openPage: Open a new empty page

Description

openPage starts a server, establishes a web socket connection between it and the current R session and loads linked-charts JS library with all the dependencies. This function initializes an instance of class LCApp and stores it in the namespace of the package. If another instance has already been stored (i.e. another app has been started with this function), the existing app will be closed.

Usage

openPage(
  useViewer = TRUE,
  rootDirectory = NULL,
  startPage = NULL,
  layout = NULL,
  port = NULL,
  browser = NULL,
  onlyServer = FALSE,
  ...
)

Value

A new instance of class LCApp.

Arguments

useViewer: If TRUE, a page will be opened in the RStudio Viewer. If FALSE, a default web browser will be used.
rootDirectory: A path to the root directory for the server. Any file, requested by the server will be searched for in this directory. If rootDirectory is not defined, the http_root in the package directory will be used as a root directory.
startPage: A path to an HTML file that should be used as a starting page of the app. It can be an absolute path to a local file, or it can be relative to the rootDirectory or to the current R working directory. If startPage is not defined, an empty page will be used. The file must have .html extension.
layout: Adds one of the defaults layouts to each new page. Currently, only tables of arbitrary size are supported. To add a table, this parameter must be equal to "tableNxM", where N is the number of rows and M is the number of columns. Each cell will get an ID that consists of a letter (indicating the row) and a number (indicating the column) (e.g. B3 is an ID of the second row and third column).
port: Defines which TCP port the server will listen to. If not defined, random available port will be used (see randomPort).
browser: A browser in which to open a new web page. If not defined, default browser will be used. For more information check browseURL. If this argument is specified, useViewer will be ignored.
onlyServer: If TRUE, then an app will initialise without trying to open a new page in a browser.
...: Further arguments passed to openPage. Check details for more information.

Details

Argument onStart of jrc openPage function is replaced in rlc with beforeLoad and afterLoad. The reason for that is when the page opens, rlc has to put there all the existing charts. Different situations may require some code be loaded before or after that happens. beforeLoad and afterLoad provide a way to define two callback functions, each receiving a Session object as an argument and is called once for each new page. beforeLoad runs before anything else has happened, while afterLoad is called after all the existing charts have been added to the page.

This function initializes a new instance of class LCApp and wraps around methods startServer and openPage of its parent class App.

Examples

Run this code

if (FALSE) openPage()

openPage(useViewer = FALSE, layout = "table2x3")

Run the code above in your browser using DataLab