R shiny arrangment of horizontal checkboxes

December 21, 2022

I am new to shiny applications and I cannot figure out how to arrange some of the aspects of it. I currently have the following shiny code (along with the image of the output)

library(shiny)
channels <- c("social","digital","twitter")

ui <- shinyUI(fluidPage(
  titlePanel("List Elements"),
  sidebarLayout(
    sidebarPanel(
      width = 2,
      tableOutput("listTable")
    ),
    mainPanel(
      checkboxGroupInput(inputId="test", label="Test", choices=1:4, inline = TRUE)
    )
  )
))

# server.R

server <- shinyServer(function(input, output){
  output$listTable <- renderTable({
    channels  })

})


shinyApp(ui = ui, server = server)

I would like to have multiple lines of check boxes for each word that appears on the left hand side which can vary in number. However I cannot figure out how to do so, I only know how to hard code in a certain number of lines.

Eg For the example above I would like the output to be:

>Solution :

this could be achieved using lapply in combination with renderUI in ther server function and calling UIOutput in the Ui function. See example below:



library(shiny)
channels <- c("social","digital","twitter")

ui <- shinyUI(fluidPage(
  titlePanel("List Elements"),
  sidebarLayout(
    sidebarPanel(
      width = 2,
      tableOutput("listTable")
    ),
    mainPanel(
      uiOutput("CheckBox")
     
    )
  )
))

# server.R

server <- shinyServer(function(input, output){
  output$listTable <- renderTable({
    channels  })

  output$CheckBox <- renderUI({
    lapply(seq_along(channels), function(i) {
        checkboxGroupInput(inputId=paste0("test",i), label=channels[i],choices=1:4, inline = TRUE)
    })
  })
})


shinyApp(ui = ui, server = server)