ChoicesFilterState: 'FilterState' object for categorical data

In teal.slice: Filter Module for 'teal' Applications

FilterState object for categorical data

Description

Manages choosing elements from a set.

Super class

teal.slice::FilterState -> ChoicesFilterState

Methods

Public methods

• ChoicesFilterState$new()

• ChoicesFilterState$get_call()

• ChoicesFilterState$clone()

Inherited methods

• teal.slice::FilterState$finalize()
• teal.slice::FilterState$format()
• teal.slice::FilterState$get_state()
• teal.slice::FilterState$print()
• teal.slice::FilterState$server()
• teal.slice::FilterState$set_state()
• teal.slice::FilterState$ui()

---

Method new()

Initialize a FilterState object.

Usage

ChoicesFilterState$new(
  x,
  x_reactive = reactive(NULL),
  slice,
  extract_type = character(0)
)

Arguments

x

(character) variable to be filtered.

x_reactive

(reactive) returning vector of the same type as x. Is used to update counts following the change in values of the filtered dataset. If it is set to reactive(NULL) then counts based on filtered dataset are not shown.

slice

(teal_slice) specification of this filter state. teal_slice is stored in the object and set_state directly manipulates values within teal_slice. get_state returns teal_slice object which can be reused in other places. Note that teal_slice is a reactiveValues, which means it has reference semantics, i.e. changes made to an object are automatically reflected in all places that refer to the same teal_slice.

extract_type

(character) specifying whether condition calls should be prefixed by dataname. Possible values:

• character(0) (default) varname in the condition call will not be prefixed

• "list" varname in the condition call will be returned as ⁠<dataname>$<varname>⁠

• "matrix" varname in the condition call will be returned as ⁠<dataname>[, <varname>]⁠

Returns

Object of class ChoicesFilterState, invisibly.

---

Method get_call()

Returns reproducible condition call for current selection. For this class returned call looks like ⁠<varname> %in% c(<values selected>)⁠ with optional ⁠is.na(<varname>)⁠.

Usage

ChoicesFilterState$get_call(dataname)

Arguments

dataname

(character(1)) name of data set; defaults to private$get_dataname()

Returns

call or NULL

---

Method clone()

The objects of this class are cloneable with this method.

Usage

ChoicesFilterState$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

Examples

# use non-exported function from teal.slice
include_css_files <- getFromNamespace("include_css_files", "teal.slice")
include_js_files <- getFromNamespace("include_js_files", "teal.slice")
ChoicesFilterState <- getFromNamespace("ChoicesFilterState", "teal.slice")

library(shiny)

filter_state <- ChoicesFilterState$new(
  x = c(LETTERS, NA),
  slice = teal_slice(varname = "var", dataname = "data")
)
isolate(filter_state$get_call())
filter_state$set_state(
  teal_slice(
    dataname = "data",
    varname = "var",
    selected = "A",
    keep_na = TRUE
  )
)
isolate(filter_state$get_call())

# working filter in an app
library(shinyjs)

data_choices <- c(sample(letters[1:4], 100, replace = TRUE), NA)
attr(data_choices, "label") <- "lowercase letters"
fs <- ChoicesFilterState$new(
  x = data_choices,
  slice = teal_slice(
    dataname = "data", varname = "variable", selected = c("a", "c"), keep_na = TRUE
  )
)

ui <- fluidPage(
  useShinyjs(),
  include_css_files(pattern = "filter-panel"),
  include_js_files(pattern = "count-bar-labels"),
  column(4, tags$div(
    tags$h4("ChoicesFilterState"),
    fs$ui("fs")
  )),
  column(4, tags$div(
    tags$h4("Condition (i.e. call)"), # display the condition call generated by this FilterState
    textOutput("condition_choices"), tags$br(),
    tags$h4("Unformatted state"), # display raw filter state
    textOutput("unformatted_choices"), tags$br(),
    tags$h4("Formatted state"), # display human readable filter state
    textOutput("formatted_choices"), tags$br()
  )),
  column(4, tags$div(
    tags$h4("Programmatic filter control"),
    actionButton("button1_choices", "set drop NA", width = "100%"), tags$br(),
    actionButton("button2_choices", "set keep NA", width = "100%"), tags$br(),
    actionButton("button3_choices", "set selection: a, b", width = "100%"), tags$br(),
    actionButton("button4_choices", "deselect all", width = "100%"), tags$br(),
    actionButton("button0_choices", "set initial state", width = "100%"), tags$br()
  ))
)

server <- function(input, output, session) {
  fs$server("fs")
  output$condition_choices <- renderPrint(fs$get_call())
  output$formatted_choices <- renderText(fs$format())
  output$unformatted_choices <- renderPrint(fs$get_state())
  # modify filter state programmatically
  observeEvent(
    input$button1_choices,
    fs$set_state(
      teal_slice(dataname = "data", varname = "variable", keep_na = FALSE)
    )
  )
  observeEvent(
    input$button2_choices,
    fs$set_state(
      teal_slice(dataname = "data", varname = "variable", keep_na = TRUE)
    )
  )
  observeEvent(
    input$button3_choices,
    fs$set_state(
      teal_slice(dataname = "data", varname = "variable", selected = c("a", "b"))
    )
  )
  observeEvent(
    input$button4_choices,
    fs$set_state(
      teal_slice(dataname = "data", varname = "variable", selected = character(0), keep_na = TRUE)
    )
  )
  observeEvent(
    input$button0_choices,
    fs$set_state(
      teal_slice(dataname = "data", varname = "variable", selected = c("a", "c"), keep_na = TRUE)
    )
  )
}

if (interactive()) {
  shinyApp(ui, server)
}

teal.slice documentation built on April 4, 2025, 12:39 a.m.