Class
GioPropertyAction
since: 2.38
Description
final class Gio.PropertyAction : GObject.Object {
/* No available fields */
}A GPropertyAction is a way to get a GAction with a state value
reflecting and controlling the value of a GObject property.
The state of the action will correspond to the value of the property.
Changing it will change the property (assuming the requested value
matches the requirements as specified in the GParamSpec).
Only the most common types are presently supported. Booleans are mapped to booleans, strings to strings, signed/unsigned integers to int32/uint32 and floats and doubles to doubles.
If the property is an enum then the state will be string-typed and
conversion will automatically be performed between the enum value and
‘nick’ string as per the GEnumValue table.
Flags types are not currently supported.
Properties of object types, boxed types and pointer types are not supported and probably never will be.
Properties of GVariant types are not currently supported.
If the property is boolean-valued then the action will have a NULL
parameter type, and activating the action (with no parameter) will
toggle the value of the property.
In all other cases, the parameter type will correspond to the type of the property.
The general idea here is to reduce the number of locations where a
particular piece of state is kept (and therefore has to be synchronised
between). GPropertyAction does not have a separate state that is kept
in sync with the property value — its state is the property value.
For example, it might be useful to create a GAction corresponding
to the visible-child-name property of a GtkStack
so that the current page can be switched from a menu. The active radio
indication in the menu is then directly determined from the active page of
the GtkStack.
An anti-example would be binding the active-id property on a
GtkComboBox. This is
because the state of the combo box itself is probably uninteresting and is
actually being used to control something else.
Another anti-example would be to bind to the visible-child-name
property of a GtkStack if
this value is actually stored in GSettings. In that case, the
real source of the value is* GSettings. If you want
a GAction to control a setting stored in GSettings,
see g_settings_create_action() instead, and possibly combine its
use with g_settings_bind().
Available since: 2.38
Constructors
g_property_action_new
Creates a GAction corresponding to the value of property
property_name on object.
since: 2.38
Instance methods
Methods inherited from GAction (8)
g_action_activate
Activates the action.
since: 2.28
g_action_change_state
Request for the state of action to be changed to value.
since: 2.30
g_action_get_enabled
Checks if action is currently enabled.
since: 2.28
g_action_get_name
Queries the name of action.
since: 2.28
g_action_get_parameter_type
Queries the type of the parameter that must be given when activating
action.
since: 2.28
g_action_get_state
Queries the current state of action.
since: 2.28
g_action_get_state_hint
Requests a hint about the valid range of values for the state of
action.
since: 2.28
g_action_get_state_type
Queries the type of the state of action.
since: 2.28
Properties
Gio.PropertyAction:invert-boolean
If TRUE, the state of the action will be the negation of the
property value, provided the property is boolean.
since: 2.46
Gio.PropertyAction:name
The name of the action. This is mostly meaningful for identifying
the action once it has been added to a GActionMap.
since: 2.38
Gio.PropertyAction:parameter-type
The type of the parameter that must be given when activating the action.
since: 2.38
Gio.PropertyAction:state-type
The GVariantType of the state that the action has, or NULL if the
action is stateless.
since: 2.38
Properties inherited from GAction (5)
GAction:enabled
If action is currently enabled.
since: 2.28
GAction:name
The name of the action. This is mostly meaningful for identifying
the action once it has been added to a GActionGroup. It is immutable.
since: 2.28
GAction:parameter-type
The type of the parameter that must be given when activating the
action. This is immutable, and may be NULL if no parameter is needed when
activating the action.
since: 2.28
GAction:state
The state of the action, or NULL if the action is stateless.
since: 2.28
GAction:state-type
The GVariantType of the state that the action has, or NULL if the
action is stateless. This is immutable.
since: 2.28
Signals
Signals inherited from GObject (1)
GObject::notify
The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.