title: Shiny Image output not found
body: <p>i am running this shiny app below and i keep getting the following error</p>
  <pre><code>Warning: Error in &lt;-: object 'output' not found
    [No stack trace available]
  Error in output$x &lt;- renderImage({ : object 'output' not found
  </code></pre>
  <p>The app is displayed in google chrome but the pages are greyed out with features from previous code running, i assume this is because i havent fixed the error however i have tried to make the following code identical to what i did before and still get the error.</p>
  <p>this is my ui.r code</p>
  <pre><code>library(shiny)
  library(leaflet)
  library(shinythemes)
  library(shinyjs)
  library(bootstrap)
  
  ui &lt;- fluidPage(theme = shinytheme(&quot;cerulean&quot;),
  
                  navbarPage(
                    title = (&quot;Printacles&quot;),
                    tabPanel(&quot;Home&quot;, &quot;This panel is intentionally left blank&quot;),
                    tabPanel(&quot;Get Started&quot;,
                               sidebarPanel(
                               tags$h3(&quot;Input prescription:&quot;),
                               numericInput(&quot;num1&quot;, &quot;SPH:&quot;, &quot;&quot;),
                               numericInput(&quot;num2&quot;, &quot;AXIS:&quot;, &quot;&quot;),
                               numericInput(&quot;num3&quot;, &quot;CYL:&quot;, &quot;&quot;),
                               selectInput(&quot;picture&quot;, &quot;Choose Your Frame:&quot;,
                                            c(&quot;Round Eye&quot;, &quot;Wayfarer&quot;, &quot;Square&quot;)),
                               br(),
                               submitButton(&quot;Submit&quot;)
                             ),
                             column(4,
                             imageOutput(&quot;x&quot;, height = 100)
                                  
         
                    ),
                    ),
          
  
                    tabPanel(&quot;Pricing&quot;, &quot;This panel is intentionally left blank&quot;),
                    tabPanel(&quot;Models&quot;, &quot;This panel is intentionally left blank&quot;),
                    tabPanel(&quot;FAQ&quot;, &quot;This panel is intentionally left blank&quot;)
                    
                  ) # navbarPage
  ) # fluidPage
  
  </code></pre>
  <p>and my server.r is</p>
  <pre><code>output$x &lt;- renderImage({
    if (is.null(input$picture))
      return(NULL)
    
    if (input$picture == &quot;Round Eye&quot;) {
      return(list(
        src = &quot;pics/Round Eye.jpg&quot;,
        filetype = &quot;image/jpeg&quot;,
        alt = &quot;Round eye&quot;
      ))
    } else if (input$picture == &quot;Wayfarer&quot;) {
      return(list(
        src = &quot;pics/Wayfarer.jpg&quot;,
        filetype = &quot;image/jpeg&quot;,
        alt = &quot;Wayfarer&quot;
      ))
    }
    
  }, deleteFile = FALSE)
  </code></pre>
  <p>I have looked for answers but found no fix. If anyone can help me out it would be greatly appreciated.</p>