Todo list app in Fabulous.XamarinForms

TodoList.fs

namespace TodoList

module App =
    type Todo =
        { Task: string }

    type Model =
        { Todos: Todo list
          EntryText: string }

    type Msg =
        | AddTodoFromEntryText
        | RemoveTodo of Todo
        | EntryTextChanged of string

    let init () =
        { Todos = []; EntryText = "" }

    let update msg model =
        match msg with
        | AddTodoFromEntryText ->
            let newTodo = { Task = model.EntryText }
            { model with Todos = newTodo :: model.Todos; EntryText = "" }

        | RemoveTodo todo ->
            let filteredTodos = model.Todos |> List.filter (fun t -> t <> todo)
            { model with Todos = filteredTodos }

        | EntryTextChanged newText ->
            { model with EntryText = newText }

    let view model dispatch =
        View.ContentPage(
            View.StackLayout(
                padding = (
                    if Device.RuntimePlatform = Device.iOS then
                        Thickness(20., 40., 20., 20.)
                    else
                        Thickness(20., 0.)
                ),
                children = [
                    // Title
                    View.Label(
                        text = "My To-Do list",
                        fontSize = FontSize.fromNamedSize NamedSize.Title,
                        horizontalOptions = LayoutOptions.Center
                    )

                    // Add new todo
                    View.Grid(
                        coldefs = [ Star; Auto ],
                        children = [
                            View.Entry(
                                text = model.EntryText,
                                textChanged = fun e -> dispatch (EntryTextChanged e.NewTextValue)
                            )

                            View.Button(
                                text = "Add todo",
                                command = fun () -> dispatch AddTodoFromEntryText)
                            ).Column(1)
                        ]
                    )

                    // Todo list
                    View.ListView([
                        for todo in List.rev model.Todos ->
                            View.TextCell(
                                text = todo.Task,
                                contextActions = [
                                    View.MenuItem(
                                        text = "Complete",
                                        command = fun () -> dispatch (RemoveTodo todo)
                                    )
                                ]
                            )
                    ])
                ]
            )
        )

    let program = XamarinFormsProgram.mkSimple init update view

type App() as app =
    inherit Xamarin.Forms.Application()

    let runner =
        App.program
        |> Program.withConsoleTrace
        |> XamarinFormsProgram.run app

#if DEBUG
    do runner.EnableLiveUpdate()
#endif