Shiny renderUI SelectInput won't update

Question

I'm trying to update the value shown in textInput based on selectInput. I originally didn't have the if-else statement in output$text, but based on suggestions from other questions, added it, but it still didn't work. I then tried the solution from "Shiny renderUI selectInput NULL", but that didn't work either.

Portion from server.r:

  names <- list("A"=1, "B"=2, "C"=3, "D"=4, "E"=5, "F"=6, "G"=7, "H"=8, "I"=9)
  
  # UI
  output$view <- renderUI({
    selectInput("viewTopic", "View Topic:", choices = names, selected = 1)
  })
  
  output$text <- renderUI({
    if(is.null(input$viewTopic)){
      return()
    }else{
      textInput("docTitle", label = "Topic Name:", value = names[input$viewTopic])
    }
  })

Currently, "value" in textInput is just NULL. How can I make the value for textInput update based on the selectInput?

Sorry, confusing comment. This is my server file. That comment is to denote the part of it that directly interacts with the UI. — Andrew, Aug 05 '15 at 16:23

score 1 · Accepted Answer · answered Aug 05 '15 at 07:18

Is this what you want?

rm(list = ls())
library(shiny)
names <- list("A"=1, "B"=2, "C"=3, "D"=4, "E"=5, "F"=6, "G"=7, "H"=8, "I"=9)

ui =(pageWithSidebar(
  headerPanel("Test Shiny App"),
  sidebarPanel(
    selectInput("viewTopic", "View Topic:", choices = names, selected = 1),
    #display dynamic UI
    uiOutput("text")),
  mainPanel()
))

server = function(input, output, session){

  output$text <- renderUI({
      textInput("docTitle", label = "Topic Name:", value = as.character(input$viewTopic))
  })  
}
runApp(list(ui = ui, server = server))

Bah. Thank you! My issue was converting input$viewTopic into a character. — Andrew, Aug 05 '15 at 16:27

Shiny renderUI SelectInput won't update

1 Answers1