change label of shiny button and counting clicks - r

Question

I was trying to switch the label of a show/hide columns button, and also keep the track of the number of times it is clicked in order to alter the number of columns showed of a table. I made it, but I couldn't use a direct even/odd differentiation of the value of the counter. Instead I had to use this: (vars$counter+1)/2) %% 2 == 0) to make it work, because each click changes the counter 2 times. I would like to request an easier procedure, maybe there is a shinyBS for that?
## app.R ##
library(shiny)
library(shinydashboard)
library(DT)
body<-dashboardBody(
textOutput("count"),
uiOutput('showallcolumnsbutton'),
DT::dataTableOutput('table2')
)
ui <- dashboardPage(
dashboardHeader(),
dashboardSidebar(),
body
)
server <- function(input, output) {
table<-data.frame(replicate(10,sample(0:1,1000,rep=TRUE)))
vars<-reactiveValues()
vars = reactiveValues(counter = 0)
observe({
if(!is.null(input$showallcolumns)){
input$showallcolumns
isolate({
vars$counter <- vars$counter + 1
})
}
})
label <- reactive({
if(!is.null(input$showallcolumns)){
if( ( (vars$counter+1)/2) %% 2 == 0) label <- "Hide"
else label <- "Show"
}
})
output$showallcolumnsbutton <- renderUI({
actionButton("showallcolumns", label = label(),
icon("hand-pointer-o"),
style="color: #000; background-color: #0099ff; border-color: #2e6da4"
)
})
output$count<-renderText({paste("counter value:",vars$counter)})
columnstoshow = reactive ({
x= ((vars$counter+1)/2) # %% 2 == 0)
if (!is.null (x))
{
if (x %% 2 == 0) {
c=c(1:10)
}
else {
c=c(1:5)
}
} #end 1st if
else {
c=c(1:10)
}
})
output$table2 = DT::renderDataTable({
DT::datatable(table[, columnstoshow()])
})
} # end server
shinyApp(ui, server)

Answer 1

Since Im not 100% what you want, is this it? Note that I used other library such as shinyBS
rm(list = ls())
library(shiny)
library(shinydashboard)
library(DT)
library(shinyBS)
body <- dashboardBody(bsButton("showallcolumns", label = "Hide", block = F, style="danger",icon=icon("hand-pointer-o")),br(),DT::dataTableOutput('table2'))
ui <- dashboardPage(dashboardHeader(),dashboardSidebar(),body)
server <- function(input, output,session) {
table <- data.frame(replicate(10,sample(0:1,1000,rep=TRUE)))
vars <- reactiveValues(counter = 1:10)
observeEvent(input$showallcolumns,{
if(input$showallcolumns %% 2){
updateButton(session, "showallcolumns",label = "Show", block = F, style = "success",icon=icon("hand-pointer-o"))
vars$counter <- 1:5
}
else{
updateButton(session, "showallcolumns",label = "Hide", block = F, style = "danger",icon=icon("hand-pointer-o"))
vars$counter <- 1:10
}
})
output$table2 = DT::renderDataTable({
DT::datatable(table[, vars$counter])
})
} # end server
shinyApp(ui, server)