Adding a bslib::nav_panel in Shiny modules

Question

I am trying to add a bslib::nav_panel as part of a Shiny module, but I am struggling to make this happen. See a minimal reproducible example below:

library(shiny); library(bslib); library(shinyWidgets)

login_ui <- function(id) {
  ns <- NS(id)
  tagList(
         actionBttn(inputId = ns("add_tab"), label = "Add", style = "pill", color = "danger")
  )
}
login_server <- function(id) {
  moduleServer(
    id,
    function(input, output, session) {
      ns = session$ns
      observeEvent(input$add_tab, {
      nav_insert(id="nav_tab", nav=nav_panel("This is a new tab"))
      })
    })
}

#load libraries
ui <- page_fluid(
  navset_tab(id = "nav_tab", nav_panel("Add a new tab", login_ui("add_test"))))

server <- function(input, output) {
  login_server("add_test")
}

shinyApp(ui = ui, server = server)

Any advice would be appreciated.

Answer 1

The issue is that nav_insert will (try to) insert a nav panel in a navset_tab with id="nav_tab" in the module's namespace:

Instead, to insert the panel in the navset_tab created in your main app you could pass main app's session object to your module which could then be passed to the session= argument of nav_insert:

library(shiny)
library(bslib)
library(shinyWidgets)

login_ui <- function(id) {
  ns <- NS(id)
  tagList(
    actionBttn(
      inputId = ns("add_tab"),
      label = "Add",
      style = "pill",
      color = "danger"
    )
  )
}

login_server <- function(id, parent_session) {
  moduleServer(
    id,
    function(input, output, session) {
      observeEvent(input$add_tab, {
        nav_insert(
          id = "nav_tab",
          nav = nav_panel("This is a new tab"),
          session = parent_session
        )
      })
    }
  )
}

# load libraries
ui <- page_fluid(
  navset_tab(
    id = "nav_tab",
    nav_panel(
      "Add a new tab",
      login_ui("add_test")
    )
  )
)

server <- function(input, output, session) {
  login_server("add_test", session)
}

shinyApp(ui = ui, server = server)