simplify the verbatim pop up (#127)

closes #102

I simplify the code by placing the observe one module deeper.

Signed-off-by: Maciej Nasinski <nasinski.maciej@gmail.com>

R/verbatim_popup.R

@@ -37,17 +37,14 @@ verbatim_popup_ui <- function(id, button_label, type = c("button", "link"), ...)
   ns <- shiny::NS(id)
   ui_args <- list(
     inputId = ns("button"),
-    label = div(
-      button_label,
-      shiny::uiOutput(ns("disable_controller"), inline = TRUE) # this is dummy output - see the comment in srv
-    )
+    label = button_label
   )
 
-
   shiny::tagList(
     shiny::singleton(
       shiny::tags$head(shiny::includeScript(system.file("js/verbatim_popup.js", package = "teal.widgets")))
     ),
+    shinyjs::useShinyjs(),
     do.call(ui_function, c(ui_args, list(...)))
   )
 }
@@ -61,7 +58,7 @@ verbatim_popup_ui <- function(id, button_label, type = c("button", "link"), ...)
 #' @param style (`logical(1)`) whether to style the `verbatim_content` using `styler::style_text`.
 #' If `verbatim_content` is a `condition` or `reactive` holding `condition` then this argument is ignored
 #' @param disabled (`reactive(1)`) the `shiny` reactive value holding a `logical`. The popup button is disabled
-#' when the flag is `TRUE` and enabled otherwise
+#' when the flag is `TRUE` and enabled otherwise.
 #'
 verbatim_popup_srv <- function(id, verbatim_content, title, style = FALSE, disabled = shiny::reactiveVal(FALSE)) {
   checkmate::assert_string(id)
@@ -70,39 +67,18 @@ verbatim_popup_srv <- function(id, verbatim_content, title, style = FALSE, disab
   checkmate::assert_class(disabled, classes = "reactive")
   moduleServer(id, function(input, output, session) {
     ns <- session$ns
-    # In normal case we could enable/disable using observeEvent(disabled_flag(), ...)
-    #  but observeEvent doesn't care whether output is displayed or not
-    #  This means that if we want to prevent calulation of disabled_flag for hidden
-    #  output, we need to use renderUI which triggers when the output is shown.
-    output$disable_controller <- shiny::renderUI(disable_button(disabled, "button"))
     modal_content <- format_content(verbatim_content, style)
     button_click_observer(
       click_event = shiny::reactive(input$button),
       copy_button_id = ns("copy_button"),
       copied_area_id = ns("verbatim_content"),
       modal_title = title,
-      modal_content = modal_content
+      modal_content = modal_content,
+      disabled = disabled
     )
   })
 }
 
-#' Disables a button
-#'
-#' @details
-#' When the flag is `TRUE` the button to open the popup is disabled; it is enabled otherwise.
-#'
-#' @keywords internal
-#' @param disabled_flag (`reactive`) containing the flag
-#' @param button_id (`character(1)`) the id of the controlled button
-disable_button <- function(disabled_flag, button_id) {
-  if (disabled_flag()) {
-    shinyjs::disable(button_id)
-  } else {
-    shinyjs::enable(button_id)
-  }
-  NULL
-}
-
 #' Creates a `shiny` observer handling button clicks.
 #'
 #' @description
@@ -115,7 +91,25 @@ disable_button <- function(disabled_flag, button_id) {
 #' @param copied_area_id (`character(1)`) the id of the element which contents are copied
 #' @param modal_title (`character(1)`) the title of the modal window
 #' @param modal_content (`reactive`) the content of the modal window
-button_click_observer <- function(click_event, copy_button_id, copied_area_id, modal_title, modal_content) {
+#' @param disabled (`reactive(1)`) the `shiny` reactive value holding a `logical`. The popup button is disabled
+#' when the flag is `TRUE` and enabled otherwise.
+button_click_observer <- function(click_event,
+                                  copy_button_id,
+                                  copied_area_id,
+                                  modal_title,
+                                  modal_content,
+                                  disabled) {
+  shiny::observeEvent(
+    disabled(),
+    handlerExpr = {
+      if (disabled()) {
+        shinyjs::disable("button")
+      } else {
+        shinyjs::enable("button")
+      }
+    }
+  )
+
   shiny::observeEvent(
     click_event(),
     handlerExpr = {

tests/testthat/test-verbatim_popup.R

@@ -77,15 +77,6 @@ testthat::test_that(
   }
 )
 
-testthat::test_that("disable_button returns NULL", {
-  shiny::withReactiveDomain(
-    domain = shiny::MockShinySession$new(),
-    expr = testthat::expect_null(
-      isolate(disable_button(shiny::reactive(FALSE), "test_id"))
-    )
-  )
-})
-
 testthat::test_that("button_click_observer returns an observer", {
   testthat::expect_true(inherits(button_click_observer(
     click_event = shiny::reactive(0),