Reflex.Widget.Basic

Documentation

sortableList

Arguments

:: (MonadHold t m, MonadFix m, Adjustable t m, Ord k)

=> (k -> v -> m a)

Function to render the content for each key/value pair

-> Map k v

The sortable list with an initial ordering determined by the Map keys in ascending order

-> Event t (v -> v -> Ordering)

An event carrying a sort function for the list

-> m (Map k a)

Build sortable content in such a way that re-sorting it can cause minimal disruption to an existing context.

Naively re-sorting a list of images would destroy every image and add them back in the new order. This framework is able to avoid that by preserving the identity of each image and simply moving it to the new location.

Example:

let sortByFst = buttonA $> comparing fst
    sortBySnd = buttonB $> comparing snd
    sortEvent = leftmost [sortByFst, sortBySnd]
sortableList
  (\k v -> text $ "\n" ++ show k ++ " " ++ v)  -- show each element on a new line
  (Map.fromList $ zip [0..] [(3, "a"), (2, "b"), (1, "c")])
  sortEvent