CODEWITHSUNDEEP
shiny
Geovany
Geovany

Reputation: 5677

Shiny "updateCheckboxGroupInput" inconsistency

I don't know if this is a bug of just a feature, but the updateCheckboxGroupInput function in Shiny is not working consistently. When I update the group with selected=FALSE to deselect all the choices, the related reactive components (observer, UI elements) doesn't change anything. I know that there are many ways to do this task, my point here is to show the lack of consistency of the updateCheckboxGroupInput with the selected parameter.

Here is simplified example that represents the problem using a couple of action buttons to select/deselect all the choices on the group. After updating with selected=FALSE, all the choices are deselected but the change does not affect the reactive components associated (in this case verbatimTextOutput) as is the case of selecting all.

Can someone explain me why the updateCheckboxGroupInput is not working as expected?

  choices <- letters[1:5]
  runApp(list(
    ui = basicPage(
      checkboxGroupInput('chkGrp', 'Options', choices),
      actionButton("all","All"),
      actionButton("none","None"),
      verbatimTextOutput("value")
    ),
    server = function(input, output, session) {
       output$value <- renderPrint({ input$chkGrp })
       observe({
          if ( is.null(input$all) || input$all == 0)
               return()
          updateCheckboxGroupInput(session,"chkGrp",selected=choices )
       })
       observe({
          if ( is.null(input$none) || input$none == 0)
               return()
          updateCheckboxGroupInput(session,"chkGrp",selected=FALSE)
       })
    }
  ))

Upvotes: 2

Views: 1594

Answers (1)

Pork Chop
Pork Chop

Reputation: 29387

When you use the updateCheckboxGroupInput you still have to provide what goes in there.

#rm(list = ls())
library(shiny)
choices <- letters[1:5]
runApp(list(
  ui = basicPage(
    checkboxGroupInput('chkGrp', 'Options', choices),
    actionButton("all","All"),
    actionButton("none","None"),
    verbatimTextOutput("value")
  ),
  server = function(input, output, session) {
    output$value <- renderPrint({ input$chkGrp })
    observe({
      if ( is.null(input$all) || input$all == 0)
        return()
      updateCheckboxGroupInput(session,"chkGrp",selected=choices )
    })
    observe({
      if ( is.null(input$none) || input$none == 0)
        return()
      updateCheckboxGroupInput(session,"chkGrp",choices = choices,selected=NULL)
    })
  }
))

Upvotes: 2

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