ActionGroup

ActionGroup

Object Hierarchy:

Description:

public interface ActionGroup : Object

ActionGroup 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 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 activate_action. Activating an action may require a Variant parameter. The required type of the parameter can be inquired with get_action_parameter_type. Actions may be disabled, see get_action_enabled. Activating a disabled action has no effect.

Actions may optionally have a state in the form of a Variant. The current state of an action can be inquired with get_action_state. Activating a stateful action may change its state, but it is also possible to set the state by calling 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 list_actions take the name of an action as an argument.

The ActionGroup 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 - get_action_enabled but not an equivalent set call.

Signals are emitted on the action group in response to state changes on individual actions.

Implementations of ActionGroup should provide implementations for the virtual functions list_actions and query_action. The other virtual functions should not be implemented - their "wrappers" are actually implemented with calls to query_action.

All known implementing classes:

Application

DBusActionGroup

SimpleActionGroup

All known sub-interfaces:

RemoteActionGroup

Namespace: GLib

Package: gio-2.0

Content:

Methods:

public abstract void activate_action (string action_name, Variant? parameter)
Activate the named action within this .
public abstract void change_action_state (string action_name, Variant value)
Request for the state of the named action within this to be changed to value.
public abstract bool get_action_enabled (string action_name)
Checks if the named action within this is currently enabled.
public abstract unowned VariantType? get_action_parameter_type (string action_name)
Queries the type of the parameter that must be given when activating the named action within this.
public abstract Variant? get_action_state (string action_name)
Queries the current state of the named action within this.
public abstract Variant? get_action_state_hint (string action_name)
Requests a hint about the valid range of values for the state of the named action within this.
public abstract unowned VariantType? get_action_state_type (string action_name)
Queries the type of the state of the named action within this.
public abstract bool has_action (string action_name)
Checks if the named action exists within this.
public abstract string[] list_actions ()
Lists the actions contained within this .
public virtual bool query_action (string action_name, out bool enabled, out VariantType parameter_type, out VariantType state_type, out Variant state_hint, out Variant state)
Queries all aspects of the named action within an this.

Signals:

public virtual signal void action_added (string action_name)
Signals that a new action was just added to the group.
public virtual signal void action_enabled_changed (string action_name, bool enabled)
Signals that the enabled status of the named action has changed.
public virtual signal void action_removed (string action_name)
Signals that an action is just about to be removed from the group.
public virtual signal void action_state_changed (string action_name, Variant state)
Signals that the state of the named action has changed.

Inherited Members:

All known members inherited from class GLib.Object