Update of the variable by constant in shiny - r

Question

The community helped me in developing this code
library(shiny)
server <- shinyServer(function(input, output, session) {
values <- reactiveValues()
values$df <- data.frame(N = numeric(0), A = numeric(0), C = numeric(0))
newEntry <- observeEvent(input$update,{
gr <- 10 + input$n
newLine <- isolate(c(input$n, input$nr1, gr))
values$df[nrow(values$df) + 1,] <- c(input$n, input$nr1, gr)
})
output$table1 <- renderTable({values$df})
})
ui <- shinyUI(fluidPage(
titlePanel("submitButton example"),
fluidRow(
column(3, wellPanel(
sliderInput("nr1", "Give a number: ", min = 0, max = 100, value = 0, step = 2),
sliderInput("n", "N:", min = 10, max = 1000, value = 200, step = 10),
actionButton("update", "Update Table"))),
column(6, tableOutput("table1"))
)
))
shinyApp(ui, server)
And I come to a new problem with that.
Now, I'd like that the app do like this: on click on the update, the variable A should always add a 5 i.e. if I have starting value of 5 than on the next click it should be 10 than 15, 20 etc?
Now when I click update the same number appears continously

Answer 1

Is this what you want? Also you dont need the isolate in there.
rm(list = ls())
library(shiny)
ui <- shinyUI(fluidPage(
titlePanel("submitButton example"),
fluidRow(
column(3, wellPanel(
sliderInput("nr1", "Give a number:", min = 1, max = 100, value = 1, step = 1),
sliderInput("n", "N:", min = 10, max = 1000, value = 200, step = 10),
actionButton("update", "Update Table"))),
column(6, tableOutput("table1"))
)
))
server <- shinyServer(function(input, output, session) {
values <- reactiveValues()
values$df <- data.frame(N = numeric(0), A = numeric(0), C = numeric(0))
newEntry <- observeEvent(input$update,{
if(!is.null(input$nr1) & is.null(values$A)){
values$A <- input$nr1
}
if(nrow(values$df) > 0){
values$A <- values$A + 5
}
gr <- 10 + input$n
values$df[nrow(values$df) + 1,] <- c(input$n, values$A, gr)
})
output$table1 <- renderTable({values$df})
})
shinyApp(ui, server)