GObject.ParamSpec - Classes - GObject 2.0 (original) (raw)
g GObject.ParamSpec GObject.ParamSpec
Subclasses:
GObject.ParamSpecBoolean, GObject.ParamSpecBoxed, GObject.ParamSpecChar, GObject.ParamSpecDouble, GObject.ParamSpecEnum, GObject.ParamSpecFlags, GObject.ParamSpecFloat, GObject.ParamSpecGType, GObject.ParamSpecInt, GObject.ParamSpecInt64, GObject.ParamSpecLong, GObject.ParamSpecObject, GObject.ParamSpecOverride, GObject.ParamSpecParam, GObject.ParamSpecPointer, GObject.ParamSpecString, GObject.ParamSpecUChar, GObject.ParamSpecUInt, GObject.ParamSpecUInt64, GObject.ParamSpecULong, GObject.ParamSpecUnichar, GObject.ParamSpecValueArray, GObject.ParamSpecVariant
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 | GParamFlags flags for this parameter |
| g_type_instance | GObject.TypeInstance | r | private GTypeInstance portion |
| name | str | r | name of this parameter: always an interned string |
| owner_type | GObject.GType | r | 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 GValue type for this parameter |
Class Details¶
class GObject.ParamSpec¶
Abstract:
Yes
Structure:
GParamSpec encapsulates the metadata required to specify parameters, such as GObject 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 [func`GObject`.signal_new]).
When creating and looking up a GParamSpec, 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)[source]¶
Parameters:
name (str) – the canonical name of the property
Returns:
True if name is a valid property name, False otherwise.
Return type:
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 [class@GObject.ParamSpec#parameter-names]’ for details of the rules for valid names.
New in version 2.66.
Returns:
the short description of self.
Return type:
Get the short description of a GObject.ParamSpec.
Returns:
a pointer to a GObject.Value which must not be modified
Return type:
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.
Returns:
the name of self.
Return type:
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.
Returns:
the GQuark for self->name.
Return type:
Gets the GQuark for the name.
New in version 2.46.
Returns:
the nickname of self.
Return type:
Get the nickname of a GObject.ParamSpec.
Parameters:
quark (int) – a #GQuark, naming the user data pointer
Returns:
the user data pointer set, or None
Return type:
Gets back user data pointers stored via GObject.ParamSpec.set_qdata().
get_redirect_target()[source]¶
Returns:
paramspec to which requests on this paramspec should be redirected, or None if none.
Return type:
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)[source]¶
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. viaGLib.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.
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).
Parameters:
quark (int) – a #GQuark, naming the user data pointer
Returns:
the user data pointer set, or None
Return type:
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¶
The instance finalization function (optional), should chain up to the finalize method of the parent class.
do_value_is_valid(value) virtual¶
Parameters:
value (GObject.Value) –
Return type:
Checks if contents of value comply with the specifications set out by this type, without modifying the value. This vfunc is optional. If it isn’t set, GObject.Object will use value_validate.
New in version 2.74.
do_value_set_default(value) virtual¶
Parameters:
value (GObject.Value) –
Resets a value to the default value for this type (recommended, the default is GObject.Value.reset()), seeGObject.param_value_set_default().
do_value_validate(value) virtual¶
Parameters:
value (GObject.Value) –
Return type:
Ensures that the contents of value comply with the specifications set out by this type (optional), seeGObject.param_value_validate().
do_values_cmp(value1, value2) virtual¶
Parameters:
- value1 (GObject.Value) –
- value2 (GObject.Value) –
Return type:
Compares value1 with value2 according to this type (recommended, the default is memcmp()), see GObject.param_values_cmp().