Trying to dynamically create a list of questions in Shiny


I am trying to create a list of questions that are displayed based on the category and the number of questions.

I have found a way to create the question list using lapply and modules, but it does not behave as expected.

I cannot select a radio button. When I do, it resets all the buttons and does not record an answer. I cannot figure out what the issue is.

Please help with either a diagnosis or an alternative means of doing this.

The necessary files are located on GitHub.


So my question has changed. After much trial and mostly error, I can now generate the list of radio buttons correctly, and they do not reset when one is selected.

Now how do I access the selections made? The module based name space is not accessible outside the module so the dynamically generated namespace ID’s for each radioButton cannot be accessed usng input$ID. This appears to work differently because of the use of modules.

The code in my example on Github has been updated to my latest. (See the Github link above)


Modules can return reactive objects which are then accessible in the "master". As a minimal example:

mod_server = function(input,output,session){
  autoInvalidate = reactiveTimer(1000)
  rv = reactiveValues(x = NULL)
    # update the reactive value x every second with random value
      rv$x = runif(1)

ui = fluidPage(textOutput("out"))
server = function(input,output,session){
  # binding for returned reactivevalues from module
  modulevalue = callModule(mod_server,"id")
  # x is the object in the reactivevalues that contains the random number
  output$out = renderText(modulevalue$x)