Add a reset button to trigger the recieveMessage() method

inst/shiny-input-app/app.R

@@ -23,11 +23,16 @@ typingSpeedInput <- function(inputId, label, placeholder = NULL) {
 ui <- fluidPage(
   # textAreaInput("typing", "Type here..."),
   typingSpeedInput("typing", "Type here..."),
+  actionButton("reset", "Reset"),
   verbatimTextOutput("debug")
 )
 
 server <- function(input, output, session) {
   output$debug <- renderPrint(input$typing)
+
+  observeEvent(input$reset, {
+    session$sendInputMessage("typing", TRUE)
+  })
 }
 
 shinyApp(ui, server)

inst/shiny-input-app/dev-shiny-input.Rmd

@@ -454,3 +454,16 @@ Try various settings of
 
 Find a good delay rate.
 
+### Almost done: Implement `receiveMessage()`
+
+There's not much we'd want to do from the server side
+in terms of updating the typing area.
+But maybe we'd like to be able to add a "Reset" button.
+
+Write a method that,
+when it recieves a `true` value from the server,
+clears the text input area.
+
+Add a reset button to your app that uses `shiny$sendInputMessage()`
+to send `typing` a `TRUE`
+whenever the button is clicked.

inst/shiny-input-app/typing.js

@@ -53,10 +53,12 @@ $.extend(typingSpeed, {
     // and its elements to reflect the given data.
     // The messages are sent from R/Shiny via
     // R> session$sendInputMessage(inputId, data)
-    console.error('typingSpeed.receiveMessage() is not yet defined');
 
     // If you want the update to trigger reactivity, trigger a subscribed event
-    // $(el).trigger("keyup")
+    if (typeof data === 'boolean' && data) {
+      el.value = ''
+      $(el).trigger('keyup')
+    }
   },
   subscribe: function(el, callback) {
     // Listen to events on your input element. The following block listens to