g_simple_action_new ()

GSimpleAction *
g_simple_action_new (const gchar *name,
                     const GVariantType *parameter_type);

Creates a new action.

The created action is stateless. See g_simple_action_new_stateful().

Since 2.28

g_simple_action_new_stateful ()

GSimpleAction *
g_simple_action_new_stateful (const gchar *name,
                              const GVariantType *parameter_type,
                              GVariant *state);

Creates a new stateful action.

state is the initial state of the action. All future state values must have the same GVariantType as the initial state.

If the state GVariant is floating, it is consumed.

Since 2.28

g_simple_action_set_enabled ()

void
g_simple_action_set_enabled (GSimpleAction *simple,
                             gboolean enabled);

Sets the action as enabled or not.

An action must be enabled in order to be activated or in order to have its state changed from outside callers.

This should only be called by the implementor of the action. Users of the action should not attempt to modify its enabled flag.

Since 2.28

g_simple_action_set_state ()

void
g_simple_action_set_state (GSimpleAction *simple,
                           GVariant *value);

Sets the state of the action.

This directly updates the 'state' property to the given value.

This should only be called by the implementor of the action. Users of the action should not attempt to directly modify the 'state' property. Instead, they should call g_action_change_state() to request the change.

If the value GVariant is floating, it is consumed.

Since 2.30

GSimpleAction

typedef struct _GSimpleAction GSimpleAction;

The “enabled” property

  “enabled”                  gboolean

If action is currently enabled.

If the action is disabled then calls to g_action_activate() and g_action_change_state() have no effect.

Flags: Read / Write

Default value: TRUE

Since 2.28

The “name” property

  “name”                     gchar *

The name of the action. This is mostly meaningful for identifying the action once it has been added to a GSimpleActionGroup.

Flags: Read / Write / Construct Only

Default value: NULL

Since 2.28

The “parameter-type” property

  “parameter-type”           GVariantType *

The type of the parameter that must be given when activating the action.

Flags: Read / Write / Construct Only

Since 2.28

The “state” property

  “state”                    GVariant *

The state of the action, or NULL if the action is stateless.

Flags: Read / Write / Construct

Allowed values: GVariant<*>

Default value: NULL

Since 2.28

The “state-type” property

  “state-type”               GVariantType *

The GVariantType of the state that the action has, or NULL if the action is stateless.

Flags: Read

Since 2.28

The “activate” signal

void
user_function (GSimpleAction *simple,
               GVariant      *parameter,
               gpointer       user_data)

Indicates that the action was just activated.

parameter will always be of the expected type. In the event that an incorrect type was given, no signal will be emitted.

Since GLib 2.40, if no handler is connected to this signal then the default behaviour for boolean-stated actions with a NULL parameter type is to toggle them via the “change-state” signal. For stateful actions where the state type is equal to the parameter type, the default is to forward them directly to “change-state”. This should allow almost all users of GSimpleAction to connect only one handler or the other.

Flags: Run Last

Since 2.28

The “change-state” signal

void
user_function (GSimpleAction *simple,
               GVariant      *value,
               gpointer       user_data)

Indicates that the action just received a request to change its state.

value will always be of the correct state type. In the event that an incorrect type was given, no signal will be emitted.

If no handler is connected to this signal then the default behaviour is to call g_simple_action_set_state() to set the state to the requested value. If you connect a signal handler then no default action is taken. If the state should change then you must call g_simple_action_set_state() from the handler.

An example of a 'change-state' handler:

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static void
change_volume_state (GSimpleAction *action,
                     GVariant      *value,
                     gpointer       user_data)
{
  gint requested;

  requested = g_variant_get_int32 (value);

  // Volume only goes from 0 to 10
  if (0 <= requested && requested <= 10)
    g_simple_action_set_state (action, value);
}

The handler need not set the state to the requested value. It could set it to any value at all, or take some other action.

Flags: Run Last

Since 2.30