When dashboard is present inside action-button it is showing result when button is pressed twice

[kartik]

In my code when i press load scenario button it is showing the dashboard page when load scenario button is pressed twice.I want my dashboard to appear in a single click.Can anyone help.Here is my code

 library("shiny")
 library("shinydashboard")
 ui <- fluidPage(


  actionButton("create_scenario", "Create Scenario"),
  actionButton("load_scenario","load scenario"),
 uiOutput("input"),
  uiOutput("inputs")
 )

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

  observeEvent(input$create_scenario,{

    output$input <- renderUI({
     textInput("txtInput","Enter Scenario Name","Enter name as scenario         
              (number of senario created +1)")
    })


   })

  observeEvent(input$load_scenario,{

    output$inputs <- renderUI({
     # textInput("txtInput","Enter Scenario Name","Enter name as scenario  
     #(number of senario created +1)")
      dashboardPage(
       dashboardHeader(title = "Basic dashboard"),
       dashboardSidebar(),
      dashboardBody(
      # Boxes need to be put in a row (or column)
      fluidRow(
        box(plotOutput("plot1", height = 250)),
        
        box(
          title = "Controls",
          sliderInput("slider", "Number of observations:", 1, 100, 50)
        ))))
 
  
} )

histdata <- rnorm(500)
output$plot1 <- renderPlot({
  data <- histdata[seq_len(input$slider)]
  hist(data)
    })


  })
}
shinyApp(ui, server)

Please ignore the create scenario button.One more help which is off topic can i add some colour to dashboard as it is not very attractive.

[barret]

I believe the issue is trying to put a dashboardPage() as an internal UI output. If I trim it down to just dashboardBody(), the code works as expected.

If you'd like all three parts, I would use three independent renderUI() methods. One for the header, sidebar, and body.

Updated app:

library("shiny")
library("shinydashboard")

ui <- fluidPage(
  actionButton("create_scenario", "Create Scenario"),
  actionButton("load_scenario","load scenario"),
  uiOutput("input"),
  uiOutput("inputs")
)

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

  state <- reactiveVal("none")
  observeEvent(input$create_scenario,{
    state("create")
  })
  observeEvent(input$load_scenario,{
    state("load")
  })


  output$inputs <- renderUI({
    req(state())

    state_val <- state()
    if (state_val == "create") {
      textInput("txtInput","Enter Scenario Name","Enter name as scenario
               (number of senario created +1)")
    } else if (state_val == "load") {
      # dashboardPage(
      #   dashboardHeader(title = "Basic dashboard"),
      #   dashboardSidebar(),
        dashboardBody(
          # Boxes need to be put in a row (or column)
          fluidRow(
            box(plotOutput("plot1", height = 250)),
            box(
              title = "Controls",
              sliderInput("slider", "Number of observations:", 1, 100, 50)
            )
          )
        )
      # )
    } else {
      NULL
    }
  })



  histdata <- rnorm(500)
  output$plot1 <- renderPlot({
    req(input$slider)
    data <- histdata[seq_len(input$slider)]
    hist(data)
  })

}
shinyApp(ui, server)

---

Side reactivity goal: try to keep render* statements outside of observe* executions. Instead, in observe* methods set data values that can be read inside render* methods.

The example above uses state() to determine what is displayed in the dashboard body.