Q:

Keyboard shortcuts to trigger reactive flows in R Shiny?

Is it possible to have, say, F7 or Q trigger a reactive flow in a Shiny app (in Windows)? This question provides code for alternating tabs with keyboard input, but I am interested in starting reactive flows. For example, a button is 'triggered' every time the user presses Q in the keyboard.

A:

Here's an example based on this answer:
library(shiny)

runApp(shinyApp(
  ui = fluidPage(
    tags$script(HTML("$(function(){ 
      $(document).keyup(function(e) {
      if (e.which == 81) {
        $('#button').click()
      }
      });
      })")),
    actionButton("button", "An action button"),
    textOutput("text")),
  server=function(input, output, session) {
    output$text <- renderText({input$button})
  }
))

You can use this page to find the keycode you want to use in the javascript code. 
In this example, if q is pressed, the element with the id button is clicked.

