Suggestion: Add a working example of 'Select All' and 'Select None' buttons to the documentation

[warnes]

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I needed to add 'Select All' and 'Select None' buttons that work with the select functionality. After quite a bit of searching and experimenting, I found this post on stack overflow showed the necessary approach to creating a button that will trigger a Shiny event: https://stackoverflow.com/a/69351894/21282358.

This is a simple demonstration of the approach for 'Select All' and 'Select None':

library(shiny)
library(DT)

shinyApp(
  ui = fluidPage(
    DTOutput('tbl')
    ),
  
  server = function(input, output) {
    output$tbl = 
      renderDT(
        datatable(
          iris,
          select = 'multiple',
          extensions=c(
            "Buttons"
          ),
          options = list(
            dom = 'Blfrtip',
            buttons = list(
              list(
                extend = 'collection',
                text = 'Select All',
                action = DT::JS(
                  r"(
                  function() {
                      var node = this[0].node;
                      var value = $(node).attr('data-value') || 0;
                      value ++;
                      $(node).attr('data-value', value);
                      Shiny.setInputValue('select_all_btn', value, {priority: 'event'});
                  }
                  )"
                )
              ),
              list(
                extend = 'collection',
                text = 'Select None',
                action = DT::JS(
                  r"(
                function() {
                    var node = this[0].node;
                    var value = $(node).attr('data-value') || 0;
                    value ++;
                    $(node).attr('data-value', value);
                    Shiny.setInputValue('select_none_btn', value, {priority: 'event'});
                }
                )"
                )
              ),
              'copy',
              'csv',
              'excel',
              'print'
            )
          )
        )
      )
    
    
    observeEvent(
      input$select_all_btn,
      {
        DT::dataTableProxy('tbl') |>
          selectRows(selected=1:nrow(iris))
      }
    )
    
    
    observeEvent(
      input$select_none_btn,
      {
        DT::dataTableProxy('tbl') |>
          selectRows(selected=NULL)
      }
    )
  }
)

Perhaps an example like this could be added to the documentation to make if easier for folks to find, at least until integration of the new datatable 'Select' extension is complete.