Fix loop

src/Plugin/Block/ArchiveTreeBlock.php

@@ -25,7 +25,6 @@ class ArchiveTreeBlock extends BlockBase {
 
   public function defaultConfiguration() {
     return [
-      // Todo: query for all content types.
       'expand_years' => FALSE,
       'content_types' => ['article'],
     ] + parent::defaultConfiguration();
@@ -40,11 +39,13 @@ class ArchiveTreeBlock extends BlockBase {
       $options[$type->id()] = $type->label();
     }
     $form['content_types'] = [
-      '#type' => 'checkboxes',
+      '#type' => 'select',
       '#title' => $this->t('Content types to include'),
       '#options' => $options,
       '#default_value' => $this->configuration['content_types'],
       '#description' => $this->t('Select one or more content types to include in the archive tree.'),
+      '#multiple' => TRUE,
+      '#size' => min(8, count($options)),
       '#required' => TRUE,
     ];
     $form['expand_years'] = [
@@ -90,15 +91,15 @@ class ArchiveTreeBlock extends BlockBase {
         $tree[$year] = ['count' => 0, 'months' => []];
       }
       if (!isset($tree[$year]['months'][$month])) {
-        $tree[$year]['months'][$month] = 0;
+        $tree[$year]['months'][$month] = ['count' => 0];
       }
       $tree[$year]['count']++;
-      $tree[$year]['months'][$month]++;
+      $tree[$year]['months'][$month]['count']++;
     }
 
     krsort($tree); // Descending years
-    foreach ($tree as &$data) {
-      krsort($data['months']); // Descending months
+    foreach ($tree as $year => $data) {
+      krsort($tree[$year]['months']); // Descending months
     }
 
     $output = '';
@@ -109,12 +110,14 @@ class ArchiveTreeBlock extends BlockBase {
       $output .= '<details' . $open . '><summary class="archive-tree-year">';
       $output .= '<a href="' . $year_url . '">' . $year . '</a> (' . $data['count'] . ')';
       $output .= '</summary>';
-      foreach ($data['months'] as $month => $count) {
+      if (!empty($data['months'])) {
+        foreach ($data['months'] as $month => $month_data) {
           $month_url = '/archive-tree/' . $year . '/' . $month;
           $output .= '<div class="archive-tree-month">';
-        $output .= '<a href="' . $month_url . '">' . $month . '</a> (' . $count . ')';
+          $output .= '<a href="' . $month_url . '">' . $month . '</a> (' . $month_data['count'] . ')';
           $output .= '</div>';
         }
+      }
       $output .= '</details>';
     }