Change modal example

man/modalDialog.Rd

@@ -63,72 +63,61 @@ shinyApp(
 )
 
 
-# Display a modal that requires valid username and password input.
 shinyApp(
   ui = basicPage(
     actionButton("show", "Show modal dialog"),
-    verbatimTextOutput("loginInfo")
+    verbatimTextOutput("dataInfo")
   ),
+
   server = function(input, output) {
-    # A string with the current login status. This is in a reactiveValues
-    # object so that it can trigger reactivity.
-    vals <- reactiveValues(loginStatus = "Not logged in.")
+    # reactiveValues object for storing current data set.
+    vals <- reactiveValues(data = NULL)
 
-    # Attempt logging in with a username and password, returning TRUE if
-    # successful and FALSE if not.
-    login <- function(username, password) {
-      # In a real-world use case, this would check against some sort of user
-      # database instead of just checking that the values are identical to
-      # hard-coded values.
-      if (identical(username, "user1") && identical(password, "pass1")) {
-        vals$loginStatus <- paste0('Logged in as "', username, '"')
-        return(TRUE)
-
-      } else {
-        vals$loginStatus <- "Not logged in."
-        return(FALSE)
-      }
-    }
-
-    # Return the UI for a modal dialog with username/password inputs.
-    # If 'failed' is TRUE, then display a message that the previous username
-    # and password were invalid.
-    loginModal <- function(failed = FALSE) {
+    # Return the UI for a modal dialog with data selection input. If 'failed' is
+    # TRUE, then display a message that the previous value was invalid.
+    dataModal <- function(failed = FALSE) {
       modalDialog(
-        textInput("username", "Username"),
-        passwordInput("password", "Password"),
-        span('(Try logging in with "user1" and "pass1")'),
+        textInput("dataset", "Choose data set",
+          placeholder = 'Try "mtcars" or "abc"'
+        ),
+        span('(Try the name of a valid data object like "mtcars", then a name of a non-existent object like "abc")'),
         if (failed)
-          div(tags$b("Invalid username/password", style = "color: red;")),
+          div(tags$b("Invalid name of data object", style = "color: red;")),
 
         footer = tagList(
           modalButton("Cancel"),
-          actionButton("login", "Log in")
+          actionButton("ok", "OK")
         )
       )
     }
 
+    # Show modal when button is clicked.
     observeEvent(input$show, {
-      showModal(loginModal())
+      showModal(dataModal())
     })
 
-    # When login button is pressed, attempt to log in. If successful, remove the
-    # modal. If not show another modal, but this time with a failure message.
-    observeEvent(input$login, {
-      if (login(input$username, input$password)) {
+    # When OK button is pressed, attempt to load the data set. If successful,
+    # remove the modal. If not show another modal, but this time with a failure
+    # message.
+    observeEvent(input$ok, {
+      # Check that data object exists and is data frame.
+      if (exists(input$dataset) && is.data.frame(get(input$dataset))) {
+        vals$data <- get(input$dataset)
         removeModal()
       } else {
-        showModal(loginModal(failed = TRUE))
+        showModal(dataModal(failed = TRUE))
       }
     })
 
-    # Display current login status
-    output$loginInfo <- renderText({
-      vals$loginStatus
+    # Display information about selected data
+    output$dataInfo <- renderPrint({
+      if (is.null(vals$data))
+        "No data selected"
+      else
+        summary(vals$data)
     })
   }
 )
-
 }
 }