Reflex.Dom.Retractable.Class

Tagless final interface to the retractable stack of widgets. To use the API drop retractStack into your code where you want to display widgets with history. For instance, turn all your frontend into retractable widget:

import Control.Monad
import Reflex.Dom
import Reflex.Dom.Retractable.Class

frontend :: (MonadWidget t m, MonadRetract t m) => m ()
frontend = void $ retractStack $ pageA 42

pageA :: (MonadWidget t m, MonadRetract t m) => Int -> m ()
pageA n = do
   e <- button "Go page B"
   void $ nextWidget $ ffor e $ const Retractable {
       retractableNext = pageB $ n + 1
     , retractablePrev = Just $ pure $ pageA n
     }

pageB :: (MonadWidget t m, MonadRetract t m) => Int -> m ()
pageB n = do
  e <- button "Go page A"
  void $ nextWidget $ ffor e $ const  Retractable {
       retractableNext = pageA $ n + 1
     , retractablePrev = Just $ pure $ pageB n
     }

Documentation

data Retractable t m

Information about widget that attaches information how to return to the widget.

Constructors

Retractable

Fields

• retractableNext :: m ()

  Which widget we are switching in

• retractablePrev :: Maybe (Dynamic t (m ()))

  Possible return to the current widget. Nothing means that the current widget is not rembered in retract stack and is forgoten. Dynamic allows to save internal state of widget on return.

Instances

Generic (Retractable t m)

Defined in Reflex.Dom.Retractable.Class

Associated Types

type Rep (Retractable t m) :: * -> *

Methods

from :: Retractable t m -> Rep (Retractable t m) x

to :: Rep (Retractable t m) x -> Retractable t m

type Rep (Retractable t m)

Defined in Reflex.Dom.Retractable.Class

type Rep (Retractable t m) = D1 (MetaData "Retractable" "Reflex.Dom.Retractable.Class" "reflex-dom-retractable-0.1.0.0-inplace" False) (C1 (MetaCons "Retractable" PrefixI True) (S1 (MetaSel (Just "retractableNext") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (m ())) :*: S1 (MetaSel (Just "retractablePrev") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Maybe (Dynamic t (m ()))))))

morphRetractable :: Reflex t => (forall a. n a -> m a) -> Retractable t n -> Retractable t m

Helper to transform underlying monad in Retractable

class (MonadHold t m, MonadFix m, Reflex t, Adjustable t m) => MonadRetract t m where

Defines context of widget that can switch control to next widget and can be returned back with preserving of state.

Minimal complete definition

nextWidget, retract, wipeRetract, nextWidgetEvent, retractEvent, wipeRetractEvent, getRetractStack, withRetractStack

Methods

nextWidget :: Event t (Retractable t m) -> m (Event t ())

Switch current widget to the next widget. Returns event that fires when the switching is about to happen.

retract :: Event t () -> m (Event t ())

Switch to previous widget in stack. Returns event that fires when the switchin is about to happen.

wipeRetract :: Event t (Maybe Int) -> m (Event t ())

Wipe retract history to the given amount of items (or all if Nothing is passed). Returns event that fires when the history was changed.

nextWidgetEvent :: m (Event t (Retractable t m))

Get event that fires when any of input events in nextWidget is triggered. It's used for implementation of retractable stack.

retractEvent :: m (Event t ())

Get event that fires when any of input events in retract is triggered. It's used for implementation of retractable stack.

wipeRetractEvent :: m (Event t (Maybe Int))

Get event that fires when any of input events in wipeRetract is triggered. It's used for implementation of retractable stack.

getRetractStack :: m (Dynamic t [Retractable t m])

Get current stack of widget history

withRetractStack :: Dynamic t [Retractable t m] -> m a -> m a

Execute subcomputation with given widget history. Affects results of getRetractStack.

Instances

(PerformEvent t m, MonadHold t m, Adjustable t m, MonadFix m, MonadIO (Performable m)) => MonadRetract t (RetractT t m)

Defined in Reflex.Dom.Retractable.Trans.Internal

Methods

nextWidget :: Event t (Retractable t (RetractT t m)) -> RetractT t m (Event t ())

retract :: Event t () -> RetractT t m (Event t ())

wipeRetract :: Event t (Maybe Int) -> RetractT t m (Event t ())

nextWidgetEvent :: RetractT t m (Event t (Retractable t (RetractT t m)))

retractEvent :: RetractT t m (Event t ())

wipeRetractEvent :: RetractT t m (Event t (Maybe Int))

getRetractStack :: RetractT t m (Dynamic t [Retractable t (RetractT t m)])

withRetractStack :: Dynamic t [Retractable t (RetractT t m)] -> RetractT t m a -> RetractT t m a

MonadRetract t m => MonadRetract t (ReaderT r m)

Defined in Reflex.Dom.Retractable.Class

Methods

nextWidget :: Event t (Retractable t (ReaderT r m)) -> ReaderT r m (Event t ())

retract :: Event t () -> ReaderT r m (Event t ())

wipeRetract :: Event t (Maybe Int) -> ReaderT r m (Event t ())

nextWidgetEvent :: ReaderT r m (Event t (Retractable t (ReaderT r m)))

retractEvent :: ReaderT r m (Event t ())

wipeRetractEvent :: ReaderT r m (Event t (Maybe Int))

getRetractStack :: ReaderT r m (Dynamic t [Retractable t (ReaderT r m)])

withRetractStack :: Dynamic t [Retractable t (ReaderT r m)] -> ReaderT r m a -> ReaderT r m a

retractStack :: forall t m. MonadRetract t m => m () -> m (Event t ())

All body of the widget will be rerendered when some subcomputation emits switching event. Plug the function somewhere close to the root of your reflex frontend and use functions from MonadRetract class to control switching content of the widget.