Safe Haskell	None
Language	Haskell2010

GI.Gtk.Declarative.EventSource

Description

Event handling for declarative widgets.

Synopsis

class EventSource widget where
data Subscription
fromCancellation :: IO () -> Subscription
cancel :: Subscription -> IO ()

Documentation

class EventSource widget where Source #

An EventSource can be subscribed to, with a callback, returning a Subscription.

Minimal complete definition

subscribe

Methods

subscribe Source #

Arguments

:: widget event	Declarative widget with event handlers.
-> SomeState	State of rendered widget tree.
-> (event -> IO ())	Event callback, invoked on each emitted event until the `Subscription` is cancelled, or widget is otherwise destroyed.
-> IO Subscription	A `Subscription` is returned, which can be cancelled.

Instances

EventSource Widget Source #
Instance details Defined in GI.Gtk.Declarative.Markup Methods subscribe :: Widget event -> SomeState -> (event -> IO ()) -> IO Subscription Source #
EventSource BoxChild Source #
Instance details Defined in GI.Gtk.Declarative.Container.Box Methods subscribe :: BoxChild event -> SomeState -> (event -> IO ()) -> IO Subscription Source #
EventSource MenuItem Source #
Instance details Defined in GI.Gtk.Declarative.Container.MenuItem Methods subscribe :: MenuItem event -> SomeState -> (event -> IO ()) -> IO Subscription Source #
EventSource (SingleWidget widget) Source #
Instance details Defined in GI.Gtk.Declarative.SingleWidget Methods subscribe :: SingleWidget widget event -> SomeState -> (event -> IO ()) -> IO Subscription Source #
(BinChild parent child, EventSource child) => EventSource (Bin parent child) Source #
Instance details Defined in GI.Gtk.Declarative.Bin Methods subscribe :: Bin parent child event -> SomeState -> (event -> IO ()) -> IO Subscription Source #
(Typeable child, EventSource child) => EventSource (Container widget (Children child)) Source #
Instance details Defined in GI.Gtk.Declarative.Container Methods subscribe :: Container widget (Children child) event -> SomeState -> (event -> IO ()) -> IO Subscription Source #

data Subscription Source #

A Subscription contains zero or more cancellation actions for connected handlers (to a tree of widgets.) When subscribing to a container widget, all child widgets are also subscribed to, and the Subscriptions are combined using the Semigroup instance.

Instances

Semigroup Subscription Source #
Instance details Defined in GI.Gtk.Declarative.EventSource Methods (<>) :: Subscription -> Subscription -> Subscription # sconcat :: NonEmpty Subscription -> Subscription # stimes :: Integral b => b -> Subscription -> Subscription #
Monoid Subscription Source #
Instance details Defined in GI.Gtk.Declarative.EventSource Methods mempty :: Subscription # mappend :: Subscription -> Subscription -> Subscription # mconcat :: [Subscription] -> Subscription #

fromCancellation :: IO () -> Subscription Source #

Create a subscription from a cancellation IO action.

cancel :: Subscription -> IO () Source #

Cancel a Subscription, meaning that the callback will not be invoked on any subsequent signal emissions.