EmptyFilterState: 'FilterState' object for empty variables

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

FilterState object for empty variables

Description

FilterState subclass representing an empty variable.

Super class

teal.slice::FilterState -> EmptyFilterState

Methods

Public methods

• EmptyFilterState$new()

• EmptyFilterState$get_call()

• EmptyFilterState$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 EmptyFilterState object.

Usage

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

Arguments

x

(vector) 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.

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>]⁠

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.

Returns

Object of class EmptyFilterState, invisibly.

---

Method get_call()

Returns reproducible condition call for current selection relevant for selected variable type. Uses internal reactive values, hence must be called in reactive or isolated context.

Usage

EmptyFilterState$get_call(dataname)

Arguments

dataname

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

Returns

logical(1)

---

Method clone()

The objects of this class are cloneable with this method.

Usage

EmptyFilterState$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

Examples

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

library(shiny)

filter_state <- EmptyFilterState$new(
  x = NA,
  slice = teal_slice(varname = "x", dataname = "data"),
  extract_type = character(0)
)
isolate(filter_state$get_call())
filter_state$set_state(teal_slice(dataname = "data", varname = "x", keep_na = TRUE))
isolate(filter_state$get_call())

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