Allowing chunks for ref_symbol in footnote to change colors

[hennerw]

Hello,

I was trying to color the reference tags when using footnote and was unable to find a way to do it. Looking at the footnote function, it expects a character vector for ref_symbol, but then converts that to a chunk when applying superscript to it.

By converting it to a chunk earlier, if it is not already, I can fairly easily pass chunks in with any of their normal formatting options. Just need to update the references from vector to rows of the chunk.

Here's a working example, though I have not messed with inline or completely checked the warning message/checks. It will now just pass through chunk options. Is this something that would be reasonable to implement? I am not really adept at formatting chunks, so I am not sure if this would cause more difficulties or issues elsewhere.

Refs <- as_chunk(LETTERS[1:2],props = fp_text_default(color = 'orange'))

iris[1:4,] %>%
  flextable() %>%
  footnote3(i=1:2,j=1,ref_symbols = Refs, value = as_paragraph(c("Example footnote 1","Example footnote 2")))

With the updated function:

footnote3 <- function(x, i = NULL, j = NULL, value, ref_symbols = NULL, part = "body",

                     inline = FALSE, sep = "; ") {

  if (!inherits(x, "flextable")) {

    stop(sprintf("Function `%s` supports only flextable objects.", "footnote()"))

  }

  if (!inherits(value, "paragraph")) {

    stop("`value` must be a paragraph.")

  }

 

  part <- match.arg(part, c("body", "header", "footer"),

                    several.ok = FALSE

  )

 

  if (nrow_part(x, part) < 1) {

    return(x)

  }

 

  flextable:::check_formula_i_and_part(i, part)

  i <- flextable:::get_rows_id(x[[part]], i)

  j <- flextable:::get_columns_id(x[[part]], j)

 

  if (is.null(ref_symbols)) {

    symbols_str <- as.character(seq_along(value))

  } else {

    symbols_str <- ref_symbols

  }

 

  if (any(symbols_str %in% "")) {

    long_msg <- c(

      "Usage of empty symbol '' with footnote should not happen, ",

      "use `add_footer_lines()` instead, it does not require any symbol. ",

      "This usage will be forbidden in the next release. Please, wait for 10 seconds!"

    )

    long_msg <- paste0(long_msg, collapse = "\n")

    message(long_msg)

    Sys.sleep(10)

  }

 

  sep_str <- rep(sep, length(value))

 

  cell_index <- data.frame(i = i, j = j)

  if (length(symbols_str) == 1) {

    symbols_str <- rep(symbols_str, nrow(cell_index))

  }

 

  if(!any(class(ref_symbols) == 'chunk')){

    symbols_str <- as_chunk(symbols_str)

  }

 

  # Assert that either one footnote, or that footnote symbol length matches number

  # of cells to tag

  stopifnot(nrow(symbols_str) == nrow(cell_index))

 

  for (index_num in seq_len(nrow(cell_index))) {

    i_cell <- cell_index[["i"]][index_num]

    j_cell <- cell_index[["j"]][index_num]

    x <- append_chunks(x,

                       i = i_cell, j = j_cell,

                       part = part,

                       as_sup(symbols_str[index_num,])

    )

  }

 

  if (inline) {

    # init a new line

    if (nrow_part(x, "footer") < 1) {

      x <- add_footer_lines(x, values = "")

      n_row <- 1

    } else {

      n_row <- nrow_part(x, "footer")

      target_par <- get_fpstruct_elements(

        x = x[["footer"]]$content,

        i = n_row,

        j = 1)[[1,1]]

    }

   

    paras <- mapply(rbind,

                    as_paragraph(as_sup(ref_symbols)),

                    value,

                    as_paragraph(sep_str),

                    SIMPLIFY = FALSE

    )

    paras <- rbind_match_columns(paras)

    paras$.chunk_index <- NULL

    for(i in seq_len(nrow(paras))) {

      x[["footer"]]$content <-

        append_chunkset_struct_element(

          x = x[["footer"]]$content,

          i = n_row,

          j = 1,

          chunk_data = paras[i,]

        )

    }

  } else {

    # init new lines

    n_row <- nrow_part(x, "footer")

    x <- add_footer_lines(x, values = rep("", length(value)))

    newcontent <- flextable:::as_chunkset_struct(

      l_paragraph = value, keys = x$col_keys[1])

    x[["footer"]]$content <- flextable:::set_chunkset_struct_element(

      x = x[["footer"]]$content,

      i = n_row + seq_along(value), j = 1,

      value = newcontent

    )

    for (v in seq_along(value)) {

      x <- prepend_chunks(

        x = x, i = n_row + v, j = 1,

        part = "footer",

        as_sup(symbols_str[v,])

      )

    }

  }

  x

}