R shiny conditionalPanel displaying both conditions - r

Question

I am trying to a multi tab app, I want the the second tab's page layout to be conditional on an input from the first panel. Basically if the value in the first panel is 1 I want the second panel to display 1 set of file inputs if the user puts in the value 2 in the first panel then I want the second panel to display 2 file inputs. Currently my code displays both conditions, and I am unsure why. See the reproducible code below.
ui =
navbarPage("Page Title",
tabPanel("Panel 1",
sidebarPanel(
## Add Name,
## Number of surveys analysising
numericInput("n_values", "Number of columns in next panel:", 1, min = 1, max = 2)
),
mainPanel(
tags$div(
h2("Home Page")
)
)
),
tabPanel("Panel 2",
conditionalPanel(condition = "input.n_values == 1",
fixedPage(theme = "flatly",
fixedRow(
column(2,"First Column",
fileInput("File1", "Choose a CSV files",accept = c("text/csv","text/comma-separated-values",".csv"), multiple = F),
p("Click the button to check the data was read in correctly")
),
fixedRow(
column(12,
verbatimTextOutput("errorText")
)
)
)
)
),
conditionalPanel(condition = "input.n_values == 2",
fixedPage(theme = "flatly",
fixedRow(
column(2,"First Column",
fileInput("File1", "Choose a CSV files",accept = c("text/csv","text/comma-separated-values",".csv"), multiple = F),
p("Click the button to check the data was read in correctly")
),
column(2,"Second Column",
fileInput("File2", "Choose a CSV files",accept = c("text/csv","text/comma-separated-values",".csv"), multiple = F),
p("Click the button to check the data was read in correctly")
),
fixedRow(
column(12,
verbatimTextOutput("errorText")
)
)
)
)
)
)
)
server = function(input, output,session) {
## Call the error message function and print
output$errorText <- renderText({
validate(
need(!is.null(input$File1)
, 'You need to input the files before we can validate the data. Please select all the necessary files.')
)
})
}
shinyApp(ui, server)

Answer 1

That's because you have verbatimTextOutput("errorText") twice in your UI. You can't do that in Shiny. An output must be included at one place only.