formattable Another nice table-making package is formattable. The cute heatmap-style colour formatting and the easy-to-use formatter functions make formattable very appealing. color_tile() fills the cells with a colour gradient corresponding to the values color_bar() adds a colour bar to each cell, where the length is proportional to the value The true_false_formatter() defined below demonstrates how to define your own formatting function, in this case formatting TRUE, FALSE and NA as green, red and black.

If you want the features of both DT and formattable, you can combine them by converting the formattable() output to as.datatable(), and much of the formattable features will be preserved.

However, one problem I had was that when using DT::datatable, missing values (NA) are left blank in the display (which I prefer), but in the converted from formattable() version, NA’s are printed. Also, color_bar columns seem to be converted to character, which can no longer be sorted numerically.

reactable Next I tried reactable, a package based on the React Table library.

Columns are customised via the columns argument, which takes a named list of column definitions defined using colDef(). These include format definitions created using colFormat.

In the end, I used DT::datatable() in my Shiny app, because I found it the easiest, fastest, and most comprehensive. I’ve been able to achieve most of the features I wanted using just DT.

Heatmap-like fill effect:

apply the formatStyle() function to the output of datatable() to set the backgroundColor for selected columns:

Abbreviate long cells

Sometimes some cells have a large amount of text that would mess up the table layout if I showed it all. In these cases, I like to abbreviate long values and show the full text in a tooltip. To do this, you can use JavaScript to format the column to show a substring with “…” and the full string in a tooltip (<span title="Long string">Substring...</span) when values are longer than N characters (in this case 10 characters). You can do this using columnDefs and pass JavaScript with the JS() function:

Really plain table Sometimes I don’t need any of the faff. Here’s how to get rid of it all:

headerCallbackRemoveHeaderFooter <- c( "function(thead, data, start, end, display){", " $('th', thead).css('display', 'none');", "}" )

datatable( my_pic_villagers, options = list( dom = "t", ordering = FALSE, paging = FALSE, searching = FALSE, headerCallback = JS(headerCallbackRemoveHeaderFooter) ), selection = 'none', callback = JS( "$('table.dataTable.no-footer').css('border-bottom', 'none');" ), class = 'row-border', escape = FALSE, rownames = FALSE, filter = "none", width = 500 )

Shiny was designed with an emphasis on distinct input and output components in the UI. Inputs send values from the client to the server, and when the server has values for the client to display, they are received and rendered by outputs.

You want the server to trigger logic on the client that doesn’t naturally relate to any single output.

You want the server to update a specific (custom) output on the client, but not by totally invalidating the output and replacing the value, just making a targeted modification.

You have some client JavaScript that isn’t related to any particular input, yet wants to trigger some behavior in R. For example, binding keyboard shortcuts on the web page to R functions on the server, or alerting R when the size of the browser window has changed.