalget_mapping: Closure<any, any>a function that gets called to convert values from settings to object, or NULL to use the default GIO mapping
Optionalset_mapping: Closure<any, any>a function that gets called to convert values from object to settings, or NULL to use the default GIO mapping
Create a binding between the writability of key in the
settings object and the property property of object.
The property must be boolean; sensitive or visible
properties of widgets are the most likely candidates.
Writable bindings are always uni-directional; changes of the writability of the setting will be propagated to the object property, not the other way.
When the inverted argument is true, the binding inverts the
value as it passes from the setting to the object, i.e. property
will be set to true if the key is not writable.
Note that the lifecycle of the binding is tied to object,
and that you can have only one binding per object property.
If you bind the same property twice on the same object, the second
binding overrides the first one.
SignalconnectSignalconnect_Creates a Gio.Action corresponding to a given Gio.Settings key.
The action has the same name as the key.
The value of the key becomes the state of the action and the action is enabled when the key is writable. Changing the state of the action results in the key being written to. Changes to the value or writability of the key cause appropriate change notifications to be emitted for the action.
For boolean-valued keys, action activations take no parameter and result in the toggling of the value. For all other types, activations take the new value for the key (which must have the correct type).
the name of a key in settings
a new Gio.Action
Changes the Gio.Settings object into ‘delay-apply’ mode.
In this
mode, changes to settings are not immediately propagated to the
backend, but kept locally until Gio.Settings.apply is called.
SignalemitGets the value that is stored at key in settings.
A convenience variant of Gio.Settings.get for booleans.
It is a programmer error to give a key that isn’t specified as
having a b type in the schema for settings (see GLib.VariantType).
the key to get the value for
a boolean
Creates a child settings object which has a base path of
base-path/name, where base-path is the base path of
settings and name is as specified by the caller.
The schema for the child settings object must have been declared
in the schema of settings using a <child> element.
The created child settings object will inherit the
Gio.Settings.delay_apply mode from settings.
the name of the child schema
a ‘child’ settings object
Gets the ‘default value’ of a key.
This is the value that would be read if Gio.Settings.reset were to be called on the key.
Note that this may be a different value than returned by Gio.SettingsSchemaKey.get_default_value if the system administrator has provided a default value.
Comparing the return values of Gio.Settings.get_default_value and Gio.Settings.get_value is not sufficient for determining if a value has been set because the user may have explicitly set the value to something that happens to be equal to the default. The difference here is that if the default changes in the future, the user’s key will still be set.
This function may be useful for adding an indication to a UI of what the default value was before the user set it.
It is a programmer error to give a key that isn’t contained in the
schema for settings.
the key to get the default value for
the default value
Gets the value that is stored at key in settings.
A convenience variant of Gio.Settings.get for doubles.
It is a programmer error to give a key that isn’t specified as
having a d type in the schema for settings (see GLib.VariantType).
the key to get the value for
a double
Gets the value that is stored in settings for key and converts it
to the enum value that it represents.
In order to use this function the type of the value must be a string and it must be marked in the schema file as an enumerated type.
It is a programmer error to give a key that isn’t contained in the
schema for settings or is not marked as an enumerated type.
If the value stored in the configuration database is not a valid value for the enumerated type then this function will return the default value.
the key to get the value for
the enum value
Gets the value that is stored in settings for key and converts it
to the flags value that it represents.
In order to use this function the type of the value must be an array of strings and it must be marked in the schema file as a flags type.
It is a programmer error to give a key that isn’t contained in the
schema for settings or is not marked as a flags type.
If the value stored in the configuration database is not a valid value for the flags type then this function will return the default value.
the key to get the value for
the flags value
Returns whether the Gio.Settings object has any unapplied changes.
This can only be the case if it is in ‘delay-apply’ mode.
true if settings has unapplied changes, false otherwise
Gets the value that is stored at key in settings.
A convenience variant of Gio.Settings.get for 32-bit integers.
It is a programmer error to give a key that isn’t specified as
having an i type in the schema for settings (see GLib.VariantType).
the key to get the value for
an integer
Gets the value that is stored at key in settings.
A convenience variant of Gio.Settings.get for 64-bit integers.
It is a programmer error to give a key that isn’t specified as
having an x type in the schema for settings (see GLib.VariantType).
the key to get the value for
a 64-bit integer
Gets the value that is stored at key in settings, subject to
application-level validation/mapping.
You should use this function when the application needs to perform
some processing on the value of the key (for example, parsing). The
mapping function performs that processing. If the function
indicates that the processing was unsuccessful (due to a parse error,
for example) then the mapping is tried again with another value.
This allows a robust ‘fall back to defaults’ behaviour to be implemented somewhat automatically.
The first value that is tried is the user’s setting for the key. If the mapping function fails to map this value, other values may be tried in an unspecified order (system or site defaults, translated schema default values, untranslated schema default values, etc).
If the mapping function fails for all possible values, one additional
attempt is made: the mapping function is called with a NULL value.
If the mapping function still indicates failure at this point then
the application will be aborted.
The result parameter for the mapping function is pointed to a
gpointer which is initially set to NULL. The same pointer is given
to each invocation of mapping. The final value of that gpointer is
what is returned by this function. NULL is valid; it is returned
just as any other value would be.
the key to get the value for
the function to map the value in the settings database to the value used by the application
the result, which may be NULL
Gets the value that is stored at key in settings.
A convenience variant of Gio.Settings.get for strings.
It is a programmer error to give a key that isn’t specified as
having an s type in the schema for settings (see GLib.VariantType).
the key to get the value for
a newly-allocated string
A convenience variant of Gio.Settings.get for string arrays.
It is a programmer error to give a key that isn’t specified as
having an as type in the schema for settings (see GLib.VariantType).
the key to get the value for
a newly-allocated, NULL-terminated array of strings, the value that is stored at key in settings.
Gets the value that is stored at key in settings.
A convenience variant of Gio.Settings.get for 32-bit unsigned integers.
It is a programmer error to give a key that isn’t specified as
having a u type in the schema for settings (see GLib.VariantType).
the key to get the value for
an unsigned integer
Gets the value that is stored at key in settings.
A convenience variant of Gio.Settings.get for 64-bit unsigned integers.
It is a programmer error to give a key that isn’t specified as
having a t type in the schema for settings (see GLib.VariantType).
the key to get the value for
a 64-bit unsigned integer
Checks the ‘user value’ of a key, if there is one.
The user value of a key is the last value that was set by the user.
After calling Gio.Settings.reset this function should always return
NULL (assuming something is not wrong with the system
configuration).
It is possible that Gio.Settings.get_value will return a different value than this function. This can happen in the case that the user set a value for a key that was subsequently locked down by the system administrator — this function will return the user’s old value.
This function may be useful for adding a ‘reset’ option to a UI or for providing indication that a particular value has been changed.
It is a programmer error to give a key that isn’t contained in the
schema for settings.
the key to get the user value for
the user’s value, if set
Gets the value that is stored in settings for key.
It is a programmer error to give a key that isn’t contained in the
schema for settings.
the key to get the value for
a new GLib.Variant
Finds out if a key can be written.
the name of a key
true if the key name is writable, false otherwise
Gets the list of children on settings.
The list is exactly the list of strings for which it is not an error to call Gio.Settings.get_child.
There is little reason to call this function from ‘normal’ code, since you should already know what children are in your schema. This function may still be useful there for introspection reasons, however.
You should free the return value with GLib.strfreev when you are done with it.
a list of the children on settings, in no defined order
Introspects the list of keys on settings.
You should probably not be calling this function from ‘normal’ code (since you should already know what keys are in your schema). This function is intended for introspection reasons.
You should free the return value with GLib.strfreev when you are done with it.
a list of the keys on settings, in no defined order
Resets key to its default value.
This call resets the key, as much as possible, to its default value. That might be the value specified in the schema or the one set by the administrator.
the name of a key
Reverts all unapplied changes to the settings.
This function does nothing unless settings is in
‘delay-apply’ mode. In the normal
case settings are always applied immediately.
Change notifications will be emitted for affected keys.
Sets key in settings to value.
A convenience variant of Gio.Settings.set for booleans.
It is a programmer error to give a key that isn’t specified as
having a b type in the schema for settings (see GLib.VariantType).
the key to set the value for
the value to set it to
true if setting the key succeeded, false if the key was not writable
Sets key in settings to value.
A convenience variant of Gio.Settings.set for doubles.
It is a programmer error to give a key that isn’t specified as
having a d type in the schema for settings (see GLib.VariantType).
the key to set the value for
the value to set it to
true if setting the key succeeded, false if the key was not writable
Looks up the enumerated type nick for value and writes it to key,
within settings.
It is a programmer error to give a key that isn’t contained in the
schema for settings or is not marked as an enumerated type, or for
value not to be a valid value for the named type.
After performing the write, accessing key directly with
Gio.Settings.get_string will return the ‘nick’ associated with
value.
the key to set the value for
an enumerated value
true if the set succeeds, false otherwise
Looks up the flags type nicks for the bits specified by value, puts
them in an array of strings and writes the array to key, within
settings.
It is a programmer error to give a key that isn’t contained in the
schema for settings or is not marked as a flags type, or for value
to contain any bits that are not value for the named type.
After performing the write, accessing key directly with
Gio.Settings.get_strv will return an array of ‘nicks’; one for each
bit in value.
the key to set the value for
a flags value
true if the set succeeds, false otherwise
Sets key in settings to value.
A convenience variant of Gio.Settings.set for 32-bit integers.
It is a programmer error to give a key that isn’t specified as
having an i type in the schema for settings (see GLib.VariantType).
the key to set the value for
the value to set it to
true if setting the key succeeded, false if the key was not writable
Sets key in settings to value.
A convenience variant of Gio.Settings.set for 64-bit integers.
It is a programmer error to give a key that isn’t specified as
having an x type in the schema for settings (see GLib.VariantType).
the key to set the value for
the value to set it to
true if setting the key succeeded, false if the key was not writable
Sets key in settings to value.
A convenience variant of Gio.Settings.set for strings.
It is a programmer error to give a key that isn’t specified as
having an s type in the schema for settings (see GLib.VariantType).
the key to set the value for
the value to set it to
true if setting the key succeeded, false if the key was not writable
Sets key in settings to value.
A convenience variant of Gio.Settings.set for string arrays. If
value is NULL, then key is set to be the empty array.
It is a programmer error to give a key that isn’t specified as
having an as type in the schema for settings (see GLib.VariantType).
the key to set the value for
Optionalvalue: string[]the value to set it to
true if setting the key succeeded, false if the key was not writable
Sets key in settings to value.
A convenience variant of Gio.Settings.set for 32-bit unsigned integers.
It is a programmer error to give a key that isn’t specified as
having a u type in the schema for settings (see GLib.VariantType).
the key to set the value for
the value to set it to
true if setting the key succeeded, false if the key was not writable
Sets key in settings to value.
A convenience variant of Gio.Settings.set for 64-bit unsigned integers.
It is a programmer error to give a key that isn’t specified as
having a t type in the schema for settings (see GLib.VariantType).
the key to set the value for
the value to set it to
true if setting the key succeeded, false if the key was not writable
Sets key in settings to value.
It is a programmer error to give a key that isn’t contained in the
schema for settings or for value to have the incorrect type, per
the schema.
If value is floating then this function consumes the reference.
the key to set the value for
a GLib.Variant of the correct type
true if setting the key succeeded, false if the key was not writable
Virtualvfunc_Virtualvfunc_Virtualvfunc_Virtualvfunc_Staticlist_Deprecated.
Staticlist_Deprecated.
StaticnewStaticnew_Optionalbackend: Gio.SettingsBackendOptionalpath: stringStaticnew_Staticnew_Staticnew_StaticsyncEnsures that all pending operations are complete for the default backend.
Writes made to a Gio.Settings are handled asynchronously. For this reason, it is very unlikely that the changes have it to disk by the time Gio.Settings.set returns.
This call will block until all of the writes have made it to the backend. Since the main loop is not running, no change notifications will be dispatched during this call (but some may be queued by the time the call is done).
StaticunbindRemoves an existing binding for property on object.
Note that bindings are automatically removed when the object is finalized, so it is rarely necessary to call this function.
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.Object instance to be updated with the same value of the "active" property of the action GObject.Object instance.
If flags contains GObject.BindingFlags.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
GObject.Binding 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.Object can have multiple bindings.
the property on source to bind
the target GObject.Object
the property on target to bind
flags to pass to GObject.Binding
the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.
Complete version of g_object_bind_property().
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.
If flags contains GObject.BindingFlags.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 transform_from function is only used in case
of bidirectional bindings, otherwise it will be ignored
The binding will automatically be removed when either the source or the
target instances are finalized. This will release the reference that is
being held on the GObject.Binding instance; if you want to hold on to the
GObject.Binding instance, you will need to hold a reference to it.
To remove the binding, call g_binding_unbind().
A GObject.Object can have multiple bindings.
The same user_data parameter will be used for both transform_to
and transform_from transformation functions; the notify function will
be called once, when the binding is removed. If you need different data
for each transformation function, please use
g_object_bind_property_with_closures() instead.
the property on source to bind
the target GObject.Object
the property on target to bind
flags to pass to GObject.Binding
Optionaltransform_to: BindingTransformFuncthe transformation function from the source to the target, or null to use the default
Optionaltransform_from: BindingTransformFuncthe transformation function from the target to the source, or null to use the default
Optionalnotify: DestroyNotifya function to call when disposing the binding, to free resources used by the transformation functions, or null if not required
the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.
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.Object
the property on target to bind
flags to pass to GObject.Binding
a GObject.Closure wrapping the transformation function from the source to the target, or null to use the default
a GObject.Closure wrapping the transformation function from the target to the source, or null to use the default
the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.
Blocks a handler of an instance so it will not be called during any signal emissions
Handler ID of the handler to be blocked
Disconnects a handler from an instance so it will not be called during any future or currently ongoing emissions of the signal it has been connected to.
Handler ID of the handler to be disconnected
This function is intended for GObject.Object 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.Object::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
the data if found, or null if no such data exists.
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 GObject.Value.unset.
Note that GObject.Object.get_property is really intended for language bindings, GObject.Object.get is much more convenient for C programming.
The name of the property to get
Return location for the property value. Can be an empty GObject.Value initialized by G_VALUE_INIT (auto-initialized with expected type since GLib 2.60), a GObject.Value initialized with the expected property type, or a GObject.Value initialized with a transformable type
This function gets back user data pointers stored via
g_object_set_qdata().
A GLib.Quark, naming the user data pointer
The user data pointer set, or null
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.
true if object has a floating 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.:
typedef enum
{
PROP_FOO = 1,
PROP_LAST
} MyObjectProperty;
static GParamSpec *properties[PROP_LAST];
static void
my_object_class_init (MyObjectClass *klass)
{
properties[PROP_FOO] = g_param_spec_int ("foo", NULL, NULL,
0, 100,
50,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
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 GObject.ParamSpec of a property installed on the class of object.
Increases the reference count of object.
Since GLib 2.56, if GLIB_VERSION_MAX_ALLOWED is 2.56 or greater, the type
of object will be propagated to the return type (using the GCC typeof()
extension), so any casting the caller needs to do on the return type must be
explicit.
the same 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().
object
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 multiple properties of an object at once. The properties argument should be a dictionary mapping property names to values.
Object containing the properties to set
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 GLib.Quark 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 GLib.Quark storage growing unbounded.
name of the key
Optionaldata: anydata to associate with that key
Sets a property on an object.
The name of the property to set
The value to set the property to
Remove a specified datum from the object's data associations, without invoking the association's destroy handler.
name of the key
the data if found, or null if no such data exists.
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 GLib.Quark, naming the user data pointer
The user data pointer set, or null
Stops a signal's emission by the given signal name. This will prevent the default handler and any subsequent signal handlers from being invoked.
Name of the signal to stop emission of
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.Object::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.
Unblocks a handler so it will be called again during any signal emissions
Handler ID of the handler to be unblocked
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.Object 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.Object instance. Use g_clear_object() for this.
Virtualvfunc_the constructed function is called by g_object_new() as the
final step of the object creation process. At the point of the call, all
construction properties have been set on the object. The purpose of this
call is to allow for object initialisation steps that can only be performed
after construction properties have been set. constructed implementors
should chain up to the constructed call of their parent class to allow it
to complete its initialisation.
Virtualvfunc_Virtualvfunc_the dispose function is supposed to drop all references to other
objects, but keep the instance otherwise intact, so that client method
invocations still work. It may be run multiple times (due to reference
loops). Before returning, dispose should chain up to the dispose method
of the parent class.
Virtualvfunc_instance finalization function, should finish the finalization of
the instance begun in dispose and chain up to the finalize method of the
parent class.
Virtualvfunc_Virtualvfunc_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.
Virtualvfunc_the generic setter for all properties of this type. Should be
overridden for every type with properties. If implementations of
set_property don't emit property change notification explicitly, this will
be done implicitly by the type system. However, if the notify signal is
emitted explicitly, the type system will not emit it a second time.
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.
GObject.Closure to watch
Static_Staticcompat_Optionaldata: anyStaticfind_Staticinstall_Staticinstall_the id for the new property
the GObject.ParamSpec for the new property
Staticinterface_Find the GObject.ParamSpec 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.
Staticinterface_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 GObject.ParamSpec, 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
GObject.TypeInfo.) 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 GObject.ParamSpec for the new property
Staticinterface_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
Staticlist_StaticnewvStaticoverride_the new property ID
the name of a property registered in a parent class or in an interface of this class.
The Gio.Settings class provides a convenient API for storing and retrieving application settings.
Reads and writes can be considered to be non-blocking. Reading settings with Gio.Settings is typically extremely fast: on approximately the same order of magnitude (but slower than) a GLib.HashTable lookup. Writing settings is also extremely fast in terms of time to return to your application, but can be extremely expensive for other threads and other processes. Many settings backends (including dconf) have lazy initialisation which means in the common case of the user using their computer without modifying any settings a lot of work can be avoided. For dconf, the D-Bus service doesn’t even need to be started in this case. For this reason, you should only ever modify Gio.Settings keys in response to explicit user action. Particular care should be paid to ensure that modifications are not made during startup — for example, when setting the initial value of preferences widgets. The built-in Gio.Settings.bind functionality is careful not to write settings in response to notify signals as a result of modifications that it makes to widgets.
When creating a Gio.Settings instance, you have to specify a schema that describes the keys in your settings and their types and default values, as well as some other information.
Normally, a schema has a fixed path that determines where the settings are stored in the conceptual global tree of settings. However, schemas can also be ‘relocatable’, i.e. not equipped with a fixed path. This is useful e.g. when the schema describes an ‘account’, and you want to be able to store a arbitrary number of accounts.
Paths must start with and end with a forward slash character (
/) and must not contain two sequential slash characters. Paths should be chosen based on a domain name associated with the program or library to which the settings belong. Examples of paths are/org/gtk/settings/file-chooser/and/ca/desrt/dconf-editor/. Paths should not start with/apps/,/desktop/or/system/as they often did in GConf.Unlike other configuration systems (like GConf), GSettings does not restrict keys to basic types like strings and numbers. GSettings stores values as GLib.Variant, and allows any GLib.VariantType for keys. Key names are restricted to lowercase characters, numbers and
-. Furthermore, the names must begin with a lowercase character, must not end with a-, and must not contain consecutive dashes.Similar to GConf, the default values in GSettings schemas can be localized, but the localized values are stored in gettext catalogs and looked up with the domain that is specified in the
gettext-domainattribute of the<schemalist>or<schema>elements and the category that is specified in thel10nattribute of the<default>element. The string which is translated includes all text in the<default>element, including any surrounding quotation marks.The
l10nattribute must be set tomessagesortime, and sets the locale category for translation. Themessagescategory should be used by default; usetimefor translatable date or time formats. A translation comment can be added as an XML comment immediately above the<default>element — it is recommended to add these comments to aid translators understand the meaning and implications of the default value. An optional translationcontextattribute can be set on the<default>element to disambiguate multiple defaults which use the same string.For example:
Translations of default values must remain syntactically valid serialized GLib.Variants (e.g. retaining any surrounding quotation marks) or runtime errors will occur.
GSettings uses schemas in a compact binary form that is created by the
glib-compile-schemasutility. The input is a schema description in an XML format.A DTD for the gschema XML format can be found here: gschema.dtd
The
glib-compile-schemastool expects schema files to have the extension.gschema.xml.At runtime, schemas are identified by their ID (as specified in the
idattribute of the<schema>element). The convention for schema IDs is to use a dotted name, similar in style to a D-Bus bus name, e.g.org.gnome.SessionManager. In particular, if the settings are for a specific service that owns a D-Bus bus name, the D-Bus bus name and schema ID should match. For schemas which deal with settings not associated with one named application, the ID should not use StudlyCaps, e.g.org.gnome.font-rendering.In addition to GLib.Variant types, keys can have types that have enumerated types. These can be described by a
<choice>,<enum>or<flags>element, as seen in the second example below. The underlying type of such a key is string, but you can use Gio.Settings.get_enum, Gio.Settings.set_enum, Gio.Settings.get_flags, Gio.Settings.set_flags access the numeric values corresponding to the string value of enum and flags keys.An example for default value:
An example for ranges, choices and enumerated types:
Vendor overrides
Default values are defined in the schemas that get installed by an application. Sometimes, it is necessary for a vendor or distributor to adjust these defaults. Since patching the XML source for the schema is inconvenient and error-prone,
glib-compile-schemasreads so-called ‘vendor override’ files. These are keyfiles in the same directory as the XML schema sources which can override default values. The schema ID serves as the group name in the key file, and the values are expected in serialized GLib.Variant form, as in the following example:glib-compile-schemasexpects schema files to have the extension.gschema.override.Delay-apply mode
By default, values set on a Gio.Settings instance immediately start to be written to the backend (although these writes may not complete by the time that Gio.Settings.set) returns; see Gio.Settings.sync).
In order to allow groups of settings to be changed simultaneously and atomically, GSettings also supports a ‘delay-apply’ mode. In this mode, updated values are kept locally in the Gio.Settings instance until they are explicitly applied by calling Gio.Settings.apply.
For example, this could be useful for a preferences dialog where the preferences all need to be applied simultaneously when the user clicks ‘Save’.
Switching a Gio.Settings instance to ‘delay-apply’ mode is a one-time irreversible operation: from that point onwards, all changes made to that Gio.Settings have to be explicitly applied by calling Gio.Settings.apply. The ‘delay-apply’ mode is also propagated to any child settings objects subsequently created using Gio.Settings.get_child.
At any point, the set of unapplied changes can be queried using Gio.Settings.has_unapplied, and discarded by calling Gio.Settings.revert.
Binding
A very convenient feature of GSettings lets you bind GObject.Object properties directly to settings, using Gio.Settings.bind. Once a GObject.Object property has been bound to a setting, changes on either side are automatically propagated to the other side. GSettings handles details like mapping between GObject.Object and GLib.Variant types, and preventing infinite cycles.
This makes it very easy to hook up a preferences dialog to the underlying settings. To make this even more convenient, GSettings looks for a boolean property with the name
sensitivityand automatically binds it to the writability of the bound setting. If this ‘magic’ gets in the way, it can be suppressed with theG_SETTINGS_BIND_NO_SENSITIVITYflag.Relocatable schemas
A relocatable schema is one with no
pathattribute specified on its<schema>element. By using Gio.Settings.new_with_path, a Gio.Settings object can be instantiated for a relocatable schema, assigning a path to the instance. Paths passed to Gio.Settings.new_with_path will typically be constructed dynamically from a constant prefix plus some form of instance identifier; but they must still be valid GSettings paths. Paths could also be constant and used with a globally installed schema originating from a dependency library.For example, a relocatable schema could be used to store geometry information for different windows in an application. If the schema ID was
org.foo.MyApp.Window, it could be instantiated for paths/org/foo/MyApp/main/,/org/foo/MyApp/document-1/,/org/foo/MyApp/document-2/, etc. If any of the paths are well-known they can be specified as<child>elements in the parent schema, e.g.:Build system integration
Meson
GSettings is natively supported by Meson’s GNOME module.
You can install the schemas as any other data file:
You can use
gnome.post_install()function to compile the schemas on installation:If an enumerated type defined in a C header file is to be used in a GSettings schema, it can either be defined manually using an
<enum>element in the schema XML, or it can be extracted automatically from the C header. This approach is preferred, as it ensures the two representations are always synchronised. To do so, you will need to use thegnome.mkenums()function with the following templates:It is recommended to validate your schemas as part of the test suite for your application:
If your application allows running uninstalled, you should also use the
gnome.compile_schemas()function to compile the schemas in the current build directory:Autotools
GSettings comes with autotools integration to simplify compiling and installing schemas. To add GSettings support to an application, add the following to your
configure.ac:In the appropriate
Makefile.am, use the following snippet to compile and install the named schema:If an enumerated type defined in a C header file is to be used in a GSettings schema, it can either be defined manually using an
<enum>element in the schema XML, or it can be extracted automatically from the C header. This approach is preferred, as it ensures the two representations are always synchronised. To do so, add the following to the relevantMakefile.am:gsettings_ENUM_NAMESPACEspecifies the schema namespace for the enum files, which are specified ingsettings_ENUM_FILES. This will generate aorg.foo.MyApp.enums.xmlfile containing the extracted enums, which will be automatically included in the schema compilation, install and uninstall rules. It should not be committed to version control or included inEXTRA_DIST.Localization
No changes are needed to the build system to mark a schema XML file for translation. Assuming it sets the
gettext-domainattribute, a schema may be marked for translation by adding it toPOTFILES.in, assuming gettext 0.19 or newer is in use (the preferred method for translation):Alternatively, if intltool 0.50.1 is in use:
GSettings will use gettext to look up translations for the
<summary>and<description>elements, and also any<default>elements which have al10nattribute set.Translations must not be included in the
.gschema.xmlfile by the build system, for example by using a rule to generate the XML file from a template.