Add Conditional Separators (horizontal line or padding) to flextable Rows — add_flextable

Modifies an existing flextable object by adding visual separators (horizontal lines or bottom padding) after specific rows based on a control vector, without changing the table's row count.

Usage

add_flextable_separators(
  ft,
  trailing_sep,
  border = officer::fp_border(width = 1, color = "grey60"),
  padding = 10
)

Arguments

ft: A flextable object.
trailing_sep: A vector specifying separators. Its length must equal the number of rows in the body of ft. Allowed values are NA (no separator), "-" (adds a horizontal line), or " " (adds bottom padding).
border: The fp_border object to use for horizontal lines when trailing_sep is "-". Defaults to a gray line of width 1.
padding: The amount of bottom padding (in points) to add when trailing_sep is " ". Defaults to 10.

Value

The modified flextable object, or the original ft if all trailing_sep values are NA. Throws an error for invalid inputs or invalid characters in trailing_sep.

Examples

content <- data.frame(
  USUBJID = c("S1", "S1", "S1", "S2", "S2", "S2", "S3"),
  ARM = c("A", "A", "B", "A", "A", "B", "A"),
  VAL = round(rnorm(7), 2)
)
ft <- flextable::as_flextable(content)
ft <- flextable::theme_booktabs(ft)

# Define separators: line, space, NA, line, space, NA, NA
sep_ctrl <- c("-", " ", NA, "-", " ", NA, NA)

ft_modified <- add_flextable_separators(ft, sep_ctrl)
print(ft_modified)
#> <style></style>
#> <div class="tabwid"><style>.cl-01dd5b08{}.cl-01d66c94{font-family:'DejaVu Sans';font-size:11pt;font-weight:normal;font-style:normal;text-decoration:none;color:rgba(0, 0, 0, 1.00);background-color:transparent;}.cl-01d66c9e{font-family:'DejaVu Sans';font-size:11pt;font-weight:normal;font-style:normal;text-decoration:none;color:rgba(153, 153, 153, 1.00);background-color:transparent;}.cl-01d8f360{margin:0;text-align:left;border-bottom: 0 solid rgba(0, 0, 0, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);padding-bottom:5pt;padding-top:5pt;padding-left:5pt;padding-right:5pt;line-height: 1;background-color:transparent;}.cl-01d8f374{margin:0;text-align:right;border-bottom: 0 solid rgba(0, 0, 0, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);padding-bottom:5pt;padding-top:5pt;padding-left:5pt;padding-right:5pt;line-height: 1;background-color:transparent;}.cl-01d8f375{margin:0;text-align:left;border-bottom: 0 solid rgba(0, 0, 0, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);padding-bottom:10pt;padding-top:5pt;padding-left:5pt;padding-right:5pt;line-height: 1;background-color:transparent;}.cl-01d8f37e{margin:0;text-align:right;border-bottom: 0 solid rgba(0, 0, 0, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);padding-bottom:10pt;padding-top:5pt;padding-left:5pt;padding-right:5pt;line-height: 1;background-color:transparent;}.cl-01d91034{width:1.017in;background-color:transparent;vertical-align: middle;border-bottom: 0 solid rgba(102, 102, 102, 1.00);border-top: 1.5pt solid rgba(102, 102, 102, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d9103e{width:0.911in;background-color:transparent;vertical-align: middle;border-bottom: 0 solid rgba(102, 102, 102, 1.00);border-top: 1.5pt solid rgba(102, 102, 102, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d9103f{width:1.017in;background-color:transparent;vertical-align: middle;border-bottom: 1.5pt solid rgba(102, 102, 102, 1.00);border-top: 0 solid rgba(102, 102, 102, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91048{width:0.911in;background-color:transparent;vertical-align: middle;border-bottom: 1.5pt solid rgba(102, 102, 102, 1.00);border-top: 0 solid rgba(102, 102, 102, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91049{width:1.017in;background-color:transparent;vertical-align: middle;border-bottom: 1pt solid rgba(153, 153, 153, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91052{width:0.911in;background-color:transparent;vertical-align: middle;border-bottom: 1pt solid rgba(153, 153, 153, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91053{width:1.017in;background-color:transparent;vertical-align: middle;border-bottom: 0 solid rgba(0, 0, 0, 1.00);border-top: 1pt solid rgba(153, 153, 153, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d9105c{width:0.911in;background-color:transparent;vertical-align: middle;border-bottom: 0 solid rgba(0, 0, 0, 1.00);border-top: 1pt solid rgba(153, 153, 153, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d9105d{width:1.017in;background-color:transparent;vertical-align: middle;border-bottom: 0 solid rgba(0, 0, 0, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91066{width:0.911in;background-color:transparent;vertical-align: middle;border-bottom: 0 solid rgba(0, 0, 0, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91067{width:1.017in;background-color:transparent;vertical-align: middle;border-bottom: 1.5pt solid rgba(102, 102, 102, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91070{width:0.911in;background-color:transparent;vertical-align: middle;border-bottom: 1.5pt solid rgba(102, 102, 102, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91071{width:1.017in;background-color:transparent;vertical-align: middle;border-bottom: 1.5pt solid rgba(102, 102, 102, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}.cl-01d91072{width:0.911in;background-color:transparent;vertical-align: middle;border-bottom: 1.5pt solid rgba(102, 102, 102, 1.00);border-top: 0 solid rgba(0, 0, 0, 1.00);border-left: 0 solid rgba(0, 0, 0, 1.00);border-right: 0 solid rgba(0, 0, 0, 1.00);margin-bottom:0;margin-top:0;margin-left:0;margin-right:0;}</style><table data-quarto-disable-processing='true' class='cl-01dd5b08'><thead><tr style="overflow-wrap:break-word;"><th class="cl-01d91034"><p class="cl-01d8f360"><span class="cl-01d66c94">USUBJID</span></p></th><th class="cl-01d91034"><p class="cl-01d8f360"><span class="cl-01d66c94">ARM</span></p></th><th class="cl-01d9103e"><p class="cl-01d8f374"><span class="cl-01d66c94">VAL</span></p></th></tr><tr style="overflow-wrap:break-word;"><th class="cl-01d9103f"><p class="cl-01d8f360"><span class="cl-01d66c9e">character</span></p></th><th class="cl-01d9103f"><p class="cl-01d8f360"><span class="cl-01d66c9e">character</span></p></th><th class="cl-01d91048"><p class="cl-01d8f374"><span class="cl-01d66c9e">numeric</span></p></th></tr></thead><tbody><tr style="overflow-wrap:break-word;"><td class="cl-01d91049"><p class="cl-01d8f360"><span class="cl-01d66c94">S1</span></p></td><td class="cl-01d91049"><p class="cl-01d8f360"><span class="cl-01d66c94">A</span></p></td><td class="cl-01d91052"><p class="cl-01d8f374"><span class="cl-01d66c94">-1.4</span></p></td></tr><tr style="overflow-wrap:break-word;"><td class="cl-01d91053"><p class="cl-01d8f375"><span class="cl-01d66c94">S1</span></p></td><td class="cl-01d91053"><p class="cl-01d8f375"><span class="cl-01d66c94">A</span></p></td><td class="cl-01d9105c"><p class="cl-01d8f37e"><span class="cl-01d66c94">0.3</span></p></td></tr><tr style="overflow-wrap:break-word;"><td class="cl-01d9105d"><p class="cl-01d8f360"><span class="cl-01d66c94">S1</span></p></td><td class="cl-01d9105d"><p class="cl-01d8f360"><span class="cl-01d66c94">B</span></p></td><td class="cl-01d91066"><p class="cl-01d8f374"><span class="cl-01d66c94">-2.4</span></p></td></tr><tr style="overflow-wrap:break-word;"><td class="cl-01d91049"><p class="cl-01d8f360"><span class="cl-01d66c94">S2</span></p></td><td class="cl-01d91049"><p class="cl-01d8f360"><span class="cl-01d66c94">A</span></p></td><td class="cl-01d91052"><p class="cl-01d8f374"><span class="cl-01d66c94">-0.0</span></p></td></tr><tr style="overflow-wrap:break-word;"><td class="cl-01d91053"><p class="cl-01d8f375"><span class="cl-01d66c94">S2</span></p></td><td class="cl-01d91053"><p class="cl-01d8f375"><span class="cl-01d66c94">A</span></p></td><td class="cl-01d9105c"><p class="cl-01d8f37e"><span class="cl-01d66c94">0.6</span></p></td></tr><tr style="overflow-wrap:break-word;"><td class="cl-01d9105d"><p class="cl-01d8f360"><span class="cl-01d66c94">S2</span></p></td><td class="cl-01d9105d"><p class="cl-01d8f360"><span class="cl-01d66c94">B</span></p></td><td class="cl-01d91066"><p class="cl-01d8f374"><span class="cl-01d66c94">1.1</span></p></td></tr><tr style="overflow-wrap:break-word;"><td class="cl-01d91067"><p class="cl-01d8f360"><span class="cl-01d66c94">S3</span></p></td><td class="cl-01d91067"><p class="cl-01d8f360"><span class="cl-01d66c94">A</span></p></td><td class="cl-01d91070"><p class="cl-01d8f374"><span class="cl-01d66c94">-1.8</span></p></td></tr></tbody><tfoot><tr style="overflow-wrap:break-word;"><td  colspan="3"class="cl-01d91071"><p class="cl-01d8f360"><span class="cl-01d66c94">n: 7</span></p></td></tr></tfoot></table></div>

# Example: All NA - should return original ft
ft_all_na <- add_flextable_separators(ft, rep(NA, 7))
identical(ft, ft_all_na) # Should be TRUE
#> [1] TRUE

# Example: Invalid character - should throw error
tryCatch(
  add_flextable_separators(ft, c("-", "x", NA, "-", " ", NA, NA)),
  error = function(e) print(e)
)
#> <simpleError in add_flextable_separators(ft, c("-", "x", NA, "-", " ", NA, NA)): Invalid character(s) found as trailing separators: 'x'. Only NA (no sparator), '-' (a line), or ' ' (padding) are allowed.>