Shiny how to block the user from accessing a tab?-CodePudding

I need to block the user from accessing to other tabs until certain actions are fulfilled. In this reproducible example, I want to block the user to access the Tab 2 until he pressed the button.

This is how the app looks:

Here's the code for the app:

library(shiny)

ui <- shinyUI(navbarPage("",
                         tabPanel(h1("Tab1"), value = "nav1",
                                  mainPanel(
                                            br(),
                                            h2("The user must press this button to access the other tab."),
                                            br(),
                                            shiny::actionButton('button', 'press the button')
                                  )
                         ),
                         tabPanel(h1("Tab2"),
                                  value = "nav2",

                                  h3('Block access until user presses button')
                         )
)
)

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


})

# Run the application
shinyApp(ui = ui, server = server)

I would like the user to be able to see that Tab2 exists, but make it unclickable until they press the button.

Any ideas?

CodePudding user response：

Adding detail to my comment above:

library(shiny)

ui <- shinyUI(navbarPage("",
        tabPanel(
          h1("Tab1"), 
          value = "nav1",
          mainPanel(
            br(),
            h2("The user must press this button to access the other tab."),
            br(),
            shiny::actionButton('button', 'press the button')
          )
        ),
        tabPanel(
          h1("Tab2"),
          value = "nav2",
          uiOutput("tab2contents")
        )
      )
    )    

server <- shinyServer(function(input, output) {
   v <- reactiveValues(tab2Active=FALSE)
   
  observeEvent(input$button, { v$tab2Active <- TRUE})

  output$tab2contents <- renderUI({
    if (v$tab2Active) {
      h3('Tab 2 is active')
    } else {
      h3('Block access until user presses button')
    }
  })
})

# Run the application
shinyApp(ui = ui, server = server)

CodePudding user response：

Use conditionalPanel(). Condition? The button shouldn't have zero clicks.

Your example now becomes:

library(shiny)

ui <- shinyUI(
  navbarPage(
    title = "", 
    
    tabPanel(
      title = h1("Tab1"), 
      value = "nav1",
      
      mainPanel(
        br(),
        h2("The user must press this button to access the other tab."),
        br(),
        shiny::actionButton('button', 'press the button')
      )
    ), 
    
    tabPanel(
      h1("Tab2"),
      value = "nav2",
      
      # ----conditional panel here----
      conditionalPanel(
        condition = "input.button != 0", 
        
        h3('Block access until user presses button')
      )
    )
  )
)

server <- shinyServer(function(input, output) {
  
  
})

# Run the application
shinyApp(ui = ui, server = server)