Create Navigation Buttons for Survey Pages

This function creates both 'Previous' and 'Next' buttons for navigating between pages in a surveydown survey. The buttons are positioned on the left (Previous) and right (Next) of the page. The Previous button allows users to return to previously visited pages, while the Next button maintains the standard forward navigation behavior.

Usage

sd_nav(
  page_next = NULL,
  label_previous = NULL,
  label_next = NULL,
  show_previous = NULL,
  show_next = TRUE
)

Arguments

page_next: Character string. The ID of the next page to navigate to when the Next button is clicked. If NULL, the survey will navigate to the default next page in sequence.
label_previous: Character string. The label for the 'Previous' button. Defaults to NULL, which uses "← Previous" (or the translated equivalent).
label_next: Character string. The label for the 'Next' button. Defaults to NULL, which uses "Next →" (or the translated equivalent).
show_previous: Logical. Whether to show the Previous button. Set to FALSE for the first page where there is no previous page to navigate to. If NULL (default), uses the show-previous setting from YAML or sd_server().
show_next: Logical. Whether to show the Next button. Set to FALSE to hide the Next button. Defaults to TRUE.

Value

A 'shiny' tagList containing the navigation buttons UI elements.

Details

The function generates two 'shiny' action buttons:

Previous button: Positioned on the left, navigates to the last visited page. Uses page history tracking to determine the previous page.
Next button: Positioned on the right, navigates forward. Can be activated by clicking or pressing the Enter key when visible.

The buttons are styled to appear on opposite sides of the page using flexbox layout, and include arrow symbols to indicate direction.

Examples

if (interactive()) {
  library(surveydown)

  # Basic usage with both buttons
  sd_nav()

  # First page - hide Previous button
  sd_nav(show_previous = FALSE)

  # Last page - hide Next button
  sd_nav(show_next = FALSE)

  # Hide both navigation buttons
  sd_nav(show_previous = FALSE, show_next = FALSE)

  # Custom labels
  sd_nav(
    label_previous = "Go Back",
    label_next = "Continue"
  )

  # Specify next page explicitly
  sd_nav(page_next = "demographics")
}