SelectInput loading slow 60000 items

[Jemkon]

Hi,
I am using development version of shiny 1.0.5.9000. I have 60000 items in my selectInput and its extremely slow.

Here is the code:
sever.R

    output$choose_Genes <- reactiveUI(function() {

    #selectInput(inputId = "Genes", label = "Genes of interest", multiple = TRUE, choices = c("Select Gene", as.list(GeneNames))
    selectizeInput(inputId = "Genes", label = "Genes of interest", multiple = TRUE, choices = c("Select Gene", as.list(GeneNames)),
      options = list(maxOptions = 100))                          
    })

ui.R

    uiOutput("choose_Genes")

The GeneNames is the list of 60000 genes. I have also used selectizeInput but still very slow.

Any idea How I can improve the loading time.

Many thanks.

[jcheng5]

See the section on server-side selectize here: https://shiny.rstudio.com/articles/selectize.html

[Jemkon]

Thanks jcheng5. I have changed the code according to the server-side selectize. But i got following error.

Error in .getReactiveEnvironment()$currentContext() :
Operation not allowed without an active reactive context. (You tried to do something that can only be done from inside a reactive expression or observer.)

Do I need to put updateSelectizeInput(session, 'Genes', choices = c('Select Gene', as.list(GeneNames)), server=TRUE) into observe function?

I have placed it in server function.

Thanks.

[wch]

Yes, you need to put updateSelectizeInput() in an observe().

EDIT: sorry, I was wrong -- it doesn't need to go in an observe function. Here's a minimal example:

shinyApp(
  fluidPage(
    selectizeInput("foo", "Foo", choices = NULL)
  ),
  function(input, output, session) {
    updateSelectizeInput(session, 'foo', choices = c("a", "b"), server = TRUE)
  }
)

[Jemkon]

Hi wch,
Not working. still got the same error. If I put it in observe function then I dont get error but the selectizeInput is empty.

ui.R

    uiOutput("selectGenes")

server.R

    server <- function(input, output, session) {
            updateSelectizeInput(session, 'Genes', choices = c('Select Gene', as.list(GeneNames)), server=TRUE)

           output[["selectGenes"]] <- renderUI({
                     selectizeInput(inputId = "Genes", label = "Genes of interest", choices = NULL)
               })
        }

Anything wrong with the code?

Many thanks.

[wch]

The problem is that the updateSelectizeInput runs as soon as the app starts, before the selectizeInput is rendered on the page (because it is rendered with renderUI). If selectizeInput were directly in the UI (that is, not with renderUI), then it would work without putting updateSelectizeInput in observe()