Format email addresses to generate 'mailto:' links

Should cells contain email addresses, fmt_email() can be used to make email addresses work well with email clients on the user system. This should be expressly used on columns that contain only email addresses (i.e., no email addresses as part of a larger block of text). Should you have such a column of data, there are options for how the email addresses should be styled. They can be of the conventional style (with underlines and text coloring that sets it apart from other text), or, they can appear to be button-like (with a surrounding box that can be filled with a color of your choosing).

Email addresses in data cells are trusted as email addresses. We can also provide more readable labels with the display_name argument. Supplying a single value there will show the same label for all email addresses but display names from an adjacent column could be used via a from_column() call within display_name.

Usage

fmt_email(
  data,
  columns = everything(),
  rows = everything(),
  display_name = NULL,
  as_button = FALSE,
  color = "auto",
  show_underline = "auto",
  button_fill = "auto",
  button_width = "auto",
  button_outline = "auto",
  target = NULL
)

Arguments

data

The gt table data object

obj:<gt_tbl> // required

This is the gt table object that is commonly created through use of the gt() function.

columns

Columns to target

<column-targeting expression> // default: everything()

Can either be a series of column names provided in c(), a vector of column indices, or a select helper function (e.g. starts_with(), ends_with(), contains(), matches(), num_range() and everything()).

rows

Rows to target

<row-targeting expression> // default: everything()

In conjunction with columns, we can specify which of their rows should undergo formatting. The default everything() results in all rows in columns being formatted. Alternatively, we can supply a vector of row captions within c(), a vector of row indices, or a select helper function (e.g. starts_with(), ends_with(), contains(), matches(), num_range(), and everything()). We can also use expressions to filter down to the rows we need (e.g., [colname_1] > 100 & [colname_2] < 50).

display_name

Display name for the email address

scalar<character> // default: NULL (optional)

The display name is the visible 'label' to use for the email address. If NULL (the default) the address itself will serve as the display name. There are two non-NULL options: (1) a piece of static text can be used for the display name by providing a string, and (2) a function can be provided to fashion a display name from every email address.

as_button

Style email address as a button

scalar<logical> // default: FALSE

An option to style the email address as a button. By default, this is FALSE. If this option is chosen then the button_fill argument becomes usable.

color

Link color

scalar<character> // default: "auto"

The color used for the resulting email address and its underline. This is "auto" by default; this allows gt to choose an appropriate color based on various factors (such as the background button_fill when as_button is TRUE).

show_underline

Show the link underline

scalar<character>|scalar<logical> // default: "auto"

Should the email address be decorated with an underline? By default this is "auto" which means that gt will choose TRUE when as_button = FALSE and FALSE in the other case. The underline will be the same color as that set in the color option.

button_fill, button_width, button_outline

Button options

scalar<character> // default: "auto"

Options for styling an email address as a button (and only applies if as_button = TRUE). All of these options are by default set to "auto", allowing gt to choose appropriate fill, width, and outline values.

target

The 'target' anchor element attribute

scalar<character> // default: NULL

The anchor element 'target' attribute value. For a description of the 'target' attribute and its allowed values, refer to the MDN Web Docs reference on the anchor HTML element.

Value

An object of class gt_tbl.

Compatibility of formatting function with data values

fmt_email() is compatible with body cells that are of the "character" or "factor" types. Any other types of body cells are ignored during formatting. This is to say that cells of incompatible data types may be targeted, but there will be no attempt to format them.

Compatibility of arguments with the `from_column()` helper function

from_column() can be used with certain arguments of fmt_email() to obtain varying parameter values from a specified column within the table. This means that each row could be formatted a little bit differently. These arguments provide support for from_column():

display_name
as_button
color
show_underline
button_fill
button_width
button_outline

Please note that for each of the aforementioned arguments, a from_column() call needs to reference a column that has data of the correct type (this is different for each argument). Additional columns for parameter values can be generated with cols_add() (if not already present). Columns that contain parameter data can also be hidden from final display with cols_hide(). Finally, there is no limitation to how many arguments the from_column() helper is applied so long as the arguments belong to this closed set.

Examples

Let's take ten rows from the peeps dataset and create a table of contact information with mailing addresses and email addresses. With the column that contains email addresses (email_addr), we can use fmt_email() to generate 'mailto:' links. Clicking any of these formatted email addresses should result in new message creation (depending on the OS integration with an email client).

peeps |>
  dplyr::filter(country == "AUS") |>
  dplyr::select(
    starts_with("name"),
    address, city, state_prov, postcode, country, email_addr
  ) |>
  dplyr::mutate(city = toupper(city)) |>
  gt(rowname_col = "name_family") |>
  tab_header(title = "Our Contacts in Australia") |>
  tab_stubhead(label = "Name") |>
  fmt_email(columns = email_addr) |>
  fmt_country(columns = country) |>
  cols_merge(
    columns = c(address, city, state_prov, postcode, country),
    pattern = "{1}<br>{2} {3} {4}<br>{5}"
  ) |>
  cols_merge(
    columns = c(name_family, name_given),
    pattern = "{1},<br>{2}"
  ) |>
  cols_label(
    address = "Mailing Address",
    email_addr = "Email"
  ) |>
  tab_style(
    style = cell_text(size = "x-small"),
    locations = cells_body(columns = address)
  ) |>
  opt_align_table_header(align = "left")

This image of a table was generated from the first code example in the `fmt_email()` help file.

We can further condense the table by reducing the email link to an icon. The approach we take here is the use of a fontawesome icon within the display_name argument. The icon used is "envelope" and each icon produced serves as a clickable 'mailto:' link. By adjusting one of the cols_merge() calls, we can place the icon/link next to the name of the person.

peeps |>
  dplyr::filter(country == "AUS") |>
  dplyr::select(
    starts_with("name"),
    address, city, state_prov, postcode, country, email_addr
  ) |>
  dplyr::mutate(city = toupper(city)) |>
  gt(rowname_col = "name_family") |>
  tab_header(title = "Our Contacts in Australia") |>
  fmt_email(
    columns = email_addr,
    display_name = fontawesome::fa(
      name = "envelope",
      height = "0.75em",
      fill = "gray"
    )
  ) |>
  fmt_country(columns = country) |>
  cols_merge(
    columns = c(address, city, state_prov, postcode, country),
    pattern = "{1}<br>{2} {3} {4}<br>{5}"
  ) |>
  cols_merge(
    columns = c(name_family, name_given, email_addr),
    pattern = "{1}, {2} {3}"
  ) |>
  cols_width(everything() ~ px(200)) |>
  tab_style(
    style = cell_text(size = px(11)),
    locations = cells_body(columns = address)
  ) |>
  tab_options(column_labels.hidden = TRUE) |>
  opt_align_table_header(align = "left")

This image of a table was generated from the second code example in the `fmt_email()` help file.

Another option is to display the names of the email recipients instead of the email addresses, making the display names serve as 'mailto:' links. We can do this by using from_column() in the display_name argument. The display names in this case are the combined given and family names, handled earlier through a dplyr::mutate() call. With some space conserved, we take the opportunity here to add in phone information for each person.

peeps |>
  dplyr::filter(country == "AUS") |>
  dplyr::mutate(name = paste(name_given, name_family)) |>
  dplyr::mutate(city = toupper(city)) |>
  dplyr::mutate(phone_number = gsub("^\\(0|\\)", "", phone_number)) |>
  dplyr::select(
    name, address, city, state_prov, postcode, country,
    email_addr, phone_number, country_code
  ) |>
  gt(rowname_col = "email_addr") |>
  tab_header(title = "Our Contacts in Australia") |>
  tab_stubhead(label = "Name") |>
  fmt_email(
    columns = email_addr,
    display_name = from_column("name"),
    color = "gray25"
  ) |>
  cols_hide(columns = name) |>
  fmt_country(columns = country) |>
  cols_merge(
    columns = c(address, city, state_prov, postcode, country),
    pattern = "{1}<br>{2} {3} {4}<br>{5}"
  ) |>
  cols_merge(
    columns = c(phone_number, country_code),
    pattern = "+{2} {1}"
  ) |>
  cols_label(
    address = "Mailing Address",
    email_addr = "Email",
    phone_number = "Phone"
  ) |>
  cols_move_to_start(columns = phone_number) |>
  cols_width(everything() ~ px(170)) |>
  tab_style(
    style = cell_text(size = px(11)),
    locations = cells_body(columns = address)
  ) |>
  cols_align(align = "left") |>
  opt_align_table_header(align = "left")

This image of a table was generated from the third code example in the `fmt_email()` help file.

Function ID

3-22

Function Introduced

v0.11.0 (July 9, 2024)