Gio.ActionGroup - Interfaces - Gio 2.0 (original) (raw)
g GObject.GInterface GObject.GInterface Gio.ActionGroup Gio.ActionGroup GObject.GInterface->Gio.ActionGroup
Implementations:
Gio.Application, Gio.DBusActionGroup, Gio.SimpleActionGroup
Methods¶
| action_added (action_name) |
|---|
| action_enabled_changed (action_name, enabled) |
| action_removed (action_name) |
| action_state_changed (action_name, state) |
| activate_action (action_name, parameter) |
| change_action_state (action_name, value) |
| get_action_enabled (action_name) |
| get_action_parameter_type (action_name) |
| get_action_state (action_name) |
| get_action_state_hint (action_name) |
| get_action_state_type (action_name) |
| has_action (action_name) |
| list_actions () |
| query_action (action_name) |
Virtual Methods¶
| do_action_added (action_name) |
|---|
| do_action_enabled_changed (action_name, enabled) |
| do_action_removed (action_name) |
| do_action_state_changed (action_name, state) |
| do_activate_action (action_name, parameter) |
| do_change_action_state (action_name, value) |
| do_get_action_enabled (action_name) |
| do_get_action_parameter_type (action_name) |
| do_get_action_state (action_name) |
| do_get_action_state_hint (action_name) |
| do_get_action_state_type (action_name) |
| do_has_action (action_name) |
| do_list_actions () |
| do_query_action (action_name) |
Properties¶
None
Signals¶
| Name | Short Description |
|---|---|
| action-added | Signals that a new action was just added to the group. |
| action-enabled-changed | Signals that the enabled status of the named action has changed. |
| action-removed | Signals that an action is just about to be removed from the group. |
| action-state-changed | Signals that the state of the named action has changed. |
Fields¶
None
Class Details¶
class Gio.ActionGroup¶
Bases:
Structure:
GActionGroup represents a group of actions.
Actions can be used to expose functionality in a structured way, either from one part of a program to another, or to the outside world. Action groups are often used together with a [type`Gio`.MenuModel] that provides additional representation data for displaying the actions to the user, e.g. in a menu.
The main way to interact with the actions in a GActionGroup is to activate them with [method`Gio`.ActionGroup.activate_action]. Activating an action may require a [type`GLib`.Variant] parameter. The required type of the parameter can be inquired with [method`Gio`.ActionGroup.get_action_parameter_type]. Actions may be disabled, see [method`Gio`.ActionGroup.get_action_enabled]. Activating a disabled action has no effect.
Actions may optionally have a state in the form of a [type`GLib`.Variant]. The current state of an action can be inquired with [method`Gio`.ActionGroup.get_action_state]. Activating a stateful action may change its state, but it is also possible to set the state by calling [method`Gio`.ActionGroup.change_action_state].
As typical example, consider a text editing application which has an option to change the current font to ‘bold’. A good way to represent this would be a stateful action, with a boolean state. Activating the action would toggle the state.
Each action in the group has a unique name (which is a string). All method calls, except [method`Gio`.ActionGroup.list_actions] take the name of an action as an argument.
The GActionGroup API is meant to be the ‘public’ API to the action group. The calls here are exactly the interaction that ‘external forces’ (eg: UI, incoming D-Bus messages, etc.) are supposed to have with actions. ‘Internal’ APIs (ie: ones meant only to be accessed by the action group implementation) are found on subclasses. This is why you will find – for example – [method`Gio`.ActionGroup.get_action_enabled] but not an equivalent set_action_enabled() method.
Signals are emitted on the action group in response to state changes on individual actions.
Implementations of GActionGroup should provide implementations for the virtual functions [method`Gio`.ActionGroup.list_actions] and [method`Gio`.ActionGroup.query_action]. The other virtual functions should not be implemented — their ‘wrappers’ are actually implemented with calls to [method`Gio`.ActionGroup.query_action].
action_added(action_name)[source]¶
Parameters:
action_name (str) – the name of an action in the group
Emits the [signal`Gio`.ActionGroup::action-added] signal on self.
This function should only be called by [type`Gio`.ActionGroup] implementations.
New in version 2.28.
action_enabled_changed(action_name, enabled)[source]¶
Parameters:
- action_name (str) – the name of an action in the group
- enabled (bool) – whether the action is now enabled
Emits the [signal`Gio`.ActionGroup::action-enabled-changed] signal on self.
This function should only be called by [type`Gio`.ActionGroup] implementations.
New in version 2.28.
action_removed(action_name)[source]¶
Parameters:
action_name (str) – the name of an action in the group
Emits the [signal`Gio`.ActionGroup::action-removed] signal on self.
This function should only be called by [type`Gio`.ActionGroup] implementations.
New in version 2.28.
action_state_changed(action_name, state)[source]¶
Parameters:
- action_name (str) – the name of an action in the group
- state (GLib.Variant) – the new state of the named action
Emits the [signal`Gio`.ActionGroup::action-state-changed] signal on self.
This function should only be called by [type`Gio`.ActionGroup] implementations.
New in version 2.28.
activate_action(action_name, parameter)[source]¶
Parameters:
- action_name (str) – the name of the action to activate
- parameter (GLib.Variant or None) – parameters to the activation
Activate the named action within self.
If the action is expecting a parameter, then the correct type of parameter must be given as parameter. If the action is expecting no parameters then parameter must be NULL. See [method`Gio`.ActionGroup.get_action_parameter_type].
If the [type`Gio`.ActionGroup] implementation supports asynchronous remote activation over D-Bus, this call may return before the relevant D-Bus traffic has been sent, or any replies have been received. In order to block on such asynchronous activation calls, [method`Gio`.DBusConnection.flush] should be called prior to the code, which depends on the result of the action activation. Without flushing the D-Bus connection, there is no guarantee that the action would have been activated.
The following code which runs in a remote app instance, shows an example of a ‘quit’ action being activated on the primary app instance over D-Bus. Here [method`Gio`.DBusConnection.flush] is called before exit(). Without g_dbus_connection_flush(), the ‘quit’ action may fail to be activated on the primary instance.
```c // call ‘quit’ action on primary instanceGio.ActionGroup.activate_action (G_ACTION_GROUP (app), “quit”, None);
// make sure the action is activated nowGio.DBusConnection.flush (…);
g_debug (“Application has been terminated. Exiting.”);
exit (0); ```
New in version 2.28.
change_action_state(action_name, value)[source]¶
Parameters:
- action_name (str) – the name of the action to request the change on
- value (GLib.Variant) – the new state
Request for the state of the named action within self to be changed to value.
The action must be stateful and value must be of the correct type. See [method`Gio`.ActionGroup.get_action_state_type].
This call merely requests a change. The action may refuse to change its state or may change its state to something other than value. See [method`Gio`.ActionGroup.get_action_state_hint].
If the value GLib.Variant is floating, it is consumed.
New in version 2.28.
get_action_enabled(action_name)[source]¶
Parameters:
action_name (str) – the name of the action to query
Returns:
whether the action is currently enabled
Return type:
Checks if the named action within self is currently enabled.
An action must be enabled in order to be activated or in order to have its state changed from outside callers.
New in version 2.28.
get_action_parameter_type(action_name)[source]¶
Parameters:
action_name (str) – the name of the action to query
Returns:
the parameter type
Return type:
Queries the type of the parameter that must be given when activating the named action within self.
When activating the action using [method`Gio`.ActionGroup.activate_action], the [type`GLib`.Variant] given to that function must be of the type returned by this function.
In the case that this function returns NULL, you must not give any [type`GLib`.Variant], but NULL instead.
The parameter type of a particular action will never change but it is possible for an action to be removed and for a new action to be added with the same name but a different parameter type.
New in version 2.28.
get_action_state(action_name)[source]¶
Parameters:
action_name (str) – the name of the action to query
Returns:
the current state of the action
Return type:
GLib.Variant or None
Queries the current state of the named action within self.
If the action is not stateful then NULL will be returned. If the action is stateful then the type of the return value is the type given by [method`Gio`.ActionGroup.get_action_state_type].
The return value (if non-NULL) should be freed with [method`GLib`.Variant.unref] when it is no longer required.
New in version 2.28.
get_action_state_hint(action_name)[source]¶
Parameters:
action_name (str) – the name of the action to query
Returns:
the state range hint
Return type:
GLib.Variant or None
Requests a hint about the valid range of values for the state of the named action within self.
If NULL is returned it either means that the action is not stateful or that there is no hint about the valid range of values for the state of the action.
If a [type`GLib`.Variant] array is returned then each item in the array is a possible value for the state. If a [type`GLib`.Variant] pair (ie: two-tuple) is returned then the tuple specifies the inclusive lower and upper bound of valid values for the state.
In any case, the information is merely a hint. It may be possible to have a state value outside of the hinted range and setting a value within the range may fail.
The return value (if non-NULL) should be freed with [method`GLib`.Variant.unref] when it is no longer required.
New in version 2.28.
get_action_state_type(action_name)[source]¶
Parameters:
action_name (str) – the name of the action to query
Returns:
the state type, if the action is stateful
Return type:
Queries the type of the state of the named action withinself.
If the action is stateful then this function returns the [type`GLib`.VariantType] of the state. All calls to [method`Gio`.ActionGroup.change_action_state] must give a [type`GLib`.Variant] of this type and [method`Gio`.ActionGroup.get_action_state] will return a [type`GLib`.Variant] of the same type.
If the action is not stateful then this function will return NULL. In that case, [method`Gio`.ActionGroup.get_action_state] will return NULLand you must not call [method`Gio`.ActionGroup.change_action_state].
The state type of a particular action will never change but it is possible for an action to be removed and for a new action to be added with the same name but a different state type.
New in version 2.28.
has_action(action_name)[source]¶
Parameters:
action_name (str) – the name of the action to check for
Returns:
whether the named action exists
Return type:
Checks if the named action exists within self.
New in version 2.28.
Returns:
a NULL-terminated array of the names of the actions in the group
Return type:
[str]
Lists the actions contained within self.
The caller is responsible for freeing the list with [func`GLib`.strfreev] when it is no longer required.
New in version 2.28.
query_action(action_name)[source]¶
Parameters:
action_name (str) – the name of an action in the group
Returns:
TRUE if the action exists, else FALSE
enabled:
if the action is presently enabled
parameter_type:
the parameter type, or NULL if none needed
state_type:
the state type, or NULL if stateless
state_hint:
the state hint, or NULL if none
state:
the current state, or NULL if stateless
Return type:
(bool, enabled: bool, parameter_type: GLib.VariantType, state_type: GLib.VariantType, state_hint: GLib.Variant, state: GLib.Variant)
Queries all aspects of the named action within an self.
This function acquires the information available from [method`Gio`.ActionGroup.has_action], [method`Gio`.ActionGroup.get_action_enabled], [method`Gio`.ActionGroup.get_action_parameter_type], [method`Gio`.ActionGroup.get_action_state_type], [method`Gio`.ActionGroup.get_action_state_hint] and [method`Gio`.ActionGroup.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 [type`Gio`.ActionGroup] 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.
New in version 2.32.
do_action_added(action_name) virtual¶
Parameters:
action_name (str) – the name of an action in the group
Emits the [signal`Gio`.ActionGroup::action-added] signal on action_group.
This function should only be called by [type`Gio`.ActionGroup] implementations.
New in version 2.28.
do_action_enabled_changed(action_name, enabled) virtual¶
Parameters:
- action_name (str) – the name of an action in the group
- enabled (bool) – whether the action is now enabled
Emits the [signal`Gio`.ActionGroup::action-enabled-changed] signal on action_group.
This function should only be called by [type`Gio`.ActionGroup] implementations.
New in version 2.28.
do_action_removed(action_name) virtual¶
Parameters:
action_name (str) – the name of an action in the group
Emits the [signal`Gio`.ActionGroup::action-removed] signal on action_group.
This function should only be called by [type`Gio`.ActionGroup] implementations.
New in version 2.28.
do_action_state_changed(action_name, state) virtual¶
Parameters:
- action_name (str) – the name of an action in the group
- state (GLib.Variant) – the new state of the named action
Emits the [signal`Gio`.ActionGroup::action-state-changed] signal on action_group.
This function should only be called by [type`Gio`.ActionGroup] implementations.
New in version 2.28.
do_activate_action(action_name, parameter) virtual¶
Parameters:
- action_name (str) – the name of the action to activate
- parameter (GLib.Variant or None) – parameters to the activation
Activate the named action within action_group.
If the action is expecting a parameter, then the correct type of parameter must be given as parameter. If the action is expecting no parameters then parameter must be NULL. See [method`Gio`.ActionGroup.get_action_parameter_type].
If the [type`Gio`.ActionGroup] implementation supports asynchronous remote activation over D-Bus, this call may return before the relevant D-Bus traffic has been sent, or any replies have been received. In order to block on such asynchronous activation calls, [method`Gio`.DBusConnection.flush] should be called prior to the code, which depends on the result of the action activation. Without flushing the D-Bus connection, there is no guarantee that the action would have been activated.
The following code which runs in a remote app instance, shows an example of a ‘quit’ action being activated on the primary app instance over D-Bus. Here [method`Gio`.DBusConnection.flush] is called before exit(). Without g_dbus_connection_flush(), the ‘quit’ action may fail to be activated on the primary instance.
```c // call ‘quit’ action on primary instanceGio.ActionGroup.activate_action (G_ACTION_GROUP (app), “quit”, None);
// make sure the action is activated nowGio.DBusConnection.flush (…);
g_debug (“Application has been terminated. Exiting.”);
exit (0); ```
New in version 2.28.
do_change_action_state(action_name, value) virtual¶
Parameters:
- action_name (str) – the name of the action to request the change on
- value (GLib.Variant) – the new state
Request for the state of the named action within action_group to be changed to value.
The action must be stateful and value must be of the correct type. See [method`Gio`.ActionGroup.get_action_state_type].
This call merely requests a change. The action may refuse to change its state or may change its state to something other than value. See [method`Gio`.ActionGroup.get_action_state_hint].
If the value GLib.Variant is floating, it is consumed.
New in version 2.28.
do_get_action_enabled(action_name) virtual¶
Parameters:
action_name (str) – the name of the action to query
Returns:
whether the action is currently enabled
Return type:
Checks if the named action within action_group is currently enabled.
An action must be enabled in order to be activated or in order to have its state changed from outside callers.
New in version 2.28.
do_get_action_parameter_type(action_name) virtual¶
Parameters:
action_name (str) – the name of the action to query
Returns:
the parameter type
Return type:
Queries the type of the parameter that must be given when activating the named action within action_group.
When activating the action using [method`Gio`.ActionGroup.activate_action], the [type`GLib`.Variant] given to that function must be of the type returned by this function.
In the case that this function returns NULL, you must not give any [type`GLib`.Variant], but NULL instead.
The parameter type of a particular action will never change but it is possible for an action to be removed and for a new action to be added with the same name but a different parameter type.
New in version 2.28.
do_get_action_state(action_name) virtual¶
Parameters:
action_name (str) – the name of the action to query
Returns:
the current state of the action
Return type:
GLib.Variant or None
Queries the current state of the named action within action_group.
If the action is not stateful then NULL will be returned. If the action is stateful then the type of the return value is the type given by [method`Gio`.ActionGroup.get_action_state_type].
The return value (if non-NULL) should be freed with [method`GLib`.Variant.unref] when it is no longer required.
New in version 2.28.
do_get_action_state_hint(action_name) virtual¶
Parameters:
action_name (str) – the name of the action to query
Returns:
the state range hint
Return type:
GLib.Variant or None
Requests a hint about the valid range of values for the state of the named action within action_group.
If NULL is returned it either means that the action is not stateful or that there is no hint about the valid range of values for the state of the action.
If a [type`GLib`.Variant] array is returned then each item in the array is a possible value for the state. If a [type`GLib`.Variant] pair (ie: two-tuple) is returned then the tuple specifies the inclusive lower and upper bound of valid values for the state.
In any case, the information is merely a hint. It may be possible to have a state value outside of the hinted range and setting a value within the range may fail.
The return value (if non-NULL) should be freed with [method`GLib`.Variant.unref] when it is no longer required.
New in version 2.28.
do_get_action_state_type(action_name) virtual¶
Parameters:
action_name (str) – the name of the action to query
Returns:
the state type, if the action is stateful
Return type:
Queries the type of the state of the named action withinaction_group.
If the action is stateful then this function returns the [type`GLib`.VariantType] of the state. All calls to [method`Gio`.ActionGroup.change_action_state] must give a [type`GLib`.Variant] of this type and [method`Gio`.ActionGroup.get_action_state] will return a [type`GLib`.Variant] of the same type.
If the action is not stateful then this function will return NULL. In that case, [method`Gio`.ActionGroup.get_action_state] will return NULLand you must not call [method`Gio`.ActionGroup.change_action_state].
The state type of a particular action will never change but it is possible for an action to be removed and for a new action to be added with the same name but a different state type.
New in version 2.28.
do_has_action(action_name) virtual¶
Parameters:
action_name (str) – the name of the action to check for
Returns:
whether the named action exists
Return type:
Checks if the named action exists within action_group.
New in version 2.28.
do_list_actions() virtual¶
Returns:
a NULL-terminated array of the names of the actions in the group
Return type:
[str]
Lists the actions contained within action_group.
The caller is responsible for freeing the list with [func`GLib`.strfreev] when it is no longer required.
New in version 2.28.
do_query_action(action_name) virtual¶
Parameters:
action_name (str) – the name of an action in the group
Returns:
TRUE if the action exists, else FALSE
enabled:
if the action is presently enabled
parameter_type:
the parameter type, or NULL if none needed
state_type:
the state type, or NULL if stateless
state_hint:
the state hint, or NULL if none
state:
the current state, or NULL if stateless
Return type:
(bool, enabled: bool, parameter_type: GLib.VariantType, state_type: GLib.VariantType, state_hint: GLib.Variant, state: GLib.Variant)
Queries all aspects of the named action within an action_group.
This function acquires the information available from [method`Gio`.ActionGroup.has_action], [method`Gio`.ActionGroup.get_action_enabled], [method`Gio`.ActionGroup.get_action_parameter_type], [method`Gio`.ActionGroup.get_action_state_type], [method`Gio`.ActionGroup.get_action_state_hint] and [method`Gio`.ActionGroup.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 [type`Gio`.ActionGroup] 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.
New in version 2.32.
Signal Details¶
Gio.ActionGroup.signals.action_added(action_group, action_name)¶
Signal Name:
action-added
Flags:
Parameters:
- action_group (Gio.ActionGroup) – The object which received the signal
- action_name (str) – the name of the action in self
Signals that a new action was just added to the group.
This signal is emitted after the action has been added and is now visible.
New in version 2.28.
Gio.ActionGroup.signals.action_enabled_changed(action_group, action_name, enabled)¶
Signal Name:
action-enabled-changed
Flags:
Parameters:
- action_group (Gio.ActionGroup) – The object which received the signal
- action_name (str) – the name of the action in self
- enabled (bool) – whether the action is enabled
Signals that the enabled status of the named action has changed.
New in version 2.28.
Gio.ActionGroup.signals.action_removed(action_group, action_name)¶
Signal Name:
action-removed
Flags:
Parameters:
- action_group (Gio.ActionGroup) – The object which received the signal
- action_name (str) – the name of the action in self
Signals that an action is just about to be removed from the group.
This signal is emitted before the action is removed, so the action is still visible and can be queried from the signal handler.
New in version 2.28.
Gio.ActionGroup.signals.action_state_changed(action_group, action_name, value)¶
Signal Name:
action-state-changed
Flags:
RUN_LAST, DETAILED, MUST_COLLECT
Parameters:
- action_group (Gio.ActionGroup) – The object which received the signal
- action_name (str) – the name of the action in self
- value (GLib.Variant) – the new value of the state
Signals that the state of the named action has changed.
New in version 2.28.