tableHTML

Removing Row Names

To remove row names from the HTML table you can type:

tableHTML(mtcars, rownames=FALSE)

Adding a table class

The class argument sets the class name for the table. The default will be of the form table_xxx (random 4-digit number). This makes it easier to add css to it in case there are multiple tables.

mytable <- tableHTML(mtcars)
str(mytable)
# Classes 'tableHTML', 'html', 'character'  atomic [1:1] 
# <table class=table_1901 border=1 style="border-collapse: collapse;">
# <tr>
#   <th id="tableHTML_header_1"> </th>
#   <th id="tableHTML_header_2">mpg</th>
#   <th id="tableHTML_header_3">cyl</th>
# truncated...

And with a custom class:

mytable <- tableHTML(mtcars, class='myClass')
str(mytable)
# Classes 'tableHTML', 'html', 'character'  atomic [1:1] 
# <table class=myClass border=1 style="border-collapse: collapse;">
# <tr>
#   <th id="tableHTML_header_1"> </th>
#   <th id="tableHTML_header_2">mpg</th>
#   <th id="tableHTML_header_3">cyl</th>
# truncated...

Adding Second Headers that span multiple columns

In case you would like to add second headers that span multiple columns you can do it by providing a list in the second_header argument. The first element will contain the column spans (i.e. a numeric atomic vector) whereas the second element will contain the names (i.e. a character atomic vector).

For example:

tableHTML(mtcars, second_headers = list(c(3, 4, 5), c('col1', 'col2', 'col3')))

Adding Row Groups that span multiple rows

In case you would like to add row groups that span multiple rows you can do it by providing a list in the row_groups argument. The first element will contain the row spans (i.e. a numeric atomic vector) whereas the second element will contain the names (i.e. a character atomic vector).

For example:

tableHTML(mtcars, 
          rownames = FALSE, 
          row_groups = list(c(10, 10, 12), c('Group 1', 'Group 2', 'Group 3')))

Change the widths

Obviously, the above tables are far from appealing since they have no css. So we can start styling them now. A very important feature is to be able to control the column widths. You can do this with the widths argument.

The widths argument specifies the columns’ width in pixels. It needs to have the same length as the number of columns (if rownames is TRUE, rownames are also considered a column). If second headers exist these will stretch according to their underlying columns’ widths.

As an example:

tableHTML(mtcars, 
          widths = rep(100, 12), 
          second_headers = list(c(3, 4, 5), c('col1', 'col2', 'col3')))

Change the border

By default the table border is set to 1. If you set to 0 it will remove all the lines (the grid) completely. Setting it to an integer greater than 1 will increase the size of the table’s outside border.

tableHTML(mtcars, border = 0)

Adding a caption

If you want a caption (title) for your table you can add one with the caption argument.

tableHTML(mtcars, caption = 'This is  a table')

Adding a footer

If you want a footer for your table you can add one with the footer argument.

tableHTML(mtcars, footer = 'This is  a footer')

Collapse the table

By default tableHTML collapses the table, so that there is no spacing between cells. You can change this behaviour by using the collapse argument.

tableHTML(mtcars, collapse = 'separate')

In order to use a non-collapsed table on shiny you need to use the collapse = 'separate_shiny' argument. shiny uses bootstrap 3 by default which uses table {border-collapse: collapse; border-spacing:0;} in its css. collapse = 'separate_shiny' will use the !important keyword in HTML which overwrites the default bootstrap 3 styling. Web developers argue that using !important can be dangerous since it overwrites previously set styles, so only use it on shiny or other web applications where tables are collapsed by default.

tableHTML(mtcars, collapse = 'separate_shiny')

Spacing

If collapse is either separate or separate_shiny then you can use the spacing argument to change the spacing between the cells. This only works if collapse is separate or separate_shiny otherwise it is not taken into account. You can use one or two length distances. If two length distances are used, the first specifies the horizontal spacing and the second one the vertical spacing.

tableHTML(mtcars, collapse = 'separate_shiny', spacing = '2px')

tableHTML(mtcars, collapse = 'separate_shiny', spacing = '5px 2px')

Escaping

By default tableHTML will escape < and > because they open or close the table’s tags if they are part of the text of the data.frame, which results into missing text. For example you can see the difference below:

df <- data.frame(a = c('abcd<efgh'))
tableHTML(df, escape = FALSE, rownames = FALSE)

tableHTML(df, escape = TRUE, rownames = FALSE)

In order to fix this, the argument escape is set to TRUE by default. < and > will be replaced with &#62 and &#60. However, if you would like to include clickable links in your HTML table you should not escape by setting escape = FALSE.

add_css_* family

These functions add inline CSS to the HTML table. The package has been developed so that the functions are chained with the %>% (pipe) operator which comes from the magrittr package. You can chain as many of those as you want when building your HTML table. The CSS code is added within the HTML table. This is ok for simple table styling but for more complex CSS styles (like the hover selector) it would still require a separate css file (we will see how to work with those in shiny later on).

mtcars %>%
  tableHTML(widths = c(140, rep(45, 11))) %>% 
  add_css_row(css = list(c('background-color', 'border'), c('lightblue', '2px solid lightgray')))

mtcars %>%
  tableHTML(widths = c(140, rep(45, 11))) %>% 
  add_css_row(css = list(c('background-color', 'border'), c('lightblue', '2px solid lightgray')),
              rows = 2:33)

mtcars %>%
  tableHTML(widths = c(140, rep(45, 11))) %>% 
  add_css_row(css = list('background-color', '#f2f2f2'),
              rows = odd(1:33)) %>%
  add_css_row(css = list('background-color', '#e6f0ff'),
              rows = even(1:33))

mtcars %>%
  tableHTML(widths = c(140, rep(45, 11))) %>% 
  add_css_column(css = list(c('background-color', 'border'), c('lightblue', '3px solid lightgray')), 
                 columns = c('cyl', 'hp', 'rownames'))

mtcars %>%
  tableHTML(widths = c(140, rep(45, 11))) %>% 
  add_css_row(css = list('background-color', '#f2f2f2')) %>%
  add_css_column(css = list('background-color', 'lightblue'), 
                 columns = c('cyl', 'hp', 'rownames')) 

mytable <- tableHTML(mtcars)
print(mytable, viewer = FALSE)
<table style="border-collapse:collapse;" class=table_2079 border=1>
<thead>
<tr>
  <th id="tableHTML_header_1"> </th>
  <th id="tableHTML_header_2">mpg</th>
  <th id="tableHTML_header_3">cyl</th>
truncated...

 tableHTML(mtcars) %>%
   add_css_rows_in_column(css = list('background-color', 
                                    rep(c('red', 'green'), each = 16)),
                         column = 'mpg')