gi-gio-2.0.25: Gio bindings
Copyright Will Thompson Iñaki García Etxebarria and Jonas Platte LGPL-2.1 Iñaki García Etxebarria None Haskell2010

GI.Gio.Interfaces.ActionGroup

Description

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 actionGroupActivateAction. Activating an action may require a GVariant parameter. The required type of the parameter can be inquired with actionGroupGetActionParameterType. Actions may be disabled, see actionGroupGetActionEnabled. Activating a disabled action has no effect.

Actions may optionally have a state in the form of a GVariant. The current state of an action can be inquired with actionGroupGetActionState. Activating a stateful action may change its state, but it is also possible to set the state by calling actionGroupChangeActionState.

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 actionGroupListActions 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 - actionGroupGetActionEnabled 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 actionGroupListActions and actionGroupQueryAction. The other virtual functions should not be implemented - their "wrappers" are actually implemented with calls to actionGroupQueryAction.

Synopsis

# Exported types

newtype ActionGroup Source #

Memory-managed wrapper type.

Constructors

 ActionGroup (ManagedPtr ActionGroup)

#### Instances

Instances details
 Source # Instance detailsDefined in GI.Gio.Interfaces.ActionGroup Methods Source # Instance detailsDefined in GI.Gio.Interfaces.ActionGroup Methods Source # Convert ActionGroup to and from GValue with toGValue and fromGValue. Instance detailsDefined in GI.Gio.Interfaces.ActionGroup Methods Source # Instance detailsDefined in GI.Gio.Interfaces.ActionGroup Source # Instance detailsDefined in GI.Gio.Interfaces.ActionGroup type ParentTypes ActionGroup = '[Object]

A convenience alias for Nothing :: Maybe ActionGroup.

class (GObject o, IsDescendantOf ActionGroup o) => IsActionGroup o Source #

Type class for types which can be safely cast to ActionGroup, for instance with toActionGroup.

#### Instances

Instances details
 Source # Instance detailsDefined in GI.Gio.Interfaces.ActionGroup

toActionGroup :: (MonadIO m, IsActionGroup o) => o -> m ActionGroup Source #

Cast to ActionGroup, for types for which this is known to be safe. For general casts, use castTo.

# Methods

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of an action in the group -> m ()

Emits the actionAdded signal on actionGroup.

This function should only be called by ActionGroup implementations.

Since: 2.28

## actionEnabledChanged

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of an action in the group -> Bool enabled: whether or not the action is now enabled -> m ()

Emits the actionEnabledChanged signal on actionGroup.

This function should only be called by ActionGroup implementations.

Since: 2.28

## actionRemoved

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of an action in the group -> m ()

Emits the actionRemoved signal on actionGroup.

This function should only be called by ActionGroup implementations.

Since: 2.28

## actionStateChanged

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of an action in the group -> GVariant state: the new state of the named action -> m ()

Emits the actionStateChanged signal on actionGroup.

This function should only be called by ActionGroup implementations.

Since: 2.28

## activateAction

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of the action to activate -> Maybe GVariant parameter: parameters to the activation -> m ()

Activate the named action within actionGroup.

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 Nothing. See actionGroupGetActionParameterType.

Since: 2.28

## changeActionState

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of the action to request the change on -> GVariant value: the new state -> m ()

Request for the state of the named action within actionGroup to be changed to value.

The action must be stateful and value must be of the correct type. See actionGroupGetActionStateType.

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 actionGroupGetActionStateHint.

If the value GVariant is floating, it is consumed.

Since: 2.28

## getActionEnabled

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of the action to query -> m Bool Returns: whether or not the action is currently enabled

Checks if the named action within actionGroup is currently enabled.

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

Since: 2.28

## getActionParameterType

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of the action to query -> m (Maybe VariantType) Returns: the parameter type

Queries the type of the parameter that must be given when activating the named action within actionGroup.

When activating the action using actionGroupActivateAction, the GVariant given to that function must be of the type returned by this function.

In the case that this function returns Nothing, you must not give any GVariant, but Nothing 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.

Since: 2.28

## getActionState

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of the action to query -> m (Maybe GVariant) Returns: the current state of the action

Queries the current state of the named action within actionGroup.

If the action is not stateful then Nothing will be returned. If the action is stateful then the type of the return value is the type given by actionGroupGetActionStateType.

The return value (if non-Nothing) should be freed with variantUnref when it is no longer required.

Since: 2.28

## getActionStateHint

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of the action to query -> m (Maybe GVariant) Returns: the state range hint

Requests a hint about the valid range of values for the state of the named action within actionGroup.

If Nothing 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 GVariant array is returned then each item in the array is a possible value for the state. If a GVariant 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-Nothing) should be freed with variantUnref when it is no longer required.

Since: 2.28

## getActionStateType

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of the action to query -> m (Maybe VariantType) Returns: the state type, if the action is stateful

Queries the type of the state of the named action within actionGroup.

If the action is stateful then this function returns the VariantType of the state. All calls to actionGroupChangeActionState must give a GVariant of this type and actionGroupGetActionState will return a GVariant of the same type.

If the action is not stateful then this function will return Nothing. In that case, actionGroupGetActionState will return Nothing and you must not call actionGroupChangeActionState.

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.

Since: 2.28

## hasAction

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of the action to check for -> m Bool Returns: whether the named action exists

Checks if the named action exists within actionGroup.

Since: 2.28

## listActions

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> m [Text] Returns: a Nothing-terminated array of the names of the actions in the group

Lists the actions contained within actionGroup.

The caller is responsible for freeing the list with strfreev when it is no longer required.

Since: 2.28

## queryAction

Arguments

 :: (HasCallStack, MonadIO m, IsActionGroup a) => a actionGroup: a ActionGroup -> Text actionName: the name of an action in the group -> m (Bool, Bool, VariantType, VariantType, GVariant, GVariant) Returns: True if the action exists, else False

Queries all aspects of the named action within an actionGroup.

This function acquires the information available from actionGroupHasAction, actionGroupGetActionEnabled, actionGroupGetActionParameterType, actionGroupGetActionStateType, actionGroupGetActionStateHint and actionGroupGetActionState 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 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-Nothing reference passed in) are filled. If the action doesn't exist, False is returned and the fields may or may not have been modified.

Since: 2.32

# Signals

Arguments

 = Text actionName: the name of the action in actionGroup -> IO ()

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.

Since: 2.28

type C_ActionGroupActionAddedCallback = Ptr () -> CString -> Ptr () -> IO () Source #

Type for the callback on the (unwrapped) C side.

Connect a signal handler for the actionAdded signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after actionGroup #actionAdded callback


This signal admits a optional parameter detail. If it's not Nothing, we will connect to “action-added::detail” instead.

Wrap the callback into a GClosure.

Generate a function pointer callable from C code, from a C_ActionGroupActionAddedCallback.

A convenience synonym for Nothing :: Maybe ActionGroupActionAddedCallback.

Connect a signal handler for the actionAdded signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on actionGroup #actionAdded callback


This signal admits a optional parameter detail. If it's not Nothing, we will connect to “action-added::detail” instead.

Wrap a ActionGroupActionAddedCallback into a C_ActionGroupActionAddedCallback.

## actionEnabledChanged

Arguments

 = Text actionName: the name of the action in actionGroup -> Bool enabled: whether the action is enabled or not -> IO ()

Signals that the enabled status of the named action has changed.

Since: 2.28

type C_ActionGroupActionEnabledChangedCallback = Ptr () -> CString -> CInt -> Ptr () -> IO () Source #

Type for the callback on the (unwrapped) C side.

Connect a signal handler for the actionEnabledChanged signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after actionGroup #actionEnabledChanged callback


This signal admits a optional parameter detail. If it's not Nothing, we will connect to “action-enabled-changed::detail” instead.

Wrap the callback into a GClosure.

Generate a function pointer callable from C code, from a C_ActionGroupActionEnabledChangedCallback.

A convenience synonym for Nothing :: Maybe ActionGroupActionEnabledChangedCallback.

Connect a signal handler for the actionEnabledChanged signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on actionGroup #actionEnabledChanged callback


This signal admits a optional parameter detail. If it's not Nothing, we will connect to “action-enabled-changed::detail” instead.

Wrap a ActionGroupActionEnabledChangedCallback into a C_ActionGroupActionEnabledChangedCallback.

## actionRemoved

Arguments

 = Text actionName: the name of the action in actionGroup -> IO ()

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.

Since: 2.28

type C_ActionGroupActionRemovedCallback = Ptr () -> CString -> Ptr () -> IO () Source #

Type for the callback on the (unwrapped) C side.

Connect a signal handler for the actionRemoved signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after actionGroup #actionRemoved callback


This signal admits a optional parameter detail. If it's not Nothing, we will connect to “action-removed::detail” instead.

Wrap the callback into a GClosure.

Generate a function pointer callable from C code, from a C_ActionGroupActionRemovedCallback.

A convenience synonym for Nothing :: Maybe ActionGroupActionRemovedCallback.

Connect a signal handler for the actionRemoved signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on actionGroup #actionRemoved callback


This signal admits a optional parameter detail. If it's not Nothing, we will connect to “action-removed::detail” instead.

Wrap a ActionGroupActionRemovedCallback into a C_ActionGroupActionRemovedCallback.

## actionStateChanged

Arguments

 = Text actionName: the name of the action in actionGroup -> GVariant value: the new value of the state -> IO ()

Signals that the state of the named action has changed.

Since: 2.28

type C_ActionGroupActionStateChangedCallback = Ptr () -> CString -> Ptr GVariant -> Ptr () -> IO () Source #

Type for the callback on the (unwrapped) C side.

Connect a signal handler for the actionStateChanged signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after actionGroup #actionStateChanged callback


This signal admits a optional parameter detail. If it's not Nothing, we will connect to “action-state-changed::detail” instead.

Wrap the callback into a GClosure.

Generate a function pointer callable from C code, from a C_ActionGroupActionStateChangedCallback.

A convenience synonym for Nothing :: Maybe ActionGroupActionStateChangedCallback.

Connect a signal handler for the actionStateChanged signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on actionGroup #actionStateChanged callback


This signal admits a optional parameter detail. If it's not Nothing, we will connect to “action-state-changed::detail” instead.

Wrap a ActionGroupActionStateChangedCallback into a C_ActionGroupActionStateChangedCallback.