Skip to contents

Create a chat UI element

Source: R/chat.R
chat_ui.Rd

Inserts a chat UI element into a Shiny UI, which includes a scrollable section for displaying chat messages, and an input field for the user to enter new messages.

To respond to user input, listen for input$ID_user_input (for example, if id="my_chat", user input will be at input$my_chat_user_input), and use chat_append() to append messages to the chat.

Usage

chat_ui(
  id,
  ...,
  messages = NULL,
  placeholder = "Enter a message...",
  width = "min(680px, 100%)",
  height = "auto",
  fill = TRUE,
  icon_assistant = NULL
)

Arguments

id

The ID of the chat element

...

Extra HTML attributes to include on the chat element

messages

A list of messages to prepopulate the chat with. Each message can be one of the following:

  • A string, which is interpreted as markdown and rendered to HTML on the client.

  • A UI element.

    • This includes htmltools::tagList(), which take UI elements (including strings) as children. In this case, strings are still interpreted as markdown as long as they're not inside HTML.

  • A named list of content and role. The content can contain content as described above, and the role can be "assistant" or "user".

placeholder

The placeholder text for the chat's user input field

width

The CSS width of the chat element

height

The CSS height of the chat element

fill

Whether the chat element should try to vertically fill its container, if the container is fillable

icon_assistant

The icon to use for the assistant chat messages. Can be HTML or a tag in the form of htmltools::HTML() or htmltools::tags(). If None, a default robot icon is used.

Value

A Shiny tag object, suitable for inclusion in a Shiny UI

Examples

if (FALSE) { # interactive()
library(shiny)
library(bslib)
library(shinychat)

ui <- page_fillable(
  chat_ui("chat", fill = TRUE)
)

server <- function(input, output, session) {
  observeEvent(input$chat_user_input, {
    # In a real app, this would call out to a chat client or API,
    # perhaps using the 'ellmer' package.
    response <- paste0(
      "You said:\n\n",
      "<blockquote>",
      htmltools::htmlEscape(input$chat_user_input),
      "</blockquote>"
    )
    chat_append("chat", response)
    chat_append("chat", stream)
  })
}

shinyApp(ui, server)
}