title: can I use updateTextInput() within shiny modules?
body: <p>I have written a fairly straight forward module, consisting of a textInput on the client and a server function that updates the value of that textInput. To accomplish this, I call updateTextInput() in the server function. However, the textInput on the client is NOT updated.</p>
  
  <p>What should I do to have my module server function update the textInput on the client?</p>
  
  <p>Here is a simplified version of my code:</p>
  
  <p>global.R with module definition</p>
  
  <pre><code># Client side. 
  specifyInput &lt;- function(id, points){  
      ns &lt;- NS(id)
      tagList(textInput(ns('points'), label='Total', value=points))
  }
  
  # Server side. 
  specify &lt;- function(input, output, session){
      ns &lt;- session$ns
  
      observe({
          new.value = 2 * as.numeric(input$points)
          #this line does not seem to work
          updateTextInput(session, ns('points'), value = new.value)
      })
  
      # create dataframe with entered value
      df &lt;- reactive(data.frame(points = as.numeric(input$points)))
  
      # return the dataframe
      return(df())
  }
  </code></pre>
  
  <p>ui.R </p>
  
  <pre><code>    specifyInput("ttlEntry", 10)
  </code></pre>
  
  <p>server.R </p>
  
  <pre><code>        function(input, output, session){
            test &lt;- reactive(callModule(specify, "ttlEntry"))
  
            #somewhere in the code, call test()
          }
  </code></pre>
  
  <p>In reality, I want to attach a .5 behind the entered value when the user enters a period, for example if user enters "10." then the textInput is updated to display "10.5" 
  However for testing purposes, I have changed that code to new.value = 2 * ...  </p>
  
  <p>Any help is greatly appreciated.</p>