Index: openacs-4/packages/xowiki/tcl/form-field-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/form-field-procs.tcl,v
diff -u -N -r1.284.2.224 -r1.284.2.225
--- openacs-4/packages/xowiki/tcl/form-field-procs.tcl	6 Oct 2022 17:27:48 -0000	1.284.2.224
+++ openacs-4/packages/xowiki/tcl/form-field-procs.tcl	18 Oct 2022 12:58:57 -0000	1.284.2.225
@@ -5060,6 +5060,7 @@
     {as_box:boolean false}
     {keep_order:boolean false}
     {dnd:boolean true}
+    {bulk_operation:boolean false}
   }  -ad_doc {
     Class for selecting a subset from a list of candidates.
     @param as_box makes something like in info box in wikipedia (right floated)
@@ -5080,6 +5081,18 @@
         -script "selection_area_${event}_handler(event);"
   }
 
+  candidate_box_select instproc add_bulk_handler {
+    -id:required
+    -event:required
+    -operation:required
+  } {
+    template::add_event_listener \
+        -id $id \
+        -event $event \
+        -preventdefault=false \
+        -script "selection_area_bulk_operation_handler(event,'$operation');"
+  }
+
   candidate_box_select instproc render_input {} {
     #:msg "mul ${:multiple} dnd ${:dnd}"
     # makes only sense currently for multiple selects
@@ -5129,6 +5142,12 @@
           ::html::div -class workarea {
             ::html::h3 { ::html::t "#xowiki.Selection#"}
             # TODO what todo with DISABLED?
+            if {${:bulk_operation}} {
+              ::html::div -id ${:id}.bulk_remove -role "button" -class "text-center bulk-remove" {
+                ::html::t ">>"
+                :add_bulk_handler -id ${:id}.bulk_remove -event click -operation bulk_remove
+              }
+            }
             ::html::ul -class "region selected" \
                 -id ${:id}.selected {
                   foreach v $selected {
@@ -5148,6 +5167,12 @@
           #
           ::html::div -class workarea {
             ::html::h3 { ::html::t "#xowiki.Candidates#"}
+            if {${:bulk_operation}} {
+              ::html::div -id ${:id}.bulk_add -role "button" -class "text-center bulk-add" {
+                ::html::t "<<"
+                :add_bulk_handler -id ${:id}.bulk_add -event click -operation bulk_add
+              }
+            }
             ::html::ul -id ${:id}.candidates -class region {
               foreach v $candidates {
                 set id ${:id}.[dict get $labels $v serial]
Index: openacs-4/packages/xowiki/www/resources/selection-area.js
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/www/resources/Attic/selection-area.js,v
diff -u -N -r1.1.2.4 -r1.1.2.5
--- openacs-4/packages/xowiki/www/resources/selection-area.js	13 Aug 2019 07:27:02 -0000	1.1.2.4
+++ openacs-4/packages/xowiki/www/resources/selection-area.js	18 Oct 2022 12:58:57 -0000	1.1.2.5
@@ -47,9 +47,13 @@
     // Reparent the dropped item
     ul.appendChild(sourceElement);
 
+    var id = ul.parentElement.parentElement.id;
+    selection_area_update_internal_representation(id);
+}
+
+function selection_area_update_internal_representation (id) {
     // Update the internal representation based on the data-element of
     // the list items.
-    var id       = ul.parentElement.parentElement.id;
     var textarea = document.getElementById(id + ".text");
     var items    = document.getElementById(id + ".selected").getElementsByTagName('LI');
     var internalRep = "";
@@ -61,6 +65,28 @@
     textarea.value = internalRep;
 }
 
+function selection_area_bulk_operation_handler(ev, operation) {
+    if (operation == 'bulk_add') {
+        var source_class = '.candidates';
+        var destination_class = '.selected';
+    } else {
+        // bulk_remove operation
+        var source_class = '.selected';
+        var destination_class = '.candidates';
+    }
+
+    var id          = ev.target.previousSibling.parentElement.parentElement.id;
+    var source      = document.getElementById(id + source_class).getElementsByTagName('LI');
+    var destination = document.getElementById(id + destination_class);
+
+    // Reparent all source items
+    while(source.length > 0) {
+        destination.appendChild(source[0]);
+    }
+
+    selection_area_update_internal_representation(id);
+}
+
 /*
  * Local variables:
  *    mode: JavaScript