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Update a Govstyle radio button input on the client

Source: R/radio_button_input.R
update_radio_button_Input.Rd

Server-side companion to radio_button_Input(), mirroring shiny::updateRadioButtons(). Use it to change the selected option, the available choices, or the label of an existing radio button group from within an observer, for example to keep a cookies settings radio in sync with a choice the user made elsewhere.

Usage

update_radio_button_Input(
  session = shiny::getDefaultReactiveDomain(),
  inputId,
  label = NULL,
  choices = NULL,
  selected = NULL,
  inline = FALSE,
  small = FALSE,
  choiceNames = NULL,
  choiceValues = NULL
)

Arguments

session

The session object passed to the Shiny server function. Defaults to the current reactive domain.

inputId

The id of the radio_button_Input() to update

label

New label for the input, or NULL to leave unchanged

choices

New vector of choices, or NULL to leave unchanged (if elements of the vector are named then that name rather than the value is displayed to the user)

selected

The value to select, or NULL to leave unchanged

inline

Whether the radios are inline. Only applies when choices (or choiceNames/choiceValues) are also supplied, since regenerating the options replaces the whole option container; if you do not re-pass it the layout falls back to default. Defaults to FALSE

small

Whether to use the smaller radios. Only applies when choices (or choiceNames/choiceValues) are also supplied, since regenerating the options replaces the whole option container; if you do not re-pass it the layout falls back to default. Defaults to FALSE

choiceNames, choiceValues

As in radio_button_Input(), an alternative to choices allowing richer labels. Both must be supplied together

Value

Called for its side effect of sending a message to the client; no return value

Details

Only the arguments you supply are sent to the client; everything left at its default of NULL is left untouched. Because it relies on session$sendInputMessage(), the inputId is namespaced automatically when called inside a Shiny module, so pass the unnamespaced id just as you would to shiny::updateRadioButtons().

This function is deliberately agnostic about why you are updating the radio, which makes it a useful building block for packages that layer extra behaviour (such as analytics cookie consent) on top of shinyGovstyle. See the cookies and analytics vignette for an example of extending it.

See also

radio_button_Input()

Other Govstyle select inputs: button_Input(), checkbox_Input(), file_Input(), radio_button_Input(), select_Input()

Examples

ui <- shiny::fluidPage(
  shinyjs::useShinyjs(),
  shinyGovstyle::radio_button_Input(
    inputId = "cookies",
    label = "Do you want to accept analytics cookies?",
    choices = c("Yes" = "yes", "No" = "no"),
    selected = "no",
    inline = TRUE
  ),
  shinyGovstyle::button_Input(inputId = "accept", label = "Accept cookies")
)

server <- function(input, output, session) {
  # Keep the radio in sync with a choice made elsewhere
  shiny::observeEvent(input$accept, {
    shinyGovstyle::update_radio_button_Input(
      session,
      inputId = "cookies",
      selected = "yes"
    )
  })
}
if (interactive()) shinyApp(ui = ui, server = server)