Allow fill_color arg in fmt_icon() to use of named vector/list

R/format_data.R

@@ -11135,13 +11135,16 @@ fmt_country <- function(
 #'
 #' @param fill_color *Color of the icon fill*
 #'
-#'   `scalar<character>` // *default:* `NULL` (`optional`)
+#'   `scalar<character>|vector<character>` // *default:* `NULL` (`optional`)
 #'
 #'   The fill color of the icon can be set with `fill_color`; providing a single
 #'   color here will change the color of the fill but not of the icon's 'stroke'
-#'   or outline (use `stroke_color` to modify that). If not provided then the
-#'   default value of `"currentColor"` is applied so that the fill matches the
-#'   color of the parent HTML element's color attribute.
+#'   or outline (use `stroke_color` to modify that). A named vector or named
+#'   list comprising the icon names with corresponding fill colors can
+#'   alternatively be used here (e.g.,
+#'   `list("circle-check" = "green", "circle-xmark" = "red"`). If nothing is
+#'   provided then the default value of `"currentColor"` is applied so that the
+#'   fill matches the color of the parent HTML element's color attribute.
 #'
 #' @param fill_alpha *Transparency value for icon fill*
 #'
@@ -11416,6 +11419,45 @@ fmt_country <- function(
 #' `r man_get_image_tag(file = "man_fmt_icon_4.png")`
 #' }}
 #'
+#' A fairly common thing to do with icons in tables is to indicate whether
+#' a quantity is either higher or lower than another. Up and down arrow symbols
+#' can serve as good visual indicators for this purpose. We can make use of the
+#' `"up-arrow"` and `"down-arrow"` icons here. The `fmt_icon()` function has to
+#' find those text values in cells to generate the icons, so, lets generate the
+#' text within a new column via the [cols_add()] function (an expression is used
+#' therein to generate the correct text given the `close` and `open` values).
+#' Following that, `fmt_icon()` is used and its `fill_color` argument is
+#' provided with a named vector that indicates which color should be used for
+#' each icon.
+#'
+#' ```r
+#' sp500 |>
+#'   dplyr::slice_head(n = 10) |>
+#'   dplyr::select(date, open, close) |>
+#'   dplyr::arrange(-dplyr::row_number()) |>
+#'   gt(rowname_col = "date") |>
+#'   cols_add(week = date, .after = date) |>
+#'   cols_add(dir = ifelse(close > open, "arrow-up", "arrow-down")) |>
+#'   cols_merge(columns = c(date, week), pattern = "{1} ({2})") |>
+#'   fmt_date(columns = date, date_style = "m_day_year") |>
+#'   fmt_datetime(columns = week, format = "w", pattern = "W{x}") |>
+#'   fmt_currency() |>
+#'   fmt_icon(
+#'     columns = dir,
+#'     fill_color = c("arrow-up" = "green", "arrow-down" = "red")
+#'   ) |>
+#'   cols_label(
+#'     open = "Opening Value",
+#'     close = "Closing Value",
+#'     dir = ""
+#'   ) |>
+#'   opt_stylize(style = 1, color = "gray")
+#' ```
+#'
+#' \if{html}{\out{
+#' `r man_get_image_tag(file = "man_fmt_icon_5.png")`
+#' }}
+#'
 #' @family data formatting functions
 #' @section Function ID:
 #' 3-24
@@ -11567,6 +11609,8 @@ fmt_icon <- function(
 
         x_str_non_missing <- x[!is.na(x)]
 
+        fill_color_named <- rlang::is_named(fill_color)
+
         x_str_non_missing <-
           vapply(
             seq_along(x_str_non_missing),
@@ -11593,11 +11637,22 @@ fmt_icon <- function(
 
               for (y in seq_along(icons)) {
 
+                icon_name_i <- icons[y]
+
+                if (
+                  fill_color_named &&
+                  rlang::has_name(fill_color, name = icon_name_i)
+                ) {
+                  fill_color_i <- fill_color[[icon_name_i]]
+                } else {
+                  fill_color_i <- fill_color
+                }
+
                 out_y <-
                   as.character(
                     fontawesome::fa(
                       name = icons[y],
-                      fill = fill_color,
+                      fill = fill_color_i,
                       fill_opacity = fill_alpha,
                       stroke = stroke_color,
                       stroke_width = stroke_width,