make conditionalPanel appears when RData file is loaded in shinydashboard - r

Question

I am making a shiny app that interacts with a big data.frame that I have stored as an RData file. I want the user to select the file, and once the RData is completely loaded (takes ~15 seconds) a second panel should show up allowing the user to input some sample name and do some operations.
Here is how my app looks now
header <- dashboardHeader(title="Analysis and database")
sidebar <- dashboardSidebar(
useShinyjs(),
sidebarUserPanel(),
hr(),
sidebarMenu(
# Setting id makes input$tabs give the tabName of currently-selected tab
id = "sidebarmenu",
menuItem("Analyse old data by Sample", tabName="oldfile", icon = icon("table"), startExpanded = FALSE),
fileInput(inputId = "file1", "Choose database file"),
conditionalPanel(
#condition = "input.sidebarmenu === 'oldfile'",
condition = "output.fileUploaded == 'true' ",
textInput(inputId = "sample", label ="Type a sample ID"),
actionButton("go2", "Filter")
)
)
)
body <- dashboardBody(
tags$style(type="text/css",
".shiny-output-error { visibility: hidden; }",
".shiny-output-error:before { visibility: hidden; }"),
tabItems(
tabItem("oldfile", "Sample name data.table",
fluidRow(DT::dataTableOutput('tabla_oldfile') %>% withSpinner(color="#0dc5c1")))
)
)
ui <- dashboardPage(header, sidebar, body)
### SERVER SIDE
server = function(input, output, session) {
options(shiny.maxRequestSize=100000*1024^2)
prop <- reactive({
if (input$go2 <= 0){
return(NULL)
}
result <- isolate({
if (is.null(input$file1))
return(NULL)
if (is.null(input$sample))
return(NULL)
inFile <- input$file1
print(inFile$datapath)
#big_df <- load(inFile$datapath)
print (big_df)
print(input$sample)
oldtable <- big_df1 %>% filter_at(vars(GATK_Illumina.samples:TVC_Ion.samples),
any_vars(stringi::stri_detect_fixed(., as.character(input$sample))))
oldtable
})
result
})
output$fileUploaded <- reactive({
return(!is.null(prop()))
})
outputOptions(output, 'fileUploaded', suspendWhenHidden=FALSE)
output$tabla_oldfile <- DT::renderDataTable({
DT::datatable(prop(),
filter = 'top',
extensions = 'Buttons',
options = list(
dom = 'Blftip',
buttons =
list('colvis', list(
extend = 'collection',
buttons = list(list(extend='csv',
filename = 'results'),
list(extend='excel',
filename = 'results'),
list(extend='pdf',
filename= 'results')),
text = 'Download'
)),
scrollX = TRUE,
pageLength = 5,
lengthMenu = list(c(5, 15, -1), list('5', '15', 'All'))
), rownames = FALSE
)
})
}
shinyApp(ui, server)
I have used the solution provide in Make conditionalPanel depend on files uploaded with fileInput but I can't make it work, there is another implementation using shinyjs package but don't know how to use it on my example