fix(dropdownfields): handle empty value for entities dropdown

Signed-off-by: Thierry Bugier <[email protected]>

Author: btry

ajax/dropdown_values.php

@@ -37,20 +37,28 @@
     || $_REQUEST['dropdown_itemtype'] == '0'
     || !class_exists($_REQUEST['dropdown_itemtype'])) {
    Dropdown::showFromArray(
-      'dropdown_default_value', 
+      'dropdown_default_value',
       [], [
          'display_emptychoice'   => true
       ]
    );
 } else {
+   $itemtype = $_REQUEST['dropdown_itemtype'];
    $question = new PluginFormcreatorQuestion();
    $question->getFromDB((int) $_REQUEST['id']);
-   $defaultValue = isset($question->fields['default_values']) 
+   $defaultValue = isset($question->fields['default_values'])
                    ? $question->fields['default_values']
                    : 0;
-   Dropdown::show($_REQUEST['dropdown_itemtype'], [
+
+   $options = [
       'name'  => 'dropdown_default_value',
       'rand'  => mt_rand(),
       'value' => $defaultValue,
-   ]);
+   ];
+   if ($itemtype == Entity::class) {
+      $options['toadd'] = [
+         -1 => Dropdown::EMPTY_VALUE,
+      ];
+   }
+   Dropdown::show($itemtype, $options);
 }

inc/fields/dropdownfield.class.php

@@ -253,7 +253,16 @@ public function displayField($canEdit = true) {
 
             $dparams['condition'] = $dparams_cond_crit;
 
-            $dparams['display_emptychoice'] = ($this->question->fields['show_empty'] !== '0');
+            $dparams['display_emptychoice'] = false;
+            if ($itemtype != Entity::class) {
+               $dparams['display_emptychoice'] = ($this->question->fields['show_empty'] !== '0');
+            } else {
+               if ($this->question->fields['show_empty'] !== '0') {
+                  $dparams['toadd'] = [
+                     -1 => Dropdown::EMPTY_VALUE,
+                  ];
+               }
+            }
 
             $emptyItem = new $itemtype();
             $emptyItem->getEmpty();