How to remove a title from a tab in Shiny that gets carried on different pages?

Question

I'm building a form in Shiny. I'm using tabs to put information in different pages. In the code here, I'm having 3 main pages: 1. the main form to fill, 2. the "help" page 3. and the "thanks for submitting!".

The only thing is that when I submit the form, the title of one of the tab is sticking in place. I want to remove the title on one of the tab (see figures).

library(shiny)
library(shinydashboard)
# Fields definition -------------------------------------------------------
fields <- c("name", # the order here will be the same as the one that is saved in a CSV! 
            "title_reference",
            "year_publication",
            "first_author",
            "journal",
            "Species",
            "used_shiny",
            "favourite_pkg", 
            "os_type", 
            "r_num_years")

# Mandatory fields --------------------------------------------------------
fieldsMandatory <- c("name", 
                     "favourite_pkg")
# Labeling with star for mandatory fields
labelMandatory <- function(label) {
  tagList(
    label,
    span("*", class = "mandatory_star")
  )
}

# Design ------------------------------------------------------------------
appCSS <- 
  ".mandatory_star { color: red; }
#error { color: red; }"

# To save the Data  -------------------------------------------------------
library(rdrop2) 
# This  is a folder that is going to be created on Dropbox 
outputDir <- "responses"

epochTime <- function() {
  as.integer(Sys.time())
}

humanTime <- function() {
  format(Sys.time(), "%Y%m%d-%H%M%OS")
}

saveData <- function(data) {
  data = c(data, timestamp = epochTime())
  data <- t(data)
  # Create a unique file name
  fileName <- sprintf("evo_rates_form_%s_%s.csv", 
                      humanTime(), 
                      digest::digest(data))
  # Write the data to a temporary file locally
  filePath <- file.path(tempdir(), 
                        fileName)
  write.csv(data, 
            filePath, 
            row.names = FALSE, 
            quote = TRUE)

  # Upload the file to Dropbox
  drop_upload(filePath, 
              dest = outputDir)
}

loadData <- function() {
  # Read all the files into a list
  filesInfo <- drop_dir(outputDir)
  filePaths <- filesInfo$path
  data <- lapply(filePaths, drop_read_csv, stringsAsFactors = FALSE)
  # Concatenate all data together into one data.frame
  data <- do.call(rbind, data)
  data
}


# ShinyAPP ----------------------------------------------------------------
# Shiny app with 3 fields that the user can submit data for
shinyApp(
  ui = dashboardPage(skin = "green",
                     dashboardHeader(title = "Evolutionary Rates Data Collection", titleWidth = 350),
                     dashboardSidebar(#disable = TRUE,
                       width = 250,
                       sidebarMenu(menuItem("Menu Item"),
                                   menuItem("Form", tabName = "form_tab", icon = icon("file-text")),
                                   menuItem("Help", tabName = "help_tab", icon = icon("question"))
                       )
                     ),
                     dashboardBody(

                       shinyjs::useShinyjs(), 
                       shinyjs::inlineCSS(appCSS), # you need this if you want to change the "design" of you form
                       # titlePanel("Evolutionary Rates Form"),

                       # DataTables
                       DT::dataTableOutput("responses", # this will customize the table
                                           width = 300), 
                       # tags$hr(), # This is adding a horizontal rule (line)

                       # Form inputs -------------------------------------------------------------
                       tabItems(
                         # First tab content
                         tabItem(tabName = "form_tab",
                                 h2("Main form"),

                                 div(
                                   id = "form",
                                   ## text input 
                                   textInput("name", 
                                             labelMandatory("Name (First and last name)"), ""),
                                   textInput("favourite_pkg", 
                                             labelMandatory("Favourite R package")),
                                   textInput("title_reference",
                                             "Title of the reference"),
                                   textInput("year_publication",
                                             "Year of publication"),
                                   textInput("first_author",
                                             "First author"),
                                   textInput("journal",
                                             "Journal"),
                                   textInput("Species","Species"),

                                   ## Checkbox input 
                                   checkboxInput("used_shiny", 
                                                 "I've built a Shiny app in R before", 
                                                 FALSE),
                                   ## Slider input 
                                   sliderInput("r_num_years", 
                                               "Number of years using R",
                                               0, 25, 2, ticks = FALSE),

                                   ## Dropdown menu input 
                                   selectInput("os_type", 
                                               "Operating system used most frequently",
                                               c("",  "Windows", "Mac", "Linux")),

                                   ## Action button 
                                   actionButton("submit", 
                                                "Submit"),

                                   # Submission progression bar or Error
                                   shinyjs::hidden(
                                     span(id = "submit_msg", 
                                          "Submitting..."),
                                     div(id = "error",
                                         div(br(), 
                                             tags$b("Error: "), # b tags is for bold text 
                                             span(id = "error_msg"))
                                     ) # Closing div
                                   ) # Closing shinyjs::hidden

                                 ) # Closing div
                         ), # closing tab 1 

                         # Second tab content
                         tabItem(tabName = "help_tab",
                                 h2("Want some help or information?"))
                       ), # Closing tabItems

                       # Thank you message -------------------------------------------------------    
                       shinyjs::hidden(
                         div(
                           id = "thankyou_msg",
                           h2("Thanks, your response was submitted successfully!"),
                           actionLink("submit_another", 
                                      "Submit another response")
                         ) # Closing div 
                       ) # Closing shinyjs::hidden

                     ) # Closing DashboardBody
  ), # Closing DashboardPage

  # Server ------------------------------------------------------------------
  server = function(input, output, session) {

    # Whenever a field is filled, aggregate all from data
    formData <- reactive({
      data <- sapply(fields, function(x) input[[x]])
      data
    })

    observe({
      # check if all mandatory fields have a value
      mandatoryFilled <-
        vapply(fieldsMandatory,
               function(x) {
                 !is.null(input[[x]]) && input[[x]] != ""
               },
               logical(1))
      mandatoryFilled <- all(mandatoryFilled)

      # enable/disable the submit button
      shinyjs::toggleState(id = "submit", 
                           condition = mandatoryFilled)
    })

    # When the Submit button is clicked, save the form data (action to take when submit button is pressed)
    observeEvent(input$submit, {
      shinyjs::disable("submit")
      shinyjs::show("submit_msg")
      shinyjs::hide("error")

      tryCatch({
        saveData(formData())
        shinyjs::reset("form")
        shinyjs::hide("form")
        shinyjs::show("thankyou_msg")
      },
      error = function(err) {
        shinyjs::text("error_msg", err$message)
        shinyjs::show(id = "error", anim = TRUE, animType = "fade")
      },
      finally = {
        shinyjs::enable("submit")
        shinyjs::hide("submit_msg")
      })
    })

    # Hide the thank you message and show the form 
    observeEvent(input$submit_another, {
      shinyjs::show("form")
      shinyjs::hide("thankyou_msg")
    })    

  }
)

Answer 1

If I am reading this correctly, the issue is that you never tell your app to hide it. In the ui, you have:

 tabItem(tabName = "form_tab",
    h2("Main form"),
     div(
       id = "form",
       #### A bunch more stuff)

so, the h2("Main form") is not part of the div with id="form".

In the server you have

observeEvent(input$submit, {
  shinyjs::disable("submit")
  shinyjs::show("submit_msg")
  shinyjs::hide("error")

  tryCatch({
    saveData(formData())
    shinyjs::reset("form")
    shinyjs::hide("form")
    shinyjs::show("thankyou_msg")
  }, #### More stuff

Which will hide "form" in the ui but that does not include the h2("Main form") so that stays visible. If you move that into the "form" div that should fix it.