Display a popup message (modal) in Shiny

Description

A modal can contain text, images, OK/Cancel buttons, an input to get a response from the user, and many more customizable options. The value of the modal can be retrieved in Shiny using input$shinyalert or using the two callback parameters. See the demo Shiny app online for examples or read the full README.

shinyalert must be initialized with a call to useShinyalert in the app's UI.

Usage

shinyalert(title = "", text = "", type = "", closeOnEsc = TRUE,
  closeOnClickOutside = FALSE, html = FALSE, showCancelButton = FALSE,
  showConfirmButton = TRUE, inputType = "text", inputValue = "",
  inputPlaceholder = "", confirmButtonText = "OK",
  confirmButtonCol = "#AEDEF4", cancelButtonText = "Cancel", timer = 0,
  animation = TRUE, imageUrl = NULL, imageWidth = 100,
  imageHeight = 100, className = "", callbackR = NULL,
  callbackJS = NULL)

Arguments

Input modals

Usually the purpose of a modal is simply informative, to show some information to the user. However, the modal can also be used to retrieve an input from the user by setting the type = "input" parameter.

Only a single input can be used inside a modal. By default, the input will be a text input, but you can use other HTML input types by specifying the inputType parameter. For example, inputType = "number" will provide the user with a numeric input in the modal.

See the 'Modal return value' and 'Callbacks' sections below for information on how to access the value entered by the user.

Modal return value

Modals created with shinyalert have a return value when they exit.

When there is an input field in the modal (type="input"), the value of the modal is the value the user entered. When there is no input field in the modal, the value of the modal is TRUE if the user clicked the "OK" button, and FALSE if the user clicked the "Cancel" button.

When the user exits the modal using the Escape key or by clicking outside of the modal, the return value is FALSE (as if the "Cancel" button was clicked). If the timer parameter is used and the modal closes automatically as a result of the timer, no value is returned from the modal.

The return value of the modal can be accessed via input$shinyalert in the Shiny server's code, as if it were a regular Shiny input. The return value can also be accessed using the modal callbacks (see below).

Callbacks

The return value of the modal is passed as an argument to the callbackR and callbackJS functions (if a callbackR or callbackJS arguments are provided). These are functions that get called, either in R or in JavaScript, when the modal exits.

For example, using the following shinyalert code will result in a modal with an input field. After the user clicks "OK", a hello message will be printed to both the R console and in a native JavaScript alert box. You don't need to provide both callback functions, but in this example both are used for demonstration.

  shinyalert(
    "Enter your name", type = "input",
    callbackR = function(x) { message("Hello ", x) },
    callbackJS = "function(x) { alert('Hello ' + x); }"
  )

Notice that the callbackR function accepts R code, while the callbackJS function uses JavaScript code.

Since closing the modal with the Escape key results in a return value of FALSE, the callback functions can be modified to not print hello in that case.

  shinyalert(
    "Enter your name", type = "input",
    callbackR = function(x) { if(x != FALSE) message("Hello ", x) },
    callbackJS = "function(x) { if (x !== false) { alert('Hello ' + x); } }"
  )

See Also

useShinyalert

Examples

if (interactive()) {
  library(shiny)
  library(shinyalert)

  shinyApp(
    ui = fluidPage(
      useShinyalert(),  # Set up shinyalert
      actionButton("btn", "Click me")
    ),
    server = function(input, output) {
      observeEvent(input$btn, {
        # Show a simple modal
        shinyalert(title = "You did it!", type = "success")
      })
    }
  )
}