From 0d4b0e362bb9d2d10f2a047f72d3c0056a41770f Mon Sep 17 00:00:00 2001
From: Craig Williams <craig@avsdev.uk>
Date: Thu, 5 Feb 2026 10:55:30 +0000
Subject: [PATCH] Added methods for manipulating element classes and improved
 the optional/required when fieldset is used

---
 NAMESPACE                 |  3 +++
 R/htmlClassManipulation.R | 49 +++++++++++++++++++++++++++++++++++++++
 R/htmlMarkOptional.R      |  4 +++-
 R/htmlMarkRequired.R      |  9 +++++--
 man/htmlAddClasses.Rd     | 23 ++++++++++++++++++
 man/htmlButtonStyle.Rd    | 23 ++++++++++++++++++
 man/htmlRemoveClasses.Rd  | 23 ++++++++++++++++++
 7 files changed, 131 insertions(+), 3 deletions(-)
 create mode 100644 R/htmlClassManipulation.R
 create mode 100644 man/htmlAddClasses.Rd
 create mode 100644 man/htmlButtonStyle.Rd
 create mode 100644 man/htmlRemoveClasses.Rd

diff --git a/NAMESPACE b/NAMESPACE
index d82ac60..b0918d1 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -3,12 +3,15 @@
 export(htmlAddBoxAttributes)
 export(htmlAddBoxHelpLink)
 export(htmlAddBoxRegionFromTitle)
+export(htmlAddClasses)
+export(htmlButtonStyle)
 export(htmlDisableAutocomplete)
 export(htmlFixBoxCollapseButtonAria)
 export(htmlMarkOptional)
 export(htmlMarkRequired)
 export(htmlRemoveAttributes)
 export(htmlRemoveBoxTitle)
+export(htmlRemoveClasses)
 export(htmlReplaceBoxTitleLevel)
 export(htmlSetMaxLength)
 export(htmlSetMinLength)
diff --git a/R/htmlClassManipulation.R b/R/htmlClassManipulation.R
new file mode 100644
index 0000000..04db5da
--- /dev/null
+++ b/R/htmlClassManipulation.R
@@ -0,0 +1,49 @@
+#' Add classes to an HTML element
+#'
+#' @param el The element to add the class(es) to
+#' @param classes The class(es) to be added
+#'
+#' @return The modified element
+#' @export
+#'
+#' @examples
+#' x <- shiny::tags$div()
+#' htmlAddClasses(x, "btn-warning")
+htmlAddClasses <- function(el, classes) {
+  htmltools::tagQuery(el)$addClass(classes)$allTags()
+}
+
+#' Remove classes from an HTML element
+#'
+#' @param el The element to remove the class(es) from
+#' @param classes The class(es) to be added
+#'
+#' @return The modified element
+#' @export
+#'
+#' @examples
+#' x <- shiny::tags$div(class = "btn btn-warning")
+#' htmlRemoveClasses(x, "btn-warning")
+htmlRemoveClasses <- function(el, classes) {
+  htmltools::tagQuery(el)$removeClass(classes)$allTags()
+}
+
+#' Changes the style of a button from btn-default to another style
+#'
+#' @param el The button
+#' @param style The style to change the button on
+#'
+#' @return The modified element
+#' @export
+#'
+#' @examples
+#' x <- shiny::tags$div(class = "btn btn-warning")
+#' htmlButtonStyle(x, "warning")
+htmlButtonStyle <- function(el, style) {
+  stopifnot(style %in% c(
+    "default", "primary", "info", "warning", "success", "danger", "link"
+  ))
+  el <- htmlRemoveClasses(el, "btn-default")
+  el <- htmlAddClasses(el, paste0("btn-", style))
+  el
+}
diff --git a/R/htmlMarkOptional.R b/R/htmlMarkOptional.R
index 1f789e2..95fadf4 100644
--- a/R/htmlMarkOptional.R
+++ b/R/htmlMarkOptional.R
@@ -12,7 +12,9 @@
 htmlMarkOptional <- function(input, optClass = "text-muted font-italic") {
   opt_span <- htmltools::tags$span(class = optClass, " (optional)")
   tq <- htmltools::tagQuery(input)
-  if (tq$hasClass("shiny-input-checkboxgroup")) {
+  if (tq$find("legend")$length() > 0) {
+    tq <- tq$children("legend")$append(opt_span)$reset()
+  } else if (tq$hasClass("shiny-input-checkboxgroup")) {
     tq <- tq$children("label")$append(opt_span)$reset()
   } else if (tq$find(".shiny-options-group")$length() > 0) {
     tq <- tq$children("label")$append(opt_span)$reset()
diff --git a/R/htmlMarkRequired.R b/R/htmlMarkRequired.R
index ab0041d..6539d20 100644
--- a/R/htmlMarkRequired.R
+++ b/R/htmlMarkRequired.R
@@ -12,12 +12,17 @@
 htmlMarkRequired <- function(input, reqClass = "text-danger required") {
   req_span <- htmltools::tags$span(class = reqClass, "*")
   tq <- htmltools::tagQuery(input)
-  if (tq$hasClass("shiny-input-checkboxgroup")) {
+  if (tq$find("legend")$length() > 0) {
+    tq <- tq$children("legend")$append(req_span)$reset()
+    tq <- tq$find("input")$addAttr(
+      required = "true", `aria-required` = "true"
+    )$reset()
+  } else if (tq$hasClass("shiny-input-checkboxgroup")) {
     tq <- tq$addAttr(`aria-required` = "true")$reset()
     tq <- tq$children("label")$append(req_span)$reset()
   } else if (tq$find(".shiny-options-group")$length() > 0) {
-    tq <- tq$children("label")$append(req_span)$reset()
     tq <- tq$addAttr(`aria-required` = "true")$reset()
+    tq <- tq$children("label")$append(req_span)$reset()
     tq <- tq$find("input")$addAttr(
       required = "true", `aria-required` = "true"
     )$reset()
diff --git a/man/htmlAddClasses.Rd b/man/htmlAddClasses.Rd
new file mode 100644
index 0000000..3f377fa
--- /dev/null
+++ b/man/htmlAddClasses.Rd
@@ -0,0 +1,23 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/htmlClassManipulation.R
+\name{htmlAddClasses}
+\alias{htmlAddClasses}
+\title{Add classes to an HTML element}
+\usage{
+htmlAddClasses(el, classes)
+}
+\arguments{
+\item{el}{The element to add the class(es) to}
+
+\item{classes}{The class(es) to be added}
+}
+\value{
+The modified element
+}
+\description{
+Add classes to an HTML element
+}
+\examples{
+x <- shiny::tags$div()
+htmlAddClasses(x, "btn-warning")
+}
diff --git a/man/htmlButtonStyle.Rd b/man/htmlButtonStyle.Rd
new file mode 100644
index 0000000..9eb55e9
--- /dev/null
+++ b/man/htmlButtonStyle.Rd
@@ -0,0 +1,23 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/htmlClassManipulation.R
+\name{htmlButtonStyle}
+\alias{htmlButtonStyle}
+\title{Changes the style of a button from btn-default to another style}
+\usage{
+htmlButtonStyle(el, style)
+}
+\arguments{
+\item{el}{The button}
+
+\item{style}{The style to change the button on}
+}
+\value{
+The modified element
+}
+\description{
+Changes the style of a button from btn-default to another style
+}
+\examples{
+x <- shiny::tags$div(class = "btn btn-warning")
+htmlButtonStyle(x, "warning")
+}
diff --git a/man/htmlRemoveClasses.Rd b/man/htmlRemoveClasses.Rd
new file mode 100644
index 0000000..8c38944
--- /dev/null
+++ b/man/htmlRemoveClasses.Rd
@@ -0,0 +1,23 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/htmlClassManipulation.R
+\name{htmlRemoveClasses}
+\alias{htmlRemoveClasses}
+\title{Remove classes from an HTML element}
+\usage{
+htmlRemoveClasses(el, classes)
+}
+\arguments{
+\item{el}{The element to remove the class(es) from}
+
+\item{classes}{The class(es) to be added}
+}
+\value{
+The modified element
+}
+\description{
+Remove classes from an HTML element
+}
+\examples{
+x <- shiny::tags$div(class = "btn btn-warning")
+htmlRemoveClasses(x, "btn-warning")
+}