shiny:renderUI and shiny:uioutput to produce a new menuItem and a new output, but the tabItem not showing

Question

I want to create a new menuItem and a new plotOutput based on an actionButton, and the newly rendered plotOutput will display a plot based on the submitted value. I have successfully generated the menuItem and the numericInput widget with submitted value, but the plot and the corresponding tabItem is not showing.
Here is the workflow:

submit -> render a menuItem with a input object and a plotOutput -> the plotOutput will be display based on the rendered input object

The second procedure is successful but the rest of that is not working, the code is listed below:

library(shiny)
library(shinydashboard)

## ============================================ Define ui ==================================================

header1 <- dashboardHeader(
  title = "My Dynamic Menu"
) #dashboardHeader

# DYNAMIC UI
sidebar1 <- dashboardSidebar(
  sidebarMenu(
    menuItem('aa',tabName = 'aa')
  ) ,
  sidebarMenuOutput('bb')
) #dashboardSidebar
#
body1 <- dashboardBody(
  tabItems(
    tabItem(tabName = 'aa',
            numericInput('num_input', 'number', value = 5), 
            actionButton('submit','Submit')),
    tabItem(tabName = "main", uiOutput('eee')) # put a tabItem here
  ) #tabItems
) #dashboardBody

ui <- dashboardPage(header1, sidebar1, body1)

server <- function(input, output, session) {
  dt<-eventReactive(input$submit, {
    input$num_input * 5
  })
  
  observeEvent(input$submit, {
    output$bb<-renderMenu({
      sidebarMenu(
        menuItem("Main", tabName = "main", 
                 numericInput('ddd', 'input value', value = dt()),
                 numericInput('ggg', 'another input', value=dt()+5))
      )
    })
    
    output$eee<-renderUI({
      fluidRow(
        p('hello'),
        plotOutput('fff')
      )
    })
  })
  
  
   observeEvent({
     input$ddd
     input$ggg
   },{
       output$fff<-renderPlot({
       plot(1:input$ddd, main=as.character(input$ggg))
     })
   })
  
} #server
## ============================================ Run application ============================================
shinyApp(ui, server)

Many thanks if this issue is addressed.

Answer 1

to be linked with a tabItem, menuItem should only contain menuSubItem. If you remove your two numeric inputs (ddd and ggg) then the main page is activated when you click on the newly created main menuitem. Mixing navigation and inputs is not a good idea.

You'd better move you inputs to your main tabItem or put them in a separate panel (not in the menu) in the sidebar.

added a uiOutput for inputs in ui

# DYNAMIC UI
sidebar1 <- dashboardSidebar(
  sidebarMenu(
    menuItem('aa',tabName = 'aa')
  ) ,
  sidebarMenuOutput('bb'),
  uiOutput("inputs")
) #dashboardSidebar

added a renderUI for this output in server

output$inputs <- renderUI(tagList(
      numericInput('ddd', 'input value', value = dt()),
      numericInput('ggg', 'another input', value=dt()+5)
    ))

and removed inputs from your renderMenu

output$bb<-renderMenu({
      message("bb")
      sidebarMenu(
        menuItem("Main", tabName = "main")
      )
    })

You have to navigate manually to the main page though to display the plot