R Shiny Key Input Binding

R Shiny key input binding

You can add a listener for keypresses. The Shiny.onInputChange can be used to bind the key pressed to a shiny variable:

library(shiny)
runApp( list(ui = bootstrapPage(
  verbatimTextOutput("results"),
  tags$script('
    $(document).on("keypress", function (e) {
       Shiny.onInputChange("mydata", e.which);
    });
  ') 
)
, server = function(input, output, session) {

  output$results = renderPrint({
    input$mydata
  })
}
))

for keydown events you can substitute:

  tags$script('
    $(document).on("keydown", function (e) {
       Shiny.onInputChange("mydata", e.which);
    });
  ') 

R Shiny key and actionButton binding to reactive values

The problem is that the input event only captures the keycode of the pressed key, which stays the same once the key is pressed. Shiny however only reacts if the event data changes. You need to set the event data to something new every time; e.g. the current time stamp. Look at this working example:

library(shiny)
shinyApp(ui <- pageWithSidebar(
  headerPanel("Test keyboard control"),
  sidebarPanel(
    tags$script('$(document).on("keydown",
                 function (e) {
                 if(e.which == 68) {
                   Shiny.onInputChange("downButton", new Date());
                 } else if (e.which == 85) {
                   Shiny.onInputChange("upButton", new Date());
                 }
                 });
                '),
    actionButton("downButton", "Down"),
    actionButton("upButton", "Up")
  ),
  mainPanel(htmlOutput("text"))
),

server <- function(session, input, output) {
  vals <- reactiveValues(count = 0)

  observeEvent(input$downButton, {vals$count <- vals$count - 1})
  observeEvent(input$upButton, {vals$count <- vals$count + 1})

  output$text <- renderText(paste("Counter is:", vals$count))
}
)

Shiny: How to hide and show elements based on keypress / key. input

Try this, I added the keys (e,i, SHIFT+e, SHIFT+i)

library(shiny)
library(ggplot2)

ui <- fluidPage(
    useShinyjs(),
    div(
        id = "welcome",
        mainPanel(
            fluidRow(
                h3("Welcome"),
                p("Welcome to the test."),
                br(),
                actionButton("continue1", label = "weiter")
            )
        )
    ),
    
    hidden( 
        div(
            id = "instruction",
            mainPanel(
                fluidRow(
                    h3("Instruction"),
                    p("Please ...")),
                br(),
                actionButton("continue2", label = "weiter"))
        )
    ),
    
    hidden( 
        div(
            id = "IAT1",
            mainPanel(
                fluidRow(
                    h3("IAT"),
                    p("IAT word 1")),
                br(),
                tags$script('$(document).on("keypress", function(e) {
                            Shiny.onInputChange("keyid1", e.keyCode);
                            });'))
        ))
    
            )

server <- function(input, output,session) {
    observeEvent(input$continue1, {
        show("instruction")
        hide("welcome")
    })
    observeEvent(input$continue2, {
        show("IAT1")
        hide("instruction")
    })
    observeEvent(input$keyid1,{
        print(input$keyid1)
        if(input$keyid1 %in% c(101,105,69,73)) {
            hide("IAT1")  
            show("welcome")
        }
        else {}
    })
}

shinyApp(ui = ui, server = server)

Shiny Responds to Enter

In your case, the problem is reactive programming and this is the reason that you need something to manage this situation. My recommendation is to use observer pattern or validate function.

• Observer pattern: shiny implements the observer pattern which is
  useful to act when an event happens in an object (it can be a click
  in a button, new value in an input...).

• Validate function: the functionality of this process is similar to an
  if/else statement. Indeed, there is need what is the if to check the
  parameter, if the values are wrong, there will be an error message.

To know how to use observe pattern and the validate function, click on the previous link (in the Shiny website is everything explained).

R shiny addition of points according to input

Try this short and tidy server expression:

library (shiny)
library(shinyWidgets)
library(fresh)
library(htmltools)
ui<-navbarPage("Addition of points",
       tabPanel("Calculation",
                
                fluidPage(                            
                  headerPanel(h4("Scores")), 
                  headerPanel(h5("Please select your inputs.")),
                  
                  fluidRow(
                    (column (3, 
                             
                             headerPanel(h5(strong("Score1"))),
                             
                             sliderInput("score1", label = h6("Score1 (1-3), input <=2 should add 6 points to the total score, input >2 should add no points"), min = 1, max = 3, value = 1, ticks = TRUE, animate=TRUE, step = 1, width = "150px")                                      
                             
                    )),
                    (column (3,
                             
                             headerPanel(h5(strong("Score2"))),
                             
                             numericInput("score2", label = h6("Score2, input <=10 should add 5 points to the total score, input >10 should add no points"), value = "1" , width = "150px")
                             
                    )),
                    (column (3,
                             headerPanel(h5(strong("Score3"))),
                             radioButtons("score3", label = h6("Score3, clicking on 'No' should add 4 points to the total score, clicking on 'Yes' should add no points"), choices = list("No"=1, "Yes"=2), selected = character(0))
                             
                             
                    )),
                    (column (2,                                         
                             wellPanel(
                               style = "background: white", 
                               headerPanel(h4(strong("Score:"))),                                             
                               textOutput("multi")                                             
                             )))
                  )))
)
server<-function(input, output) {
    B <- reactive({
        0 + 
            (if(!is.null(input$score1) && input$score1<=2) 6 else 0) + 
            (if(!is.null(input$score2) && input$score2<=10) 5 else 0) +
            (if(!is.null(input$score3) && input$score3==1) 4 else 0)
    })
    output$multi <- renderText ({ B() })
}
shinyApp(ui, server)

R shiny: Add Konami Code inside a Shiny App

library(shiny)
runApp( list(ui = bootstrapPage(
  verbatimTextOutput("results"),
  verbatimTextOutput("allInputs"),
  tags$script('
              $(document).on("keypress", function (e) {
              Shiny.onInputChange("mydata", e.which);
              });
              ') 
)
, server = function(input, output, session) {

  output$results = renderPrint({
    input$mydata
  })

  keysPressed <- reactiveVal()

  observeEvent(input$mydata, {
    keysPressed(c(keysPressed(), input$mydata))
  })

  output$allInputs = renderPrint({
    keysPressed()
  })

}
))

ismirsehregal who helped me on the code I found

Is there a way in R shiny to concatenate all values taken by an input

My final code merging all hints:

UI.R (inside body)

          tags$script('
                   pressedKeyCount = 0;
                      $(document).on("keydown", function (e) {
                      Shiny.onInputChange("pressedKey", pressedKeyCount++);
                      Shiny.onInputChange("pressedKeyId", e.which);
                      });'
            ),

SERVER.R (somewhere)

keysPressed <- reactiveVal()

observeEvent(input$pressedKey, {
  keysPressed(c(keysPressed(), input$pressedKeyId))
})

output$secret <- renderUI({
  secretCode = keysPressed()
  if(length(secretCode)>=10)
  secretCode = secretCode[(length(secretCode)-9):length(secretCode)]
  trueCode = c(38,38,40,40,37,39,37,39,66,65)
  if(isTRUE(all.equal(secretCode,trueCode))){
    HTML('<center><img src="4BA140A6A75546D791B01BC0BA9E00A2.png"></center>')
    }
})

c(38,38,40,40,37,39,37,39,66,65) corresponds to famous konami code sequential key inputs

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