r - Add dynamic tabs in shiny dashboard using conditional panel

Question

I would like to have dynamic tabs for my shiny app. I tried the below code

## app.R ##
library(shiny)
library(shinydashboard)

ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(
    checkboxGroupInput("Tabs", 
                       label = h4("tabpanel"), 
                       choices = list("tabs" = "tabs"),
                       selected = NULL),
    checkboxGroupInput("moreTabs", 
                       label = h4("moretabpanel"), 
                       choices = list("moretabs" = "moretabs"),
                       selected = NULL)
  ),
  dashboardBody(
    conditionalPanel(
      condition = "input.Tabs == 'tabs'",
      tabBox(
        title = "intro",
        id= "ttabs", width = 8, height = "420px",
        tabPanel("Files", dataTableOutput("Files")),
        conditionalPanel(
          condition = "input.moreTabs == 'moretabs'",
          tabPanel("Files1", dataTableOutput("Files1"))
        )
  )
)
)
)
server <- function(input, output) { }

shinyApp(ui, server)

However, I am not successful to use the tab panel dynamically. It shows only one tab, and on checking, its supposed to show the second tab.

Answer 1

You can dynamically create the ui as per example below.

Example 1: Using RenderUI

rm(list = ls())
library(shiny)
library(shinydashboard)

ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(
    checkboxGroupInput("Tabs", label = h4("tabpanel"), choices = list("tabs" = "tabs"),selected = NULL),
    checkboxGroupInput("MoreTabs", label = h4("moretabpanel"), choices = list("moretabs" = "moretabs"),selected = NULL)
  ),
  dashboardBody(
    uiOutput("ui")
  )
)
server <- function(input, output) { 

  output$ui <- renderUI({

    check1 <- input$Tabs == "tabs"
    check2 <- input$MoreTabs == "moretabs"

    if(length(check1)==0){check1 <- F}
    if(length(check2)==0){check2 <- F}

    if(check1 && check2){
      tabBox(title = "intro",id= "ttabs", width = 8, height = "420px",
             tabPanel("Files", dataTableOutput("Files")),
             tabPanel("Files1", dataTableOutput("Files1"))
      )
    }
    else if(check1){
      tabBox(title = "intro",id= "ttabs", width = 8, height = "420px",tabPanel("Files", dataTableOutput("Files")))
    }
    else{return(NULL)}
  })
}

shinyApp(ui, server)

Example 2: Using conditionalPanel

rm(list = ls())
library(shiny)
library(shinydashboard)

ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(
    checkboxGroupInput("Tabs", label = h4("tabpanel"), choices = list("tabs" = "tabs"),selected = NULL),
    checkboxGroupInput("MoreTabs", label = h4("moretabpanel"), choices = list("moretabs" = "moretabs"),selected = NULL)
  ),
  dashboardBody(

    conditionalPanel(
      condition = "input.MoreTabs == 'moretabs' && input.Tabs == 'tabs'",
      tabBox(
        title = "intro",
        id= "ttabs", width = 8, height = "420px",
        tabPanel("Files",value=1, dataTableOutput("Filesa")),
        tabPanel("Files1",value=2, dataTableOutput("Files1a"))
      )
    ),

    conditionalPanel(
      condition = "input.Tabs == 'tabs' && input.MoreTabs != 'moretabs'",
      tabBox(
        title = "intro",
        id= "ttabs", width = 8, height = "420px",
        tabPanel("Files",value=3, dataTableOutput("Files"))
      ))  
))
server <- function(input, output) { }
shinyApp(ui, server)