Elm Transit

Styled transitions with minimal boilerplate, typically for page transitions in single page apps:

exit (float from 0 to 1) -> your action -> enter (float from 0 to 1)

Uses elm-animations and Effects.tick for animation logic.

Usage

(Full working example here)

Extend WithTransition record type with your own model.

import Transit

type Page = Page1 | Page2

type alias Model = Transit.WithTransition { page: Page }

(Note: you're not bound to root model, you can also use it for sub-pages or components transitions)

Then wrap Action in one of your action types and call init and update in your update function.

Note that here we have a kind of recursive type definition, as Transit.Action with eventually trigger one Action.

type Action = NavigateTo Page | SetPage Page | TransitAction (Transit.Action Action)

update : Action -> Model -> (Model, Effects Action)
update action model =
  case action of

    NavigateTo page ->
      let
        timeline = Transit.timeline 100 (SetPage page) 200
        -- 100ms from 0 to 1, then action, then 200ms from 0 to 1
      in
        Transit.init TransitAction timeline model

    TransitAction a ->
      Transit.update TransitAction a model
        
    SetPage page ->
      ({ model | page = page }, Effects.none)

You can then use one of the provided functions in Transit.Style (or create one of your own) to add the visual effect in your view:

  div [ class "content", style (Transit.fadeSlideLeft 50 model) ] [ text "Some content" ]

Credits

• Thanks Alex Galays for the challenge
• Built with elm-animations, check it out!