R/add_custom_style.R

In johnaclouse/curios: Curios Used in Support of Practical Data Science

#' Include Custom HTML Style Elements Into Active Document
#'
#' Generate inline style components to modify the standard flexdashboard
#' \emph{css}. Original functionality updated based on example from
#' \code{st_css()} from \url{https://github.com/dcomtois/summarytools}
#'
#' @details The style formatting is intended to be used with bootsrap's
#'   \code{readable} theme.
#'
#' @param main Logical. Include \emph{summarytools.css} file. \code{TRUE} by
#'   default. This will affects only \strong{summarytools} objects, for one
#'   exception: two properties of the \code{img} tag are redefined to have
#'   \code{background-color: transparent} and \code{border: 0}.
#' @param \dots Character. Path to additional \emph{css} file(s) to include.
#'
#' @return The style content and \emph{css} file(s) returned silently as a
#'   character vector, and printed (using \code{cat()}).
#'
#' @details The function may be called in an \emph{R markdown} document code
#'   chunk having options \code{echo=FALSE} and \code{results="asis"}.
#'
#' @export
add_custom_style <- function(main = TRUE,
                             ...) {

  output <- character()

  output <- append(output, "<style type=\"text/css\">\n")

  if (isTRUE(main)) {
    output <- append(output, "/* Overwrite flexdashboard readable theme */
    body {
    background: #ffffff;
    }

    .navbar-brand  {
    /* align flexdashboard title (aka brand) with logo */
    padding: 15px 0px 0px 15px;
    }

    pre {
    background-color:white; border:0; /* background for sidebar*/
    }

    /* Adjust ### headers created in flexdashboard */
    .chart-title {
    /* border-bottom: 1px solid #d7d7d7; */
    border-bottom: none;
    color: #000000;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 22px;
    font-weight: 700;
    padding: 7px 0px 0px 7px;
    margin-top: 60px; /* fixes relative link landing on page and hiding heading*/
    }

    /* Remove border around section level 3 content */
    .chart-wrapper {
    border-style: none;
    }


    /* Adjust #### headers created in flexdashboard */
    h4 {
    /* border-bottom: 1px solid #d7d7d7; */
    border-bottom: none;
    color: #505050;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 18px;
    font-weight: 600;
    padding: 75px 0px 0px 7px;
    margin-top: -10px; /* fixes relative link landing on page and hiding heading*/
    }


    /* Adjust ##### headers created in flexdashboard */
    h5 {
    /* border-bottom: 1px solid #d7d7d7; */
    border-bottom: none;
    color: #808080;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 16px;
    font-weight: 500;
    padding: 16px 0px 0px 14px;
    }

    p {
    padding: 0px 0px 0px 20px;
    }

    a:link {
    color: blue;
    }

    a:visited {
    color: blue;
    }

    .table {
    margin-left: 100px
    }


    .table>thead>tr>th {
    border-color: black;
    }


    /* Remove borders within the table body */
    .table>tbody>tr>td {
    border: none;
    }


    /* Add a top border to the table header row */
    .table thead tr:first-child {
    border-top: 2px solid black;
    }


    /* Add a bottom border to the table body
    .table tbody tr:last-child {
    border-bottom: 2px solid black;
    }
    */

    /* Make the table header row a normal weight; not bold */
    .table th{
    font-weight: normal;
    }


    /* Make the caption italic and black */
    .table caption{
    font-style: italic;
    color: black;
    }

    .image-container {
    background-position: center top !important;
    }

    .scroll_chunk {
    max-height: 425px;
    float: left;
    overflow-y: auto;
    }

    mark {
    background-color: yellow;
    color: black;
    }")
  }


  dotArgs <- list(...)
  for (f in dotArgs) {
    output <- append(output, readLines(f))
  }

  output <- append(output, "</style>\n")

  output <- paste(output, sep = "\n")
  cat(output)
  return(invisible(output))
}