Conditional @render.download button in shiny express

[isthisthat]

Hello, is there a way to condition (or @render.ui) a @render.download button in shiny express? My specific use-case is if a row is selected in a DataGrid, show the download button. Thanks!

[wch]

You can use render.express, which is similar to using render.ui, except where render.ui requires the function to return the UI components, render.express allows you to write code with Express syntax, where the UI components are automatically captured from evaluating the code.

Live example

from pathlib import Path
from shiny.express import ui, render, expressify, input

ui.input_select("show_hide", "Show or hide download", {"hide": "Hide", "show": "Show"})


@render.express
def download_ui():
    if input.show_hide() == "show":

        @render.download()
        def download1():
            path = Path(__file__).parent / "mtcars.csv"
            return str(path)

[isthisthat]

Wow that worked beautifully! Thanks @wch!