re-implemented tracklist to term_reference_tree

web/modules/dev/term_reference_tree/src/Element/CheckboxTree.php

@@ -78,7 +78,43 @@ class CheckboxTree extends FormElement {
     $tree = new \stdClass();
     $tree->children = $terms;
     unset($element['#needs_validation']);
-    $element[] = _term_reference_tree_build_level($element, $tree, $form_state, $value, $element['#max_choices'], [], 1);
+    $element['checkbox_tree'] = _term_reference_tree_build_level($element, $tree, $form_state, $value, $element['#max_choices'], [], 1);
+
+    // track list
+    if ($element['#track_list']) {
+      if($form_state->getTriggeringElement()){
+        // we are on ajax
+        // $value is not updated on ajax callback
+        // we need an other way to get wich options are checked
+        // and give an accurate track list
+
+        $parent = $element['#parents'][0]; // get the element's parent field
+        $input = $form_state->getUserInput(); // get all inputs from form state
+        $checkbox_tree_input = $input[$parent]['checkbox_tree']; // get the chekbox_tree input
+        $selected = _term_reference_tree_get_flatten_selected_values($checkbox_tree_input); // get selected flattenized
+
+        $track_list_input = $input[$parent]['track_list']; // get the current track_list input with correct order
+        $old_list = array_keys($track_list_input); // flattenize
+
+        // remove all chebox_tree input unselected from the list
+        $list = [];
+        foreach ($old_list as $id) {
+          if(in_array($id, $selected)){
+            $list[] = $id;
+          }
+        }
+        // append newly selected
+        $diff = array_diff($selected, $list);
+        foreach ($diff as $id) {
+          $list[] = $id;
+        }
+      }else{
+        // if not ajax just get the default value
+        $list = $value;
+      }
+      // build the track_list form element
+      $element['track_list'] = _term_reference_tree_build_track_list_order($list, $element['#options']);
+    }
     return $element;
   }
 

web/modules/dev/term_reference_tree/src/Plugin/Field/FieldWidget/TermReferenceTree.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\term_reference_tree\Plugin\Field\FieldWidget;
 
+use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Field\FieldItemListInterface;
 use Drupal\Core\Field\WidgetBase;
 use Drupal\Core\Form\FormStateInterface;
@@ -37,6 +38,7 @@ class TermReferenceTree extends WidgetBase {
         'leaves_only' => FALSE,
         'select_parents' => FALSE,
         'cascading_selection' => self::CASCADING_SELECTION_NONE,
+        'track_list' => FALSE,
         'max_depth' => 0,
       ] + parent::defaultSettings();
   }
@@ -94,6 +96,15 @@ class TermReferenceTree extends WidgetBase {
       $form['cascading_selection']['#description'] .= ' <em>' . $this->t("This option is only valid if an unlimited number of values can be selected.") . '</em>';
     }
 
+    $form['track_list'] = [
+      '#type' => 'checkbox',
+      '#title' => $this->t('Track list'),
+      '#description' => $this->t('Track what the user has chosen in a list below the tree.
+      Useful when the tree is large, with many levels.'),
+      '#default_value' => $this->getSetting('track_list'),
+      '#return_value' => 1,
+    ];
+
     $form['max_depth'] = [
       '#type' => 'number',
       '#title' => $this->t('Maximum Depth'),
@@ -134,6 +145,10 @@ class TermReferenceTree extends WidgetBase {
       $summary[] = sprintf('%s (%s)', $this->t('Cascading selection'), $this->t('Only deselect'));
     }
 
+    if ($this->getSetting('track_list')) {
+      $summary[] = $this->t('Track list');
+    }
+
     if ($this->getSetting('max_depth')) {
       $summary[] = $this->formatPlural($this->getSetting('max_depth'), 'Maximum Depth: @count level', 'Maximum Depth: @count levels');
     }
@@ -156,6 +171,7 @@ class TermReferenceTree extends WidgetBase {
     $element['#leaves_only'] = $this->getSetting('leaves_only');
     $element['#select_parents'] = $this->getSetting('select_parents');
     $element['#cascading_selection'] = $this->getSetting('cascading_selection');
+    $element['#track_list'] = $this->getSetting('track_list');
     $element['#value_key'] = 'target_id';
     $element['#max_depth'] = $this->getSetting('max_depth');
     $element['#start_minimized'] = $this->getSetting('start_minimized');
@@ -189,6 +205,19 @@ class TermReferenceTree extends WidgetBase {
           array_push($value, [$element['#value_key'] => $child['#value']]);
         }
       }
+      // if track_list enabled, reorder the value array regarding the tablegrag input
+      if (!empty($value) && $element['#track_list']) {
+        $input = &$form_state->getUserInput();
+        $nested_input = NestedArray::getValue($form_state->getValues(), $element['#parents']);
+        if (is_array($nested_input['track_list'])) {
+          $track_list = array_keys($nested_input['track_list']);
+          $sorted_value = [];
+          foreach ($track_list as $id) {
+            $sorted_value[] = $value[array_search($id, array_column($value, 'target_id'))];
+          }
+          $value = $sorted_value;
+        }
+      }
     }
     else {
       // If it's a tree of radio buttons, they all have the same value,