Filtering a DataTable by button / one click (R Flexdashboard)

Question

I am using DT::datatable in a Flexdashboard to provide some monthly KPIs for about 100 different countries. Five of them are of special interest to some of the dashboard’s users, so I am searching for a solution to easily filter on those countries.

My idea was to generate a button next to the Export Buttons that will filter the data on only those five rows. Clicking it again would most perfectly show the original table again. I found that there is a possibility to specify custom buttons but still I have no clue how to tackle my problem with this.

Here is a tiny example of the table I get so far:

# Random Data Frame
df <- data.frame(Country = paste("Country", 1:100, sep = "_"), 
                 Revenue = rnorm(n = 100, mean = 5000, sd = 2000))

# Data Table used in Dashboard
datatable(df, class = "hover", rownames = FALSE , extensions = 'Buttons', options = list(
  pageLength = 5,
  responsive = TRUE,
  dom = 'Bftip',
  buttons = c('copy', 'csv'),
  columnDefs = list(list(className = 'dt-center', targets = "_all"))
)) %>% formatCurrency(columns = "Revenue")

Thanks for any help!

Answer 1

Below is a reproducible example in Shiny as I do not think what you are trying to do is feasible in a static document. I assume you have set runtime: shiny.

library(DT)
library(shiny)

countries <- data.frame(
  cns = LETTERS,
  value = runif(26, 1, 4)
)

TOP5 <- c("A", "B", "X", "Y", "Z")

ui <- fluidPage(
  actionButton("filter", "Filter countries of interest"),
  DTOutput("table")
)

server <- function(input, output, session) {

  output$table <- renderDT({

    sel <- if(input$filter %% 2 == 0) countries$cns else TOP5

    countries %>% 
      filter(cns %in% sel) %>% 
      datatable()
  })

}

shinyApp(ui, server)