Different behavior of the conditionalPanel, depending on the method of creation

Hi!
I'm trying to develop an app with dynamically creating of tabsetPanel where different plots should be visualized depending on user's choice. When I create conditionalPanel statically it works great. But if I create conditionalPanel dynamically something is going wrong - not only plots are not displayed but even all conditionalPanels disappearing.

Not interesting, but needed code:

library(shiny)
library(shinydashboard)
library(ggplot2)
library(dplyr)
library(htmlwidgets)
library(rlist)

data("midwest", package = "ggplot2")
midwest <- midwest %>% 
  select(state, category, percprof, area, poptotal, county)
midwest <- midwest %>% 
  filter(category %in% c("AAR", "LHR", "ALU", "LAR", "HAU"))
categories <- unique(midwest$category)
states <- unique(midwest$state)
max_perc_prof <- max(midwest$percprof)

header <- dashboardHeader(title = "Midwest analysis")

sidebar <- dashboardSidebar(
  sidebarMenu(
    menuItem(text = "Analysis", tabName = "dcTab", icon = icon("bar-chart-o"))
  )
)

Here is body code with example of perfectly working conditional panel

body <- dashboardBody(
  tabItems(
    tabItem(tabName = "dcTab",
      fluidRow(
        box(width = 12, 
          numericInput(inputId = "min_perc_prof", 
                       label = "Minimum percent profession:",
                       min = 0,
                       max = max_perc_prof,
                       value = 2,
                       step = 1
          )
        ),
        conditionalPanel(condition = paste0("input.min_perc_prof", " >= ", 2), 
                         h4("I'm good conditionalPanel"),
                         box(width = 12, background = "blue", height = 300
                             # HERE is NOT a problem with plot     
                            , plotOutput("plt_1", height = 280)
                         )
        )
      ),
      fluidRow(
        uiOutput(outputId = "dynamicContentUI")
      )
    )
  )
)

ui <- dashboardPage(header = header,
                    sidebar = sidebar,
                    body = body
)

And here is a code on server side:

server <- function(input, output, session) {

  database <- reactive({
    req(input$min_perc_prof)
    midwest %>% 
      filter(percprof >= input$min_perc_prof)
  })

  tab_state_names <- reactive({
    unique(database()$state)
  })

tab_category_names <- reactive({
    res <- list()
    for(i in seq(tab_state_names())){
      current_state <- tab_state_names()[[i]]
      current_data <- database() %>% filter(state == current_state)
      current_categories <- sort(unique(current_data$category))
      res[[ current_state ]] <- current_categories
    }
    res
  })

 # Init Ggplot
  p1 <- ggplot(midwest, aes(x=area, y=poptotal)) + geom_point()

  output$plt_1 <- renderPlot({
    p1
  })

tab_category_content <- reactive({
    if (is.null(tab_category_names())) return(NULL)

    res_content <- lapply(seq(tab_state_names()), function(current_state){

      if(current_state <= length(tab_category_names())){

        tabnames <- tab_category_names()[[ current_state ]]

        res <- lapply(seq(tabnames), function(current_category){ 

          result_list <- list()

          selInputId <- paste0("county_", current_state, "_", current_category)

          current_data <- database() %>% 
                          filter(state == tab_state_names()[[current_state]]) %>% 
                          filter(category == tab_category_names()[[current_state]][[current_category]])

          county_names <- unique(current_data$county)

          sel_input <- selectInput(inputId = selInputId, 
                                label = "Choose county",
                                choices = county_names
          )

          result_list <- c(result_list, list(sel_input))

          for (current_county in county_names) {

            plot_list <- list()

            current_panel <- conditionalPanel(condition = paste0("input.", selInputId, " === ", "\"", current_county, "\""),
                                              h5(current_county),
                                              box(width = 12, background = "blue", height = 300,
                                                  title = current_county
                                               # HERE is a problem with plot     
                                              #  , plotOutput("plt_1")
                                              )

            )
            result_list <- c(result_list, list(current_panel))
          }
          result_list
        })
        res
      }
    })
    names(res_content) <- tab_state_names()

    res_content
  })

  tab_state_content <- reactive({

    if (is.null(tab_state_names())) return(NULL)

    lapply(tab_state_names(), function(current_state){

      if(!is.null(tab_category_names()[[ current_state ]])){

        tabs <- lapply(seq(tab_category_names()[[ current_state ]]), function(current_category) {
          tabPanel(tab_category_names()[[current_state]][[ current_category ]], tab_category_content()[[current_state]][[ current_category ]])
        })
        args = c(tabs, list(width = 12, id = paste0("tab_cat_in_state_", current_state)))

        do.call(tabBox, args)
      }

    })
  })

  output$dynamicContentUI <- renderUI({
    tabs <- lapply(seq(tab_state_content()), function(current_state) {
      tabPanel(tab_state_names()[[ current_state ]], tab_state_content()[[ current_state ]])
    })
    do.call(tabsetPanel, tabs)
  })

}

shinyApp(ui = ui, server = server)

I create a tabsetPanel with dynamic number of tabs. Each of them contains tabBox with dynamic number of tabs. Each of them contains a set of conditionalPanels with condition defined by user choice. Every conditionalPanel should contain a plot and this is an essence of the problem.

A code

current_panel <- conditionalPanel(condition = paste0("input.", selInputId, " === ", "\"", current_county, "\""),
   h5(current_county),
   box(width = 12, background = "blue", height = 300,
      title = current_county
      # HERE is a problem with plot     
      #  , plotOutput("plt_1")
   )
)

works great - we can see conditionalPanel with empty blue box. But the same code with plotOutput

current_panel <- conditionalPanel(condition = paste0("input.", selInputId, " === ", "\"", current_county, "\""),
   h5(current_county),
   box(width = 12,
      background = "blue", height = 300,
      title = current_county
      # HERE is a problem with plot     
      , plotOutput("plt_1")
   )
)

has totally wrong result. Because not only plot isn't visible but also blue box and conditional panel are disappearing.

I generally do not understand what I need to change. Any advice will be very useful.

The reason that the plots aren't showing is because you have multiple plotOutputs with the same ID, plt_1. With Shiny, you can only have one output with a given ID.

When Shiny detects that there are multiple outputs with the same name, it prints this in the browser's Javascript console:


This is a Javascript error. When it happens, it stops other Javascript code from running, and this will prevent some of Shiny's Javascript code from running, including the part that decides whether or not to display conditionalPanels.