including empty value in Filter box dropdown for factor columns

[AhmedKhaled945]

Hello, so i have an app that has multiple factor columns, and for those columns i need to have the ability to filter for any value, even the empty ones, is there an extension or a workaround to make this happen?

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[wholmes105]

What do you mean by empty values? NA and empty strings, when converted to factors and put in a datatable, are not included in the column filters presently. However, " " is kept as-is and included in the column filter, with the caveat that the row height is much shorter than it would be if it had an alphanumeric character in it (6px tall vs 26px) by default. As long as whatever value you define as empty can be replaced with " ", you can fix this with a bit of CSS:

shinyApp(
  ui = fluidPage(
    tags$style(HTML(
".option {
  height: 26px;
}"
    )),
    
    datatable(
      data = data.frame(
        dummy_col = as.factor(c('dummy_value', ' '))
      ),
      filter = 'top'
    )
  ),
  server = function(input, output, session) {}
)