observeEvent with showModal

[tanthiamhuat]

I wish to display a dialog saying "No Barcode Scanned" when user clicks Save Data button when its textbox of Barcode is empty (i.e input$Barcode). But below does not display that dialog. Can anyone help? Thanks.

observeEvent(input$save_data,{
  req(input$Barcode)
  if (is.null(input$Barcode)) {   
    showModal(modalDialog(
      title = "No Barcode Scanned",
      "Please scan a barcode in the textbox.",
      easyClose = TRUE
    ))
    jqui_draggable(selector = '.modal-content')
  } else {
   ###  blah blah  do something

 }    

[nirgrahamuk]

@tanthiamhuat

req(input$Barcode)

This would stop evaluating before you check if it's empty (if it's empty)

[tanthiamhuat]

@nirgrahamuk

ld stop evaluating before you check if it'

hmm.. remove that above link will crash the application when its textbox is empty, and when Save data button is pressed.

[nirgrahamuk]

Then if req guarantees your barcode is populated, remove the null check after it and the message to user about it not being populated ?

[tanthiamhuat]

but what I need is to show that dialog box of empty barcode when it is empty and user presses the button.

[tanthiamhuat]

or alternativesly, if that text box is empty, I want to disable that button. I try that, but it does not work too.

#ui.R
shinyjs::useShinyjs()
uiOutput("SaveData")
textInput("Barcode", h4("Scan and press Save Data button"))

# server.R
output$SaveData <- renderUI({
  tagList(
    bsModal("modalSaveData", "Save Data", "save_tmp_data", size = "small",wellPanel(
      h3('Are you sure you want to save the data?'),
      actionButton("save_data", "Save"),
      actionButton("cancel_data", "Cancel")
    )),
    actionButton('save_tmp_data','Save Data')
  )
})

observe({
  input$Barcode
  if (input$Barcode == '') {
    shinyjs::disable("save_tmp_data")
  }
})

[nirgrahamuk]

A proper reprex would reduce the upfront costs on any would be helper (like myself) to run your code