ErrorController: ErrorController

In DavidBarke/QWUtils: Useful Methods For Programming with Shiny

Description

Reactive R6Class that returns HTML according to a test function. Modules like checked_text_input or observed_vector_input provide an argument accepting an ErrorController or ErrorControllerList that expands the module's default tests.

Usage

error_controller <- shiny::isolate({ErrorController$new(
  fun = function(x) purrr::is_null(x),
  ui_true = "x is NULL",
  ui_false = "x is not NULL",
  error = TRUE
)})

Methods

new(fun, ui_true = NULL, ui_false = NULL, priority = 0, error = NULL)

Initialize the error controller.

fun	Function with exactly one argument returning TRUE or FALSE.
ui_true	HTML-like tag to be returned by this$get_ui(), if this$fun(this$value) == TRUE.
ui_false	HTML-like tag to be returned by this$get_ui(), if this$fun(this$value) == FALSE.
priority	Numeric which is used by ErrorControllerList to determine the order in which to display the UIs of their error controllers.
error	Determine which result of this$fun(this$value) shall be counted as an error or use NULL if either result produces no error, which is useful for displaying warnings or help messages based on user input.

get_priority()

Get the error controller's priority.

get_ui()

Get the error controller's ui.

has_error()

Get a logical indicating whether this$fun(this$value) equals this$error. If error = NULL in this$new(), this method always returns false.

set_priority(priority)

Set the priority of the error controller.

set_value

Set the value which is checked by this$fun().

DavidBarke/QWUtils documentation built on Jan. 13, 2020, 11:52 a.m.