title: shinyBS Modal within checkbox group
body: <p>I use <code>shinyBS::bsModal()</code> to place explanations of the UI elements there. It works great when I place a <code>bsButton()</code> behind the title of the checkbox.</p>
  
  <p>Now I want to place it behind the checkbox options.
  A first hint could be <a href="https://stackoverflow.com/questions/36670065/tooltip-in-shiny-ui-for-help-text/36696224#36696224">this answer</a> where the same for a tooltip is done (but my modification do not work).</p>
  
  <p>Minimal Example:</p>
  
  <pre><code>library(shiny)
  library(shinyBS)
  
  ui &lt;- fluidPage(
    sidebarLayout(
      sidebarPanel(
        checkboxGroupInput("qualdim",  
                           tags$span("Chekboxoptions",   
                               bsButton("modalbt", "?", style = "inverse", size = "extra-small")),
  
                           c("Option_1" = "Option_1", 
                             "Option_2" = "Option_2"))
      ),
  
      mainPanel(
        bsModal("modalExample", "Modal", "modalbt", size = "large",
             verbatimTextOutput("helptext")))
    )
  )
  
  server &lt;- function(input, output) {
    output$helptext &lt;- renderText({"I can trigger a shinyBS::bsModal() from here, but I want to place two buttons behind `Option_1` and     `Option_2`" })
  }
  
  shinyApp(ui = ui, server = server)
  </code></pre>