Counting button clicks

[Dennis Andersen]

I am new to Shiny and playing around with the interface. I thought I would try and make a simple click counter app, where a textOutput displays the number of clicks on an actionButton.

I have the following in the ui.R file

textOutput("clickCount")
actionButton("clickBtn", "Click")

In the server.R file I have

library(shiny)
clickCounter <- 0
shinyServer(function(input, output) {
 
  output$clickCount <- renderText({
    input$clickBtn
    clickCounter <- isolate(clickCounter + 1)
    clickCounter
    })
 
})

First of all, when the app loads the textOutput displays 1 and not 0. Secondly, nothing happens to the clickCounter when I click the button. I wanted to increase the number in textOutput("clickCount") by 1 every time the button is clicked.. is it possible or am I chasing windmills? :)

Thanks,
Dennis

[Oliver Gjoneski]

Hi Denis!

Not chasing windmills at all!  You just need to use the fact that the actionButton variable is already a counter that's initialized at zero.   The following should do what you want:

shinyApp(

  ui = fluidPage(responsive = FALSE

    ,fluidRow(style = "padding-bottom: 20px;"

      ,column(width=6,

        textOutput("clickCount")

      )

      ,column(width=6,

        actionButton("clickBtn", "Click")

      )

    )

  )

  ,server = function(input, output, session) {

    output$clickCount <- renderText({

        input$clickBtn

    })

  }

  ,options = list(height = 500)

)