## GSettings

GSettings — High-level API for application settings

## Functions

GSettings * | g_settings_new ()
GSettings * | g_settings_new_with_path ()
GSettings * | g_settings_new_with_backend ()
GSettings * | g_settings_new_with_backend_and_path ()
GSettings * | g_settings_new_full ()
void | g_settings_sync ()
GVariant * | g_settings_get_value ()
gboolean | g_settings_set_value ()
gboolean | g_settings_is_writable ()
void | g_settings_delay ()
void | g_settings_apply ()
void | g_settings_revert ()
gboolean | g_settings_get_has_unapplied ()
GSettings * | g_settings_get_child ()
void | g_settings_reset ()
GVariant * | g_settings_get_user_value ()
GVariant * | g_settings_get_default_value ()
const gchar * const * | g_settings_list_schemas ()
const gchar * const * | g_settings_list_relocatable_schemas ()
gchar ** | g_settings_list_keys ()
gchar ** | g_settings_list_children ()
GVariant * | g_settings_get_range ()
gboolean | g_settings_range_check ()
void | g_settings_get ()
gboolean | g_settings_set ()
gboolean | g_settings_get_boolean ()
gboolean | g_settings_set_boolean ()
gint | g_settings_get_int ()
gboolean | g_settings_set_int ()
gint64 | g_settings_get_int64 ()
gboolean | g_settings_set_int64 ()
guint | g_settings_get_uint ()
gboolean | g_settings_set_uint ()
guint64 | g_settings_get_uint64 ()
gboolean | g_settings_set_uint64 ()
gdouble | g_settings_get_double ()
gboolean | g_settings_set_double ()
gchar * | g_settings_get_string ()
gboolean | g_settings_set_string ()
gchar ** | g_settings_get_strv ()
gboolean | g_settings_set_strv ()
gint | g_settings_get_enum ()
gboolean | g_settings_set_enum ()
guint | g_settings_get_flags ()
gboolean | g_settings_set_flags ()
gboolean | (*GSettingsGetMapping) ()
gpointer | g_settings_get_mapped ()
void | g_settings_bind ()
void | g_settings_bind_with_mapping ()
void | g_settings_bind_writable ()
void | g_settings_unbind ()
GVariant * | (*GSettingsBindSetMapping) ()
gboolean | (*GSettingsBindGetMapping) ()
GAction * | g_settings_create_action ()

## Properties

GSettingsBackend * | backend | Read / Write / Construct Only
gboolean | delay-apply | Read
gboolean | has-unapplied | Read
gchar * | path | Read / Write / Construct Only
gchar * | schema | Read / Write / Construct Only
gchar * | schema-id | Read / Write / Construct Only
GSettingsSchema * | settings-schema | Read / Write / Construct Only

## Signals

gboolean | change-event | Run Last
void | changed | Has Details
gboolean | writable-change-event | Run Last
void | writable-changed | Has Details

## Types and Values

| GSettings
enum | GSettingsBindFlags

## Object Hierarchy

        GObject
        ╰── GSettings

## Includes

    #include <gio/gio.h>

## Description

The GSettings class provides a convenient API for storing and retrieving application settings.

Reads and writes can be considered to be non-blocking. Reading settings with GSettings is typically extremely fast: on approximately the same order of magnitude (but slower than) a GHashTable 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 GSettings 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 `g_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 GSettings 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 GVariant, and allows any GVariantType 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-domain` attribute of the <schemalist> or <schema> elements and the category that is specified in the `l10n` attribute of the <default> element. The string which is translated includes all text in the <default> element, including any surrounding quotation marks.

The `l10n` attribute must be set to `messages` or `time`, and sets the locale category for translation. The `messages` category should be used by default; use `time` for 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 translation `context` attribute can be set on the <default> element to disambiguate multiple defaults which use the same string.

For example:

    1
    2
    3
    4

    <!-- Translators: A list of words which are not allowed to be typed, in
         GVariant serialization syntax.
         See: https://developer.gnome.org/glib/stable/gvariant-text.html -->
    <default l10n='messages' context='Banned words'>['bad', 'words']</default>

Translations of default values must remain syntactically valid serialized GVariants (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-schemas utility. 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-schemas tool expects schema files to have the extension `.gschema.xml`.

At runtime, schemas are identified by their id (as specified in the id attribute 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 GVariant types, keys can have types that have enumerated types. These can be described by a <choice>, <enum> or <flags> element, as seen in the example. The underlying type of such a key is string, but you can use `g_settings_get_enum()`, `g_settings_set_enum()`, `g_settings_get_flags()`, `g_settings_set_flags()` access the numeric values corresponding to the string value of enum and flags keys.

An example for default value:

    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17

    <schemalist>
      <schema id="org.gtk.Test" path="/org/gtk/Test/" gettext-domain="test">

        <key name="greeting" type="s">
          <default l10n="messages">"Hello, earthlings"</default>
          <summary>A greeting</summary>
          <description>
            Greeting of the invading martians
          </description>
        </key>

        <key name="box" type="(ii)">
          <default>(20,30)</default>
        </key>

      </schema>
    </schemalist>

An example for ranges, choices and enumerated types:

    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42

    <schemalist>

      <enum id="org.gtk.Test.myenum">
        <value nick="first" value="1"/>
        <value nick="second" value="2"/>
      </enum>

      <flags id="org.gtk.Test.myflags">
        <value nick="flag1" value="1"/>
        <value nick="flag2" value="2"/>
        <value nick="flag3" value="4"/>
      </flags>

      <schema id="org.gtk.Test">

        <key name="key-with-range" type="i">
          <range min="1" max="100"/>
          <default>10</default>
        </key>

        <key name="key-with-choices" type="s">
          <choices>
            <choice value='Elisabeth'/>
            <choice value='Annabeth'/>
            <choice value='Joe'/>
          </choices>
          <aliases>
            <alias value='Anna' target='Annabeth'/>
            <alias value='Beth' target='Elisabeth'/>
          </aliases>
          <default>'Joe'</default>
        </key>

        <key name='enumerated-key' enum='org.gtk.Test.myenum'>
          <default>'first'</default>
        </key>

        <key name='flags-key' flags='org.gtk.Test.myflags'>
          <default>["flag1","flag2"]</default>
        </key>
      </schema>
    </schemalist>

#### 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-schemas reads 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 GVariant form, as in the following example:

    1
    2
    3

    [org.gtk.Example]
    key1='string'
    key2=1.5

glib-compile-schemas expects schema files to have the extension `.gschema.override`.

#### Binding

A very convenient feature of GSettings lets you bind GObject properties directly to settings, using `g_settings_bind()`. Once a GObject 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 and GVariant 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 "sensitivity" and automatically binds it to the writability of the bound setting. If this 'magic' gets in the way, it can be suppressed with the G_SETTINGS_BIND_NO_SENSITIVITY flag.

#### Relocatable schemas

A relocatable schema is one with no `path` attribute specified on its <schema> element. By using `g_settings_new_with_path()`, a GSettings object can be instantiated for a relocatable schema, assigning a path to the instance. Paths passed to `g_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.:

    1
    2
    3

    <schema id="org.foo.MyApp" path="/org/foo/MyApp/">
      <child name="main" schema="org.foo.MyApp.Window"/>
    </schema>

#### Build system integration

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`:

    1

    GLIB_GSETTINGS

In the appropriate `Makefile.am`, use the following snippet to compile and install the named schema:

    1
    2
    3
    4

    gsettings_SCHEMAS = org.foo.MyApp.gschema.xml
    EXTRA_DIST = $(gsettings_SCHEMAS)

    @GSETTINGS_RULES@

No changes are needed to the build system to mark a schema XML file for translation. Assuming it sets the `gettext-domain` attribute, a schema may be marked for translation by adding it to `POTFILES.in`, assuming gettext 0.19 is in use (the preferred method for translation):

    1

    data/org.foo.MyApp.gschema.xml

Alternatively, if intltool 0.50.1 is in use:

    1

    [type: gettext/gsettings]data/org.foo.MyApp.gschema.xml

GSettings will use gettext to look up translations for the <summary> and <description> elements, and also any <default> elements which have a `l10n` attribute set. Translations must not be included in the `.gschema.xml` file by the build system, for example by using intltool XML rules with a `.gschema.xml.in` template.

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 relevant `Makefile.am`:

    1
    2

    gsettings_ENUM_NAMESPACE = org.foo.MyApp
    gsettings_ENUM_FILES = my-app-enums.h my-app-misc.h

`gsettings_ENUM_NAMESPACE` specifies the schema namespace for the enum files, which are specified in `gsettings_ENUM_FILES`. This will generate a `org.foo.MyApp.enums.xml` file 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 in `EXTRA_DIST`.

## Functions

### g_settings_new ()

    GSettings *
    g_settings_new (const gchar *schema_id);

Creates a new GSettings object with the schema specified by `schema_id` .

Signals on the newly created GSettings object will be dispatched via the thread-default GMainContext in effect at the time of the call to `g_settings_new()`. The new GSettings will hold a reference on the context. See `g_main_context_push_thread_default()`.

#### Parameters

schema_id | the id of the schema |

#### Returns

a new GSettings object

Since: 2.26

### g_settings_new_with_path ()

    GSettings *
    g_settings_new_with_path (const gchar *schema_id,
                              const gchar *path);

Creates a new GSettings object with the relocatable schema specified by `schema_id` and a given path.

You only need to do this if you want to directly create a settings object with a schema that doesn't have a specified path of its own. That's quite rare.

It is a programmer error to call this function for a schema that has an explicitly specified path.

It is a programmer error if `path` is not a valid path. A valid path begins and ends with '/' and does not contain two consecutive '/' characters.

#### Parameters

schema_id | the id of the schema |
path | the path to use |

#### Returns

a new GSettings object

Since: 2.26

### g_settings_new_with_backend ()

    GSettings *
    g_settings_new_with_backend (const gchar *schema_id,
                                 GSettingsBackend *backend);

Creates a new GSettings object with the schema specified by `schema_id` and a given GSettingsBackend.

Creating a GSettings object with a different backend allows accessing settings from a database other than the usual one. For example, it may make sense to pass a backend corresponding to the "defaults" settings database on the system to get a settings object that modifies the system default settings instead of the settings for this user.

#### Parameters

schema_id | the id of the schema |
backend | the GSettingsBackend to use |

#### Returns

a new GSettings object

Since: 2.26

### g_settings_new_with_backend_and_path ()

    GSettings *
    g_settings_new_with_backend_and_path (const gchar *schema_id,
                                          GSettingsBackend *backend,
                                          const gchar *path);

Creates a new GSettings object with the schema specified by `schema_id` and a given GSettingsBackend and path.

This is a mix of `g_settings_new_with_backend()` and `g_settings_new_with_path()`.

#### Parameters

schema_id | the id of the schema |
backend | the GSettingsBackend to use |
path | the path to use |

#### Returns

a new GSettings object

Since: 2.26

### g_settings_new_full ()

    GSettings *
    g_settings_new_full (GSettingsSchema *schema,
                         GSettingsBackend *backend,
                         const gchar *path);

Creates a new GSettings object with a given schema, backend and path.

It should be extremely rare that you ever want to use this function. It is made available for advanced use-cases (such as plugin systems that want to provide access to schemas loaded from custom locations, etc).

At the most basic level, a GSettings object is a pure composition of 4 things: a GSettingsSchema, a GSettingsBackend, a path within that backend, and a GMainContext to which signals are dispatched.

This constructor therefore gives you full control over constructing GSettings instances. The first 3 parameters are given directly as `schema` , `backend` and `path` , and the main context is taken from the thread-default (as per `g_settings_new()`).

If `backend` is `NULL` then the default backend is used.

If `path` is `NULL` then the path from the schema is used. It is an error if `path` is `NULL` and the schema has no path of its own or if `path` is non-`NULL` and not equal to the path that the schema does have.

#### Parameters

schema | a GSettingsSchema |
backend | a GSettingsBackend. | [nullable]
path | the path to use. | [nullable]

#### Returns

a new GSettings object

Since: 2.32

### g_settings_sync ()

    void
    g_settings_sync (void);

Ensures that all pending operations are complete for the default backend.

Writes made to a GSettings are handled asynchronously. For this reason, it is very unlikely that the changes have it to disk by the time `g_settings_set()` returns.

This call will block until all of the writes have made it to the backend. Since the mainloop is not running, no change notifications will be dispatched during this call (but some may be queued by the time the call is done).

### g_settings_get_value ()

    GVariant *
    g_settings_get_value (GSettings *settings,
                          const gchar *key);

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` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

a new GVariant

Since: 2.26

### g_settings_set_value ()

    gboolean
    g_settings_set_value (GSettings *settings,
                          const gchar *key,
                          GVariant *value);

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.

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | a GVariant of the correct type |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.26

### g_settings_is_writable ()

    gboolean
    g_settings_is_writable (GSettings *settings,
                            const gchar *name);

Finds out if a key can be written or not

#### Parameters

settings | a GSettings object |
name | the name of a key |

#### Returns

`TRUE` if the key `name` is writable

Since: 2.26

### g_settings_delay ()

    void
    g_settings_delay (GSettings *settings);

Changes the GSettings object into 'delay-apply' mode. In this mode, changes to `settings` are not immediately propagated to the backend, but kept locally until `g_settings_apply()` is called.

#### Parameters

settings | a GSettings object |

Since: 2.26

### g_settings_apply ()

    void
    g_settings_apply (GSettings *settings);

Applies any changes that have been made to the settings. This function does nothing unless `settings` is in 'delay-apply' mode; see `g_settings_delay()`. In the normal case settings are always applied immediately.

#### Parameters

settings | a GSettings instance |

### g_settings_revert ()

    void
    g_settings_revert (GSettings *settings);

Reverts all non-applied changes to the settings. This function does nothing unless `settings` is in 'delay-apply' mode; see `g_settings_delay()`. In the normal case settings are always applied immediately.

Change notifications will be emitted for affected keys.

#### Parameters

settings | a GSettings instance |

### g_settings_get_has_unapplied ()

    gboolean
    g_settings_get_has_unapplied (GSettings *settings);

Returns whether the GSettings object has any unapplied changes. This can only be the case if it is in 'delayed-apply' mode.

#### Parameters

settings | a GSettings object |

#### Returns

`TRUE` if `settings` has unapplied changes

Since: 2.26

### g_settings_get_child ()

    GSettings *
    g_settings_get_child (GSettings *settings,
                          const gchar *name);

Creates a child settings object which has a base path of `base-path/@name`, where `base-path` is the base path of `settings` .

The schema for the child settings object must have been declared in the schema of `settings` using a <child> element.

#### Parameters

settings | a GSettings object |
name | the name of the child schema |

#### Returns

a 'child' settings object.

[transfer full]

Since: 2.26

### g_settings_reset ()

    void
    g_settings_reset (GSettings *settings,
                      const gchar *key);

Resets `key` to its default value.

This call resets the key, as much as possible, to its default value. That might the value specified in the schema or the one set by the administrator.

#### Parameters

settings | a GSettings object |
key | the name of a key |

### g_settings_get_user_value ()

    GVariant *
    g_settings_get_user_value (GSettings *settings,
                               const gchar *key);

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 `g_settings_reset()` this function should always return `NULL` (assuming something is not wrong with the system configuration).

It is possible that `g_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` .

#### Parameters

settings | a GSettings object |
key | the key to get the user value for |

#### Returns

the user's value, if set.

[nullable][transfer full]

Since: 2.40

### g_settings_get_default_value ()

    GVariant *
    g_settings_get_default_value (GSettings *settings,
                                  const gchar *key);

Gets the "default value" of a key.

This is the value that would be read if `g_settings_reset()` were to be called on the key.

Note that this may be a different value than returned by `g_settings_schema_key_get_default_value()` if the system administrator has provided a default value.

Comparing the return values of `g_settings_get_default_value()` and `g_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` .

#### Parameters

settings | a GSettings object |
key | the key to get the default value for |

#### Returns

the default value.

[nullable][transfer full]

Since: 2.40

### g_settings_list_schemas ()

    const gchar * const *
    g_settings_list_schemas (void);

`g_settings_list_schemas` has been deprecated since version 2.40 and should not be used in newly-written code.

Use `g_settings_schema_source_list_schemas()` instead. If you used `g_settings_list_schemas()` to check for the presence of a particular schema, use `g_settings_schema_source_lookup()` instead of your whole loop.

Deprecated.

#### Returns

a list of GSettings schemas that are available. The list must not be modified or freed.

[element-type utf8][transfer none]

Since: 2.26

### g_settings_list_relocatable_schemas ()

    const gchar * const *
    g_settings_list_relocatable_schemas (void);

`g_settings_list_relocatable_schemas` has been deprecated since version 2.40 and should not be used in newly-written code.

Use `g_settings_schema_source_list_schemas()` instead

Deprecated.

#### Returns

a list of relocatable GSettings schemas that are available. The list must not be modified or freed.

[element-type utf8][transfer none]

Since: 2.28

### g_settings_list_keys ()

    gchar **
    g_settings_list_keys (GSettings *settings);

`g_settings_list_keys` is deprecated and should not be used in newly-written code.

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 `g_strfreev()` when you are done with it.

#### Parameters

settings | a GSettings object |

#### Returns

a list of the keys on `settings` .

[transfer full][element-type utf8]

### g_settings_list_children ()

    gchar **
    g_settings_list_children (GSettings *settings);

Gets the list of children on `settings` .

The list is exactly the list of strings for which it is not an error to call `g_settings_get_child()`.

For GSettings objects that are lists, this value can change at any time and you should connect to the "children-changed" signal to watch for those changes. Note that there is a race condition here: you may request a child after listing it only for it to have been destroyed in the meantime. For this reason, `g_settings_get_child()` may return `NULL` even for a child that was listed by this function.

For GSettings objects that are not lists, you should probably not be calling 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 `g_strfreev()` when you are done with it.

#### Parameters

settings | a GSettings object |

#### Returns

a list of the children on `settings` .

[transfer full][element-type utf8]

### g_settings_get_range ()

    GVariant *
    g_settings_get_range (GSettings *settings,
                          const gchar *key);

`g_settings_get_range` has been deprecated since version 2.40 and should not be used in newly-written code.

Use `g_settings_schema_key_get_range()` instead.

Queries the range of a key.

#### Parameters

settings | a GSettings |
key | the key to query the range of |

Since: 2.28

### g_settings_range_check ()

    gboolean
    g_settings_range_check (GSettings *settings,
                            const gchar *key,
                            GVariant *value);

`g_settings_range_check` has been deprecated since version 2.40 and should not be used in newly-written code.

Use `g_settings_schema_key_range_check()` instead.

Checks if the given `value` is of the correct type and within the permitted range for `key` .

#### Parameters

settings | a GSettings |
key | the key to check |
value | the value to check |

#### Returns

`TRUE` if `value` is valid for `key`

Since: 2.28

### g_settings_get ()

    void
    g_settings_get (GSettings *settings,
                    const gchar *key,
                    const gchar *format,
                    ...);

Gets the value that is stored at `key` in `settings` .

A convenience function that combines `g_settings_get_value()` with `g_variant_get()`.

It is a programmer error to give a `key` that isn't contained in the schema for `settings` or for the GVariantType of `format` to mismatch the type given in the schema.

#### Parameters

settings | a GSettings object |
key | the key to get the value for |
format | a GVariant format string |
... | arguments as per `format` |

Since: 2.26

### g_settings_set ()

    gboolean
    g_settings_set (GSettings *settings,
                    const gchar *key,
                    const gchar *format,
                    ...);

Sets `key` in `settings` to `value` .

A convenience function that combines `g_settings_set_value()` with `g_variant_new()`.

It is a programmer error to give a `key` that isn't contained in the schema for `settings` or for the GVariantType of `format` to mismatch the type given in the schema.

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
format | a GVariant format string |
... | arguments as per `format` |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.26

### g_settings_get_boolean ()

    gboolean
    g_settings_get_boolean (GSettings *settings,
                            const gchar *key);

Gets the value that is stored at `key` in `settings` .

A convenience variant of `g_settings_get()` for booleans.

It is a programmer error to give a `key` that isn't specified as having a boolean type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

a boolean

Since: 2.26

### g_settings_set_boolean ()

    gboolean
    g_settings_set_boolean (GSettings *settings,
                            const gchar *key,
                            gboolean value);

Sets `key` in `settings` to `value` .

A convenience variant of `g_settings_set()` for booleans.

It is a programmer error to give a `key` that isn't specified as having a boolean type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | the value to set it to |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.26

### g_settings_get_int ()

    gint
    g_settings_get_int (GSettings *settings,
                        const gchar *key);

Gets the value that is stored at `key` in `settings` .

A convenience variant of `g_settings_get()` for 32-bit integers.

It is a programmer error to give a `key` that isn't specified as having a int32 type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

an integer

Since: 2.26

### g_settings_set_int ()

    gboolean
    g_settings_set_int (GSettings *settings,
                        const gchar *key,
                        gint value);

Sets `key` in `settings` to `value` .

A convenience variant of `g_settings_set()` for 32-bit integers.

It is a programmer error to give a `key` that isn't specified as having a int32 type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | the value to set it to |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.26

### g_settings_get_int64 ()

    gint64
    g_settings_get_int64 (GSettings *settings,
                          const gchar *key);

Gets the value that is stored at `key` in `settings` .

A convenience variant of `g_settings_get()` for 64-bit integers.

It is a programmer error to give a `key` that isn't specified as having a int64 type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

a 64-bit integer

Since: 2.50

### g_settings_set_int64 ()

    gboolean
    g_settings_set_int64 (GSettings *settings,
                          const gchar *key,
                          gint64 value);

Sets `key` in `settings` to `value` .

A convenience variant of `g_settings_set()` for 64-bit integers.

It is a programmer error to give a `key` that isn't specified as having a int64 type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | the value to set it to |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.50

### g_settings_get_uint ()

    guint
    g_settings_get_uint (GSettings *settings,
                         const gchar *key);

Gets the value that is stored at `key` in `settings` .

A convenience variant of `g_settings_get()` for 32-bit unsigned integers.

It is a programmer error to give a `key` that isn't specified as having a uint32 type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

an unsigned integer

Since: 2.30

### g_settings_set_uint ()

    gboolean
    g_settings_set_uint (GSettings *settings,
                         const gchar *key,
                         guint value);

Sets `key` in `settings` to `value` .

A convenience variant of `g_settings_set()` for 32-bit unsigned integers.

It is a programmer error to give a `key` that isn't specified as having a uint32 type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | the value to set it to |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.30

### g_settings_get_uint64 ()

    guint64
    g_settings_get_uint64 (GSettings *settings,
                           const gchar *key);

Gets the value that is stored at `key` in `settings` .

A convenience variant of `g_settings_get()` for 64-bit unsigned integers.

It is a programmer error to give a `key` that isn't specified as having a uint64 type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

a 64-bit unsigned integer

Since: 2.50

### g_settings_set_uint64 ()

    gboolean
    g_settings_set_uint64 (GSettings *settings,
                           const gchar *key,
                           guint64 value);

Sets `key` in `settings` to `value` .

A convenience variant of `g_settings_set()` for 64-bit unsigned integers.

It is a programmer error to give a `key` that isn't specified as having a uint64 type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | the value to set it to |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.50

### g_settings_get_double ()

    gdouble
    g_settings_get_double (GSettings *settings,
                           const gchar *key);

Gets the value that is stored at `key` in `settings` .

A convenience variant of `g_settings_get()` for doubles.

It is a programmer error to give a `key` that isn't specified as having a 'double' type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

a double

Since: 2.26

### g_settings_set_double ()

    gboolean
    g_settings_set_double (GSettings *settings,
                           const gchar *key,
                           gdouble value);

Sets `key` in `settings` to `value` .

A convenience variant of `g_settings_set()` for doubles.

It is a programmer error to give a `key` that isn't specified as having a 'double' type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | the value to set it to |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.26

### g_settings_get_string ()

    gchar *
    g_settings_get_string (GSettings *settings,
                           const gchar *key);

Gets the value that is stored at `key` in `settings` .

A convenience variant of `g_settings_get()` for strings.

It is a programmer error to give a `key` that isn't specified as having a string type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

a newly-allocated string

Since: 2.26

### g_settings_set_string ()

    gboolean
    g_settings_set_string (GSettings *settings,
                           const gchar *key,
                           const gchar *value);

Sets `key` in `settings` to `value` .

A convenience variant of `g_settings_set()` for strings.

It is a programmer error to give a `key` that isn't specified as having a string type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | the value to set it to |

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.26

### g_settings_get_strv ()

    gchar **
    g_settings_get_strv (GSettings *settings,
                         const gchar *key);

A convenience variant of `g_settings_get()` for string arrays.

It is a programmer error to give a `key` that isn't specified as having an array of strings type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

a newly-allocated, `NULL`-terminated array of strings, the value that is stored at `key` in `settings` .

[array zero-terminated=1][transfer full]

Since: 2.26

### g_settings_set_strv ()

    gboolean
    g_settings_set_strv (GSettings *settings,
                         const gchar *key,
                         const gchar *const *value);

Sets `key` in `settings` to `value` .

A convenience variant of `g_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 array of strings type in the schema for `settings` .

#### Parameters

settings | a GSettings object |
key | the name of the key to set |
value | the value to set it to, or `NULL`. | [nullable][array zero-terminated=1]

#### Returns

`TRUE` if setting the key succeeded, `FALSE` if the key was not writable

Since: 2.26

### g_settings_get_enum ()

    gint
    g_settings_get_enum (GSettings *settings,
                         const gchar *key);

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.

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

the enum value

Since: 2.26

### g_settings_set_enum ()

    gboolean
    g_settings_set_enum (GSettings *settings,
                         const gchar *key,
                         gint value);

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 `g_settings_get_string()` will return the 'nick' associated with `value` .

#### Parameters

settings | a GSettings object |
key | a key, within `settings` |
value | an enumerated value |

#### Returns

`TRUE`, if the set succeeds

### g_settings_get_flags ()

    guint
    g_settings_get_flags (GSettings *settings,
                          const gchar *key);

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 an 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.

#### Parameters

settings | a GSettings object |
key | the key to get the value for |

#### Returns

the flags value

Since: 2.26

### g_settings_set_flags ()

    gboolean
    g_settings_set_flags (GSettings *settings,
                          const gchar *key,
                          guint value);

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 `g_settings_get_strv()` will return an array of 'nicks'; one for each bit in `value` .

#### Parameters

settings | a GSettings object |
key | a key, within `settings` |
value | a flags value |

#### Returns

`TRUE`, if the set succeeds

### GSettingsGetMapping ()

    gboolean
    (*GSettingsGetMapping) (GVariant *value,
                            gpointer *result,
                            gpointer user_data);

The type of the function that is used to convert from a value stored in a GSettings to a value that is useful to the application.

If the value is successfully mapped, the result should be stored at `result` and `TRUE` returned. If mapping fails (for example, if `value` is not in the right format) then `FALSE` should be returned.

If `value` is `NULL` then it means that the mapping function is being given a "last chance" to successfully return a valid value. `TRUE` must be returned in this case.

#### Parameters

value | the GVariant to map, or `NULL` |
result | the result of the mapping. | [out]
user_data | the user data that was passed to `g_settings_get_mapped()`. | [closure]

#### Returns

`TRUE` if the conversion succeeded, `FALSE` in case of an error

### g_settings_get_mapped ()

    gpointer
    g_settings_get_mapped (GSettings *settings,
                           const gchar *key,
                           GSettingsGetMapping mapping,
                           gpointer user_data);

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.

#### Parameters

settings | a GSettings object |
key | the key to get the value for |
mapping | the function to map the value in the settings database to the value used by the application. | [scope call]
user_data | user data for `mapping` |

#### Returns

the result, which may be `NULL`.

[transfer full]

### g_settings_bind ()

    void
    g_settings_bind (GSettings *settings,
                     const gchar *key,
                     gpointer object,
                     const gchar *property,
                     GSettingsBindFlags flags);

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 `g_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 `G_SETTINGS_BIND_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 `g_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.

#### Parameters

settings | a GSettings object |
key | the key to bind |
object | a GObject. | [type GObject.Object]
property | the name of the property to bind |
flags | flags for the binding |

Since: 2.26

### g_settings_bind_with_mapping ()

    void
    g_settings_bind_with_mapping (GSettings *settings,
                                  const gchar *key,
                                  gpointer object,
                                  const gchar *property,
                                  GSettingsBindFlags flags,
                                  GSettingsBindGetMapping get_mapping,
                                  GSettingsBindSetMapping set_mapping,
                                  gpointer user_data,
                                  GDestroyNotify destroy);

Create a binding between the `key` in the `settings` object and the property `property` of `object` .

The binding uses the provided mapping functions to map between settings and property values.

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.

[skip]

#### Parameters

settings | a GSettings object |
key | the key to bind |
object | a GObject. | [type GObject.Object]
property | the name of the property to bind |
flags | flags for the binding |
get_mapping | a function that gets called to convert values from `settings` to `object` , or `NULL` to use the default GIO mapping |
set_mapping | a function that gets called to convert values from `object` to `settings` , or `NULL` to use the default GIO mapping |
user_data | data that gets passed to `get_mapping` and `set_mapping` |
destroy | GDestroyNotify function for `user_data` |

Since: 2.26

### g_settings_bind_writable ()

    void
    g_settings_bind_writable (GSettings *settings,
                              const gchar *key,
                              gpointer object,
                              const gchar *property,
                              gboolean inverted);

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.

#### Parameters

settings | a GSettings object |
key | the key to bind |
object | a GObject. | [type GObject.Object]
property | the name of a boolean property to bind |
inverted | whether to 'invert' the value |

Since: 2.26

### g_settings_unbind ()

    void
    g_settings_unbind (gpointer object,
                       const gchar *property);

Removes 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.

#### Parameters

object | the object. | [type GObject.Object]
property | the property whose binding is removed |

Since: 2.26

### GSettingsBindSetMapping ()

    GVariant *
    (*GSettingsBindSetMapping) (const GValue *value,
                                const GVariantType *expected_type,
                                gpointer user_data);

The type for the function that is used to convert an object property value to a GVariant for storing it in GSettings.

#### Parameters

value | a GValue containing the property value to map |
expected_type | the GVariantType to create |
user_data | user data that was specified when the binding was created |

#### Returns

a new GVariant holding the data from `value` , or `NULL` in case of an error

### GSettingsBindGetMapping ()

    gboolean
    (*GSettingsBindGetMapping) (GValue *value,
                                GVariant *variant,
                                gpointer user_data);

The type for the function that is used to convert from GSettings to an object property. The `value` is already initialized to hold values of the appropriate type.

#### Parameters

value | return location for the property value |
variant | the GVariant |
user_data | user data that was specified when the binding was created |

#### Returns

`TRUE` if the conversion succeeded, `FALSE` in case of an error

### g_settings_create_action ()

    GAction *
    g_settings_create_action (GSettings *settings,
                              const gchar *key);

Creates a GAction corresponding to a given GSettings 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).

#### Parameters

settings | a GSettings |
key | the name of a key in `settings` |

#### Returns

a new GAction.

[transfer full]

Since: 2.32

## Types and Values

### GSettings

    typedef struct _GSettings GSettings;

GSettings is an opaque data structure and can only be accessed using the following functions.

### enum GSettingsBindFlags

Flags used when creating a binding. These flags determine in which direction the binding works. The default is to synchronize in both directions.

#### Members

G_SETTINGS_BIND_DEFAULT | Equivalent to `G_SETTINGS_BIND_GET|G_SETTINGS_BIND_SET` |
G_SETTINGS_BIND_GET | Update the GObject property when the setting changes. It is an error to use this flag if the property is not writable. |
G_SETTINGS_BIND_SET | Update the setting when the GObject property changes. It is an error to use this flag if the property is not readable. |
G_SETTINGS_BIND_NO_SENSITIVITY | Do not try to bind a "sensitivity" property to the writability of the setting |
G_SETTINGS_BIND_GET_NO_CHANGES | When set in addition to G_SETTINGS_BIND_GET, set the GObject property value initially from the setting, but do not listen for changes of the setting |
G_SETTINGS_BIND_INVERT_BOOLEAN | When passed to `g_settings_bind()`, uses a pair of mapping functions that invert the boolean value when mapping between the setting and the property. The setting and property must both be booleans. You cannot pass this flag to `g_settings_bind_with_mapping()`. |

## Property Details

### The `“backend”` property

      “backend”                  GSettingsBackend *

The name of the context that the settings are stored in.

Flags: Read / Write / Construct Only

### The `“delay-apply”` property

      “delay-apply”              gboolean

Whether the GSettings object is in 'delay-apply' mode. See `g_settings_delay()` for details.

Flags: Read

Default value: FALSE

Since: 2.28

### The `“has-unapplied”` property

      “has-unapplied”            gboolean

If this property is `TRUE`, the GSettings object has outstanding changes that will be applied when `g_settings_apply()` is called.

Flags: Read

Default value: FALSE

### The `“path”` property

      “path”                     gchar *

The path within the backend where the settings are stored.

Flags: Read / Write / Construct Only

Default value: NULL

### The `“schema”` property

      “schema”                   gchar *

The name of the schema that describes the types of keys for this GSettings object.

The type of this property is *not* GSettingsSchema. GSettingsSchema 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 'settings-schema' property if you wish to pass in a GSettingsSchema.

`GSettings:schema` has been deprecated since version 2.32 and should not be used in newly-written code.

Use the 'schema-id' property instead. In a future version, this property may instead refer to a GSettingsSchema.

Flags: Read / Write / Construct Only

Default value: NULL

### The `“schema-id”` property

      “schema-id”                gchar *

The name of the schema that describes the types of keys for this GSettings object.

Flags: Read / Write / Construct Only

Default value: NULL

### The `“settings-schema”` property

      “settings-schema”          GSettingsSchema *

The GSettingsSchema describing the types of keys for this GSettings object.

Ideally, this property would be called 'schema'. GSettingsSchema has only existed since version 2.32, however, and before then the 'schema' property was used to refer to the ID of the schema rather than the schema itself. Take care.

Flags: Read / Write / Construct Only

## Signal Details

### The `“change-event”` signal

    gboolean
    user_function (GSettings *settings,
                   gpointer   keys,
                   gint       n_keys,
                   gpointer   user_data)

The "change-event" signal is emitted once per change event that affects this settings object. You should connect to this signal only if you are interested in viewing groups of changes before they are split out into multiple emissions of the "changed" signal. For most use cases it is more appropriate to use the "changed" signal.

In the event that the change event applies to one or more specified keys, `keys` will be an array of GQuark of length `n_keys` . In the event that the change event applies to the GSettings object as a whole (ie: potentially every key has been changed) then `keys` will be `NULL` and `n_keys` will be 0.

The default handler for this signal invokes the "changed" signal for each affected key. If any other connected handler returns `TRUE` then this default functionality will be suppressed.

#### Parameters

settings | the object on which the signal was emitted |
keys | an array of GQuarks for the changed keys, or `NULL`. | [array length=n_keys][element-type GQuark][nullable]
n_keys | the length of the `keys` array, or 0 |
user_data | user data set when the signal handler was connected. |

#### Returns

`TRUE` to stop other handlers from being invoked for the event. FALSE to propagate the event further.

Flags: Run Last

### The `“changed”` signal

    void
    user_function (GSettings *settings,
                   gchar     *key,
                   gpointer   user_data)

The "changed" signal is emitted when a key has potentially changed. You should call one of the `g_settings_get()` calls to check the new value.

This signal supports detailed connections. You can connect to the detailed signal "changed::x" in order to only receive callbacks when key "x" changes.

Note that `settings` only emits this signal if you have read `key` at least once while a signal handler was already connected for `key` .

#### Parameters

settings | the object on which the signal was emitted |
key | the name of the key that changed |
user_data | user data set when the signal handler was connected. |

Flags: Has Details

### The `“writable-change-event”` signal

    gboolean
    user_function (GSettings *settings,
                   guint      key,
                   gpointer   user_data)

The "writable-change-event" signal is emitted once per writability change event that affects this settings object. You should connect to this signal if you are interested in viewing groups of changes before they are split out into multiple emissions of the "writable-changed" signal. For most use cases it is more appropriate to use the "writable-changed" signal.

In the event that the writability change applies only to a single key, `key` will be set to the GQuark for that key. In the event that the writability change affects the entire settings object, `key` will be 0.

The default handler for this signal invokes the "writable-changed" and "changed" signals for each affected key. This is done because changes in writability might also imply changes in value (if for example, a new mandatory setting is introduced). If any other connected handler returns `TRUE` then this default functionality will be suppressed.

#### Parameters

settings | the object on which the signal was emitted |
key | the quark of the key, or 0 |
user_data | user data set when the signal handler was connected. |

#### Returns

`TRUE` to stop other handlers from being invoked for the event. FALSE to propagate the event further.

Flags: Run Last

### The `“writable-changed”` signal

    void
    user_function (GSettings *settings,
                   gchar     *key,
                   gpointer   user_data)

The "writable-changed" signal is emitted when the writability of a key has potentially changed. You should call `g_settings_is_writable()` in order to determine the new status.

This signal supports detailed connections. You can connect to the detailed signal "writable-changed::x" in order to only receive callbacks when the writability of "x" changes.

#### Parameters

settings | the object on which the signal was emitted |
key | the key |
user_data | user data set when the signal handler was connected. |

Flags: Has Details