title: Shiny dashboardSidebar change when different tabItem selected
body: <p>I am having a following problem:</p>
  
  <p>I want a sidebar change when I switch between tabItem(s).</p>
  
  <pre><code>dashboardPage(
  dasboardHeader(title = ""),
  dashboardSidebar(
    sidebarMenu(
      menuItem("1", tabName = "1"),
      menuItem("2", tabName = "2")     
               ),
  #I want this to be displayed when menuItem "1" is clicked
        tabsetPanel(
              tabPanel("t1", val="t1",
                      .... some inputs),
              tabPanel("t2", val="t2",
                      .... some inputs)
                   ),
   # This to be displayed when menuItem "2" is clicked    
        selectInput("s1", label="Select"....),
        selectInput("s2", label="Select2"...)
    )
  dashboardBody(
   tabItem(tabName="1", 
        .......
     ),
   tabItem(tabName="2",
        ........
     )
   )
  )
  </code></pre>
  
  <p>I have the dashboardBody changing when switching between the tabs but don't know how to change the dashboardSidebar values. Tried this inside the dashboardSidebar:</p>
  
  <pre><code> conditionalPanel(
               condition="tabName='1'",
            #displaying first version of DashboardSidebar
               ),
   conditionalPanel(
               condition="tabName='2'",
            #displaying second version of DashboardSidebar
               )
  </code></pre>
  
  <p>But it didn't work for me.</p>
  
  <p>Any ideas? </p>
  
  <p>Thank you for your help.</p>