GObject.ParamSpec¶

Methods¶

class	`is_valid_name` (name)
	`get_blurb` ()
	`get_default_value` ()
	`get_name` ()
	`get_name_quark` ()
	`get_nick` ()
	`get_qdata` (quark)
	`get_redirect_target` ()
	`set_qdata` (quark, data)
	`sink` ()
	`steal_qdata` (quark)

Virtual Methods¶

	`do_finalize` ()
	`do_value_is_valid` (value)
	`do_value_set_default` (value)
	`do_value_validate` (value)
	`do_values_cmp` (value1, value2)

Fields¶

Name	Type	Access	Description
flags	`GObject.ParamFlags`	r	`GObject.ParamFlags` flags for this parameter
g_type_instance	`GObject.TypeInstance`	r	private `GObject.TypeInstance` portion
name	`str`	r	name of this parameter: always an interned string
owner_type	`GObject.GType`	r	`GObject.GType` type that uses (introduces) this parameter
param_id	`int`	r
qdata	`GLib.Data`	r
ref_count	`int`	r
value_type	`GObject.GType`	r	the `GObject.Value` type for this parameter

Class Details¶

class GObject.ParamSpec¶

Abstract:: Yes
Structure:: GObject.ParamSpecClass

GObject.ParamSpec is an object structure that encapsulates the metadata required to specify parameters, such as e.g. GObject.Object properties.

Parameter names

A property name consists of one or more segments consisting of ASCII letters and digits, separated by either the - or _ character. The first character of a property name must be a letter. These are the same rules as for signal naming (see GObject.signal_new()).

When creating and looking up a GObject.ParamSpec, either separator can be used, but they cannot be mixed. Using - is considerably more efficient, and is the ‘canonical form’. Using _ is discouraged.

classmethod is_valid_name(name)¶

Parameters:: name (str) – the canonical name of the property
Returns:: True if name is a valid property name, False otherwise.
Return type:: bool

Validate a property name for a GObject.ParamSpec. This can be useful for dynamically-generated properties which need to be validated at run-time before actually trying to create them.

See canonical parameter names for details of the rules for valid names.

New in version 2.66.

get_blurb()¶

Returns:: the short description of self.
Return type:: str or None

Get the short description of a GObject.ParamSpec.

get_default_value()¶

Returns:: a pointer to a GObject.Value which must not be modified
Return type:: GObject.Value

Gets the default value of self as a pointer to a GObject.Value.

The GObject.Value will remain valid for the life of self.

New in version 2.38.

get_name()¶

Returns:: the name of self.
Return type:: str

Get the name of a GObject.ParamSpec.

The name is always an “interned” string (as per GLib.intern_string()). This allows for pointer-value comparisons.

get_name_quark()¶

Returns:: the GQuark for self->name.
Return type:: int

Gets the GQuark for the name.

New in version 2.46.

get_nick()¶

Returns:: the nickname of self.
Return type:: str

Get the nickname of a GObject.ParamSpec.

get_qdata(quark)¶

Parameters:: quark (int) – a #GQuark, naming the user data pointer
Returns:: the user data pointer set, or None
Return type:: object or None

Gets back user data pointers stored via GObject.ParamSpec.set_qdata().

get_redirect_target()¶

Returns:: paramspec to which requests on this paramspec should be redirected, or None if none.
Return type:: GObject.ParamSpec or None

If the paramspec redirects operations to another paramspec, returns that paramspec. Redirect is used typically for providing a new implementation of a property in a derived type while preserving all the properties from the parent type. Redirection is established by creating a property of type GObject.ParamSpecOverride. See GObject.ObjectClass.override_property() for an example of the use of this capability.

New in version 2.4.

set_qdata(quark, data)¶

Parameters:

quark (int) – a #GQuark, naming the user data pointer
data (object or None) – an opaque user data pointer

Sets an opaque, named pointer on a GObject.ParamSpec. The name is specified through a #GQuark (retrieved e.g. via GLib.quark_from_static_string()), and the pointer can be gotten back from the self with GObject.ParamSpec.get_qdata(). Setting a previously set user data pointer, overrides (frees) the old pointer set, using None as pointer essentially removes the data stored.

sink()¶: The initial reference count of a newly created GObject.ParamSpec is 1, even though no one has explicitly called g_param_spec_ref() on it yet. So the initial reference count is flagged as “floating”, until someone calls g_param_spec_ref (pspec); g_param_spec_sink (pspec); in sequence on it, taking over the initial reference count (thus ending up with a self that has a reference count of 1 still, but is not flagged “floating” anymore).

steal_qdata(quark)¶

Parameters:: quark (int) – a #GQuark, naming the user data pointer
Returns:: the user data pointer set, or None
Return type:: object or None

Gets back user data pointers stored via GObject.ParamSpec.set_qdata() and removes the data from self 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.

do_finalize() virtual¶

do_value_is_valid(value) virtual¶

Parameters:: value (GObject.Value) –
Return type:: bool

do_value_set_default(value) virtual¶

Parameters:: value (GObject.Value) –

do_value_validate(value) virtual¶

Parameters:: value (GObject.Value) –
Return type:: bool

do_values_cmp(value1, value2) virtual¶

Parameters:

value1 (GObject.Value) –
value2 (GObject.Value) –

Return type:

int