R/regexSelectUI.R

In regexSelect: Regular Expressions in 'shiny' Select Lists

#' @title Create UI object for a selectize list input control with regular expression capabilities
#' @description Create UI object for a selectize list that can be used to choose a single or
#'  multiple items from a list of values with extension for regular expression.
#' @param id id of shiny module used in regexSelect
#' @param label character, label of the selectize object
#' @param choices List of values to select from. If elements of the list are named, 
#' then that name rather than the value is displayed to the user. This can also be a 
#' named list whose elements are (either named or unnamed) lists or vectors. If this 
#' is the case, the outermost names will be used as the "optgroup" label for the elements 
#' in the respective sublist. This allows you to group and label similar choices.
#' @param checkbox.selected character, options of the checkbox to set as TRUE, see details, 
#' Default: c("enable", "ignore.case")
#' @param checkbox.inline boolean, render the checkbox choices inline (i.e. horizontally), 
#' Default: TRUE
#' @param checkbox.show boolean, show the checkbox options as part of UI output or hide them, 
#' Default: FALSE
#' @details checkbox.selected is used as a proxy for ellipses to pass arguments
#'  to a grep(selectize value, selectize choices,value=TRUE,...). This makes the 
#'  options in checkbox.selected the same as the arguments that pass to grep: ignore.case, 
#'  perl,fixed and invert. 
#'  
#'  In addition there are two more arguments that the user can set 
#'  enable which toggles the grep functionality to return it to regular selectize with options 
#'  multiple=TRUE and create=TRUE. The other argument is retain, this lets the user control if 
#'  the search terms are added to the selectize choices or to keep it as originally entered, 
#'  there by converting the selectize into a search field. If checkbox.show is false the 
#'  initial values passed through checkbox.selected will be used. 
#' @return A list of HTML elements that can be added to a UI definition.
#' @examples
#' if(interactive()){
#'ui <- shiny::fluidPage(
#'regexSelectUI(id = "a", label = "Variable:",choices = names(iris)),
#'shiny::tableOutput("data")
#')
#' 
#' 
#'ui.show <- shiny::fluidPage(
#'regexSelectUI(id = "a", label = "Variable:",choices = names(iris),checkbox.show = TRUE),
#'shiny::tableOutput("data")
#')
#'
#'server <- function(input, output, session) {
#'  curr_cols<-shiny::callModule(regexSelect, "a",shiny::reactive(names(iris)))
#'  
#'  shiny::observeEvent(curr_cols(),{
#'  cols_now<-curr_cols()
#'  if(length(cols_now)==0)  cols_now<-names(data())
#'  output$data <- shiny::renderTable({iris[,cols_now , drop = FALSE]}, rownames = TRUE)
#'  })
#'}
#'
#'#do not show regex checkboxes
#'shiny::shinyApp(ui, server)
#'
#'#show regex checkboxes
#'shiny::shinyApp(ui.show, server)
#'  }
#' @rdname regexSelectUI
#' @export 
#' @import shiny
#' @importFrom shinyjs useShinyjs
regexSelectUI <- function(id, label, choices,checkbox.selected=c('enable','ignore.case'),checkbox.inline=TRUE,checkbox.show=FALSE) {
  
  ns <- shiny::NS(id)
  
  checkbox_group<-function(checkbox.selected,checkbox.inline){
    shiny::checkboxGroupInput(inputId = ns('grep'),label = 'regex options',
                              choices = c('Enable'='enable',
                                          'Retain Searches'='retain',
                                          'Ignore Case'='ignore.case',
                                          'Perl'='perl',
                                          'Fixed'='fixed',
                                          'Invert'='invert'),
                              selected = checkbox.selected,
                              inline  = checkbox.inline)}
  
  tagOut<-shiny::tagList(
    shinyjs::useShinyjs(),
    shiny::selectizeInput(inputId = ns("variable"),
                          label = label,
                          choices = choices,
                          options=list(multiple=TRUE,create = TRUE)),
    checkbox_group(checkbox.selected,checkbox.inline))
  
  if(!checkbox.show) tagOut[[3]]=shinyjs::hidden(checkbox_group(checkbox.selected,checkbox.inline))
  
  tagOut
}