in R shiny, how to automatically or based on function tabPanel, given we have 3 levels of lists?

Question

I need to create conditional 3 levels of tabs the first level or tabPanel includes three tabs \"NUTS\",\"SWEETS\",\"DRINKS\" so the

level1<-list(DRINKS,SW

Answer 1

hotdrinks<-list("tea","green tea") 
juices<-list("orange","mango") 
energydrinks<-list("powerhorse","redbull") 
drinks<-list("hotdrinks"=hotdrinks, "juices"=juices, "energydrinks"=energydrinks) 

lst_drinks <- lapply(seq_along(drinks), 
                     #browser()
                     #create 2nd level, tab name with the corresponding 3rd level list  
                     function(x) tabPanel(names(drinks[x]),
                                          #create tabsetPanel for hdrinks, jcs, ngdrinks level i.e. 3rd level 
                                          do.call("tabsetPanel", 
                                                  lapply(drinks[[x]], function(y) tabPanel(y))
                                                  )
                                          )
                     )

hdrinks<-  
  tabsetPanel(
    tabPanel("tea"),
    tabPanel("green tea")
  )
jcs<-  
  tabsetPanel(
    tabPanel("orange"),
    tabPanel("mango")
  )
ngdrinks<-  
  tabsetPanel(
    tabPanel("powerhorse"),
    tabPanel("redbull")
  )

runApp(list(
  ui = shinyUI(fluidPage(
    sidebarLayout( 
      sidebarPanel(width = 2),      
      mainPanel(tabsetPanel(id='conditioned',
                            tabPanel("drinks",value=3,
                                     tabsetPanel(
                                       tabPanel("hotdrinks",
                                                #No need for tabsetPanel as hdrinks already has one, therefore I removed it in lapply
                                                tabsetPanel(hdrinks)),
                                       tabPanel("juices",
                                                tabsetPanel(jcs)),
                                       tabPanel("energydrinks",
                                                tabsetPanel(ngdrinks))

                                     )),
                            tabPanel("drinks-test",
                                     do.call("tabsetPanel", lst_drinks))
                                     ))
    ))),

  server = function(input, output, session) {}
))

The Full solution

hotdrinks<-list("tea","green tea") 
juices<-list("orange","mango") 
energydrinks<-list("powerhorse","redbull") 
drinks<-list("hotdrinks"=hotdrinks,"juices"=juices,"energydrinks"=energydrinks) 

biscuits<-list("loacker","tuc") 
choc<-list("aftereight","lindt") 
gum<-list("trident","clortes") 
sweets<-list("gum"=gum,"biscuits"=biscuits,"choc"=choc)

all <- list("drinks"=drinks, "sweets"=sweets)

all_lst <- lapply(seq_along(all), function(z) tabPanel(names(all)[z], 
                                                       do.call("tabsetPanel", 
                                                               lapply(seq_along(all[[z]]), function(x) tabPanel(names(all[[z]][x]), 
                                                                                                                do.call("tabsetPanel", 
                                                                                                                        lapply(all[[z]][[x]], function(y) tabPanel(y, DT::dataTableOutput(y)))
                                                                                                                        )
                                                                                                                )
                                                                      )
                                                               )
                                                       )
                  )

runApp(list(
  ui = shinyUI(fluidPage( 
    sidebarLayout( 
      sidebarPanel(width = 2),      
      mainPanel(do.call("tabsetPanel", c(id='conditioned', all_lst)))
      ))),
  server = function(input, output, session) {
    observe({
      nms = unlist(all)
      names(nms) <- sub('\\d', '', names(nms))
      for(i in seq_along(nms)){
        #browser()
        local({
          nm      = nms[i]
          CAT_var = unlist(strsplit(names(nm), '\\.'))[1]
          PN_var  = unlist(strsplit(names(nm), '\\.'))[2]
          SP_var  = nm[[1]]
          output[[SP_var]] <- DT::renderDataTable({filter(t1, CAT==CAT_var, PN==PN_var, SP==SP_var)})
        })
      }
    })
  }
))