zapnito / elm-waypoints

waypoints effect manager for Elm

elm-waypoints

Waypoints effect manager for Elm

Waypoints are elements on your page that you want to know about when they enter the browser's view. Some scenarios where this might be useful:

1. Tracking when a user has read a message, i.e. a messages is assumed "read" once the message is in view - see https://github.com/zapnito/elm-waypoints/tree/master/examples/MentionsTracker.elm

2. Infinite loading - Detect when user is scrolled to the bottom and load more results

Install

As this is an effect manager and uses native code it isn't available at http://package.elm-lang.org. Instead you'll need to use https://github.com/gdotdesign/elm-github-install. Just add "zapnito/elm-waypoints": "0.2.0 <= v < 1.0.0" to your elm-package.json as usual then run $ elm-github-install.

Usage

type Msg =
    WaypointTriggered String

update msg model =
    case msg of
        WaypointTriggered message ->
            ...

subscriptions : Model -> Sub Msg
subscriptions model =
    Sub.batch
        [ Waypoints.enteredView "element1" (WaypointTriggered "element entered window")
        ]


view : Model -> Html Msg
view model =
    div [ id "element1" ][ text "My waypoint" ]

See https://github.com/zapnito/elm-waypoints/tree/master/examples for a working example.