title: How to create variable inside Taglist environment Shiny
body: <p>I am building a shiny dashboard with different input widgets. I want the options given in one widget to be dependent on the input in previous widget. For example, I have a <code>pickerInput</code> item where one can specify a variable from my dataset (<code>df</code>). Next, I want to display <code>checkboxGroupInput</code> where you can select the unique values of the earlier chosen variable. Therefore, the <code>choices</code> variable in <code>checkboxGroupInput</code> should be a list containing all unique values from the earlier chosen variable. My code now looks like this: </p>
  
  <pre><code> tagList(
       pickerInput(inputId = "select_add",
                   label = "Select variable:",
                   choices = list(grouplist_1),
                   selected = NULL
                  ),
  
                  list_members = c(unique(as.data.frame(df)[input$select_add])),
  
                  conditionalPanel(condition = "input.Name_add_member1.length &gt; 0",
                                   checkboxGroupInput(inputId = "def_members", label = "Define",
                                   choices = list_members)
  
   )
  </code></pre>
  
  <p>In the code, the <code>list members</code> generates a list with the unique values in the chosen variable. However, it looks like this line is not executed here. Does anyone know how to solve this?</p>