R/visit_shiny.R

In visit: Vaccine Phase I Design with Simultaneous Evaluation of Immunogenicity and Toxicity

#' Run Web-Based \code{visit} application
#'
#' Call Shiny to run \code{visit} as a web-based application.
#'
#' @details
#'
#' A web browser will be brought up for users to access the GUI of \code{\link{visit}}.
#'
#' @examples
#' \dontrun{
#' vtShiny()}
#'
#' @export
#'
vtShiny <- function() {

    req.pkgs        <- c("shiny", "xtable", "knitr", "rmarkdown", "pander");
    chk.uninstalled <- sapply(req.pkgs, function(x) {!requireNamespace(x, quietly = TRUE)});
    chk.inx         <- which(chk.uninstalled);
    
    if (0 < length(chk.inx)) {
        msg <- paste("For the GUI to work, please install ",
        ifelse(1 < length(chk.inx), "packages ", "package "),
        paste(req.pkgs[chk.inx], collapse = ", "),
        " by \n install.packages(",
        paste(paste("'", req.pkgs[chk.inx], "'", sep = ""), collapse = ", "),
        ") \n  ",
        sep = "");
        stop(msg, call. = FALSE);
    }
    
    
    appDir <- system.file("shiny", package = "visit")
    if (appDir == "") {
        stop("Could not find Shiny directory. Try re-installing `visit`.",
        call. = FALSE)
    }
    
    
    shiny::runApp(appDir, display.mode = "normal");
}