States & Categories that are in use cannot be moved to trash

administrator/language/en-GB/en-GB.com_workflow.ini

@@ -3,12 +3,12 @@
 ; License GNU General Public License version 2 or later; see LICENSE.txt, see LICENSE.php
 ; Note : All ini files need to be saved as UTF-8
 
-COM_CONTACT_FIELD_CATEGORY_LIST_DESC="Please choose a Category from the list."
+COM_CONTACT_FIELD_CATEGORY_LIST_DESC="Please choose a category from the list."
 COM_WORKFLOW_ARE_YOU_SURE="Are you sure?"
 COM_WORKFLOW_ASC_CONDITION="Condition ascending"
 COM_WORKFLOW_AUTHOR="Author"
 COM_WORKFLOW_BASIC_TAB="Basic"
-COM_WORKFLOW_CONDITION="Condition of items in this State: "
+COM_WORKFLOW_CONDITION="Condition of items in this state: "
 COM_WORKFLOW_CONDITION_DESC="Defines item behaviour."
 COM_WORKFLOW_CONFIGURATION="Workflow: Options"
 COM_WORKFLOW_COUNT_STATES="States"
@@ -27,16 +27,16 @@ COM_WORKFLOW_DESC_TAB="Description"
 COM_WORKFLOW_DISABLE_DEFAULT="Cannot change default state of this item."
 COM_WORKFLOW_EDIT="Edit"
 COM_WORKFLOW_EDIT_TAB="Edit"
-COM_WORKFLOW_ERROR_UPDATE_STATE="Error while updating the State."
+COM_WORKFLOW_ERROR_UPDATE_STATE="Error while updating the state."
 COM_WORKFLOW_FIELD_CATEGORY_LIST_LABEL="Category List"
 COM_WORKFLOW_FIELD_IS_DEFAULT_DESC="If set to default, this will be saved for the component."
 COM_WORKFLOW_FIELD_IS_DEFAULT_LABEL="Default"
 COM_WORKFLOW_FIELD_TITLE_DESC="Title"
 COM_WORKFLOW_FIELD_TITLE_LABEL="Title"
 COM_WORKFLOW_FILTER_SEARCH_DESC="Filter the list of items."
 COM_WORKFLOW_FILTER_SEARCH_LABEL="Search"
-COM_WORKFLOW_FROM_STATE="From State"
-COM_WORKFLOW_FROM_STATE_DESC="Select current State."
+COM_WORKFLOW_FROM_STATE="From state"
+COM_WORKFLOW_FROM_STATE_DESC="Select current state."
 COM_WORKFLOW_ID="ID"
 COM_WORKFLOW_ITEM_MUST_PUBLISHED="Item must be published to set default state."
 COM_WORKFLOW_ITEM_SET_DEFAULT="Item set to default."
@@ -84,14 +84,14 @@ COM_WORKFLOW_TITLE="Title"
 COM_WORKFLOW_TOOLBAR_SET_HOME="Default"
 COM_WORKFLOW_TO_MANY_ITEMS="Too many items selected."
 COM_WORKFLOW_TO_STATE="To State"
-COM_WORKFLOW_TO_STATE_DESC="Select target State."
+COM_WORKFLOW_TO_STATE_DESC="Select target state."
 COM_WORKFLOW_TRANSITION="Transition"
 COM_WORKFLOW_TRANSITIONS="Transitions"
 COM_WORKFLOW_TRANSITIONS_LIST="%s Transitions List"
 COM_WORKFLOW_TRANSITION_ADD="Add Transition"
 COM_WORKFLOW_TRANSITION_DUPLICATE="This transition already exists."
 COM_WORKFLOW_TRANSITION_EDIT="Edit Transition"
-COM_WORKFLOW_TRANSITION_THE_SAME_STATE="Current State and target State are the same."
+COM_WORKFLOW_TRANSITION_THE_SAME_STATE="Current state and target state are the same."
 COM_WORKFLOW_TRASHED="Trashed"
 COM_WORKFLOW_UNPUBLISHED="Unpublished"
 COM_WORKFLOW_USER_GROUPS="User Group"

libraries/src/MVC/Model/AdminModel.php

@@ -62,6 +62,7 @@ abstract class AdminModel extends FormModel
 	 * @var    string
 	 * @since  1.6
 	 */
+
 	protected $event_before_save = null;
 
 	/**
@@ -191,7 +192,7 @@ public function __construct($config = array(), MVCFactoryInterface $factory = nu
 			$this->event_before_delete = 'onContentBeforeDelete';
 		}
 
-		if (isset($config['event_before_save']))
+        if (isset($config['event_before_save']))
 		{
 			$this->event_before_save = $config['event_before_save'];
 		}
@@ -957,6 +958,7 @@ protected function populateState()
 		// Load the parameters.
 		$value = \JComponentHelper::getParams($this->option);
 		$this->setState('params', $value);
+
 	}
 
 	/**
@@ -995,34 +997,56 @@ public function publish(&$pks, $value = 1)
 		// Access checks.
 		foreach ($pks as $i => $pk)
 		{
-			$table->reset();
+            $table->reset();
 
-			if ($table->load($pk))
-			{
-				if (!$this->canEditState($table))
-				{
-					// Prune items that you can't change.
-					unset($pks[$i]);
+            if ($table->load($pk))
+            {
 
-					\JLog::add(\JText::_('JLIB_APPLICATION_ERROR_EDITSTATE_NOT_PERMITTED'), \JLog::WARNING, 'jerror');
+                if (!$this->canEditState($table))
+                {
+                    // Prune items that you can't change.
+                    unset($pks[$i]);
 
-					return false;
-				}
+                    \JLog::add(\JText::_('JLIB_APPLICATION_ERROR_EDITSTATE_NOT_PERMITTED'), \JLog::WARNING, 'jerror');
 
-				// If the table is checked out by another user, drop it and report to the user trying to change its state.
-				if (property_exists($table, 'checked_out') && $table->checked_out && ($table->checked_out != $user->id))
-				{
-					\JLog::add(\JText::_('JLIB_APPLICATION_ERROR_CHECKIN_USER_MISMATCH'), \JLog::WARNING, 'jerror');
+                    return false;
+                }
 
-					// Prune items that you can't change.
-					unset($pks[$i]);
+                // If the table is checked out by another user, drop it and report to the user trying to change its state.
+                if (property_exists($table, 'checked_out') && $table->checked_out && ($table->checked_out != $user->id)) {
+                    \JLog::add(\JText::_('JLIB_APPLICATION_ERROR_CHECKIN_USER_MISMATCH'), \JLog::WARNING, 'jerror');
 
-					return false;
-				}
-			}
+                    // Prune items that you can't change.
+                    unset($pks[$i]);
+
+                    return false;
+                }
+
+                // Get the task - if it is "trash" then trigger event_before_delete
+                $task = \JFactory::getApplication()->input->getCmd('task');
+
+                if ($task === 'trash')
+                {
+                    $context = $this->option . '.' . $this->name;
+
+                    // Trigger the before delete event so it checks if category is empty.
+                    $resultItem = \JFactory::getApplication()->triggerEvent($this->event_before_delete, array($context, $table));
+
+                    // If the previously checked category has items associated with it, it cannot be moved to trash.
+                    if (in_array(false, $resultItem, true))
+                    {
+                        // Prune items that you can't change.
+                        unset($pks[$i]);
+                        return false;
+
+                    }
+
+                }
+            }
 		}
 
-		// Attempt to change the state of the records.
+
+        // Attempt to change the state of the records.
 		if (!$table->publish($pks, $value, $user->get('id')))
 		{
 			$this->setError($table->getError());

plugins/content/joomla/joomla.php

@@ -240,8 +240,11 @@ private function _canDeleteStates($pk)
 		// Now check to see if this is a known core extension
 		if (isset($tableInfo[$extension]))
 		{
-			// See if this category has any content items
-			$count = $this->_countItemsFromState($extension, $pk, $tableInfo[$extension]);
+            // Get table name for known core extensions
+            $table = $tableInfo[$extension]['table_name'];
+
+            // See if this category has any content items
+            $count = $this->_countItemsFromState($extension, $pk, $table);
 
 			// Return false if db error
 			if ($count === false)
@@ -366,6 +369,7 @@ private function _countItemsInChildren($table, $catid, $data)
 	 *
 	 * @since  __DEPLOY_VERSION__
 	 */
+
 	private function _countItemsFromState($extension, $state_id, $table)
 	{
 		$query = $this->db->getQuery(true);