Virtual Method
GioActionGroupquery_action
since: 2.32
Declaration
gboolean
query_action (
GActionGroup* action_group,
const gchar* action_name,
gboolean* enabled,
const GVariantType** parameter_type,
const GVariantType** state_type,
GVariant** state_hint,
GVariant** state
)
Description
Queries all aspects of the named action within an action_group.
This function acquires the information available from
g_action_group_has_action(), g_action_group_get_action_enabled(),
g_action_group_get_action_parameter_type(),
g_action_group_get_action_state_type(),
g_action_group_get_action_state_hint() and
g_action_group_get_action_state() with a single function call.
This provides two main benefits.
The first is the improvement in efficiency that comes with not having
to perform repeated lookups of the action in order to discover
different things about it. The second is that implementing
GActionGroup can now be done by only overriding this one virtual function.
The interface provides a default implementation of this function that calls the individual functions, as required, to fetch the information. The interface also provides default implementations of those functions that call this function. All implementations, therefore, must override either this function or all of the others.
If the action exists, TRUE is returned and any of the requested
fields (as indicated by having a non-NULL reference passed in) are
filled. If the action doesn’t exist, FALSE is returned and the
fields may or may not have been modified.
Available since: 2.32
Parameters
action_name-
Type:
const gchar*The name of an action in the group.
The data is owned by the caller of the function. The value is a NUL terminated UTF-8 string. enabled-
Type:
gboolean*If the action is presently enabled.
The argument will be set by the function. parameter_type-
Type:
GVariantTypeThe parameter type, or
NULLif none needed.The argument will be set by the function. The argument can be NULL.The data is owned by the caller of the function. state_type-
Type:
GVariantTypeThe state type, or
NULLif stateless.The argument will be set by the function. The argument can be NULL.The data is owned by the caller of the function. state_hint-
Type:
GVariantThe state hint, or
NULLif none.The argument will be set by the function. The argument can be NULL.The called function takes ownership of the data, and is responsible for freeing it. state-
Type:
GVariantThe current state, or
NULLif stateless.The argument will be set by the function. The argument can be NULL.The called function takes ownership of the data, and is responsible for freeing it.