How to call choice name instead of value in Shiny? - r

Question

I'm working on a dashboard where sometimes I need to call the input's choice name and other times it's value, but I only know how to get the latter. Is there a way to call the first one?
Here is a minimum reproducible example:
library(shiny)
library(shinydashboard)
ui <- dashboardPage(
header = dashboardHeader(),
sidebar = dashboardSidebar(),
body = dashboardBody(
selectInput(
"input",
h5("The output should give the choice name instead of it's value"),
choices=c(
"Name 1" = 1,
"Name 2" = 2,
"Name 3" = 3
)
),
textOutput("output")
)
)
server <- function(input, output, session) {
output$output <- renderPrint({paste(input$input)})
}
shinyApp(ui = ui, server = server)

Answer 1

I think it is easiest to create a data.frame with the choices and the corresponding names in advance, and use that to look up the name of the selected input. A working example is given below, hope this helps!
library(shiny)
library(shinydashboard)
choices_df = data.frame(
names = c('Name 1', 'Name 2', 'Name 3'),
id = seq(3)
)
ui <- dashboardPage(
header = dashboardHeader(),
sidebar = dashboardSidebar(),
body = dashboardBody(
selectInput(
"input",
h5("The output should give the choice name instead of it's value"),
choices= setNames(choices_df$id,choices_df$names)
),
textOutput("output")
)
)
server <- function(input, output, session) {
output$output <- renderPrint({paste(choices_df$names[choices_df$id==input$input])})
}
shinyApp(ui = ui, server = server)